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Effects/NNPS of/IN Habit/NNP and/CC of/IN the/DT Use/VB or/CC Disuse/NNP of/IN Parts/NNS ;/: Correlated/VBN Variation/NNP ;/: Inheritance/NN Changed/VBN habits/NNS produce/VB an/DT inherited/VBN effect/NN ,/, as/IN in/IN the/DT period/NN of/IN the/DT flowering/NN of/IN plants/NNS when/WRB transported/VBN from/IN one/CD climate/NN to/TO another/DT ./. With/IN animals/NNS the/DT increased/VBN use/NN or/CC disuse/NN of/IN parts/NNS has/VBZ had/VBD a/DT more/JJR marked/VBN influence/NN ;/: thus/RB I/PRP find/VB in/IN the/DT domestic/JJ duck/NN that/IN the/DT bones/NNS of/IN the/DT wing/NN weigh/VB less/JJR and/CC the/DT bones/NNS of/IN the/DT leg/NN more/JJR ,/, in/IN proportion/NN to/TO the/DT whole/JJ skeleton/NN ,/, than/IN do/VBP the/DT same/JJ bones/NNS in/IN the/DT wild/JJ duck/NN ;/: and/CC this/DT change/NN may/MD be/VB safely/RB attributed/VBD to/TO the/DT domestic/JJ duck/NN flying/VBG much/JJ less/JJR ,/, and/CC walking/VBG more/JJR ,/, than/IN its/PRP$ wild/JJ parents/NNS ./. The/DT great/JJ and/CC inherited/VBN development/NN of/IN the/DT udders/NNS in/IN cows/NNS and/CC goats/NNS in/IN countries/NNS where/WRB they/PRP are/VBP habitually/RB milked/VBD ,/, in/IN comparison/NN with/IN these/DT organs/NNS in/IN other/JJ countries/NNS ,/, is/VBZ probably/RB another/DT instance/NN of/IN the/DT effects/NNS of/IN use/NN ./. Not/RB one/CD of/IN our/PRP$ domestic/JJ animals/NNS can/MD be/VB named/VBN which/WDT has/VBZ not/RB in/IN some/DT country/NN drooping/VBG ears/NNS ;/: and/CC the/DT view/NN which/WDT has/VBZ been/VBN suggested/VBD that/IN the/DT drooping/VBG is/VBZ due/JJ to/TO disuse/NN of/IN the/DT muscles/NNS of/IN the/DT ear/NN ,/, from/IN the/DT animals/NNS being/VBG seldom/RB much/JJ alarmed/VBN ,/, seems/VBZ probable/JJ ./. Many/JJ laws/NNS regulate/VB variation/NN ,/, some/DT few/JJ of/IN which/WDT can/MD be/VB dimly/RB seen/VBN ,/, and/CC will/MD hereafter/RB be/VB briefly/NN discussed/VBN ./. I/PRP will/MD here/RB only/RB allude/NN to/TO what/WP may/MD be/VB called/VBN correlated/JJ variation/NN ./. Important/JJ changes/NNS in/IN the/DT embryo/NN or/CC larva/NN will/MD probably/RB entail/VB changes/NNS in/IN the/DT mature/JJ animal/NN ./. In/IN monstrosities/NNS ,/, the/DT correlations/NNS between/IN quite/RB distinct/JJ parts/NNS are/VBP very/RB curious/JJ ;/: and/CC many/JJ instances/NNS are/VBP given/VBN in/IN Isidore/NNP Geoffroy/NNP St/NNP Hilaire's/NNP great/JJ work/NN on/IN this/DT subject/NN ./. Breeders/NNP believe/VBP that/IN long/JJ limbs/NNS are/VBP almost/RB always/RB accompanied/VBN by/IN an/DT elongated/VBN head/NN ./. Some/DT instances/NNS of/IN correlation/NN are/VBP quite/RB whimsical/JJ :/: thus/RB cats/NNS which/WDT are/VBP entirely/RB white/JJ and/CC have/VBP blue/JJ eyes/NNS are/VBP generally/RB deaf/JJ ;/: but/CC it/PRP has/VBZ been/VBN lately/RB stated/VBN by/IN Mr/NNP ./. Tait/NNP that/IN this/DT is/VBZ confined/VBN to/TO the/DT males/NNS ./. Colour/NNP and/CC constitutional/JJ peculiarities/NNS go/VB together/RB ,/, of/IN which/WDT many/JJ remarkable/JJ cases/NNS could/MD be/VB given/VBN amongst/IN animals/NNS and/CC plants/NNS ./. 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Virginia/NNP squatters/NNS )/SYM added/VBD ,/, "/" we/PRP select/VB the/DT black/JJ members/NNS of/IN a/DT litter/NN for/IN raising/VBG ,/, as/IN they/PRP alone/RB have/VBP a/DT good/JJ chance/NN of/IN living/VBG ./. "/" Hairless/NNP dogs/NNS have/VBP imperfect/JJ teeth/NNS ;/: long/JJ haired/VBN and/CC coarse/JJ haired/VBN animals/NNS are/VBP apt/JJ to/TO have/VB ,/, as/IN is/VBZ asserted/VBN ,/, long/JJ or/CC many/JJ horns/NNS ;/: pigeons/NNS with/IN feathered/JJ feet/NNS have/VBP skin/NN between/IN their/PRP$ outer/JJ toes/NNS ;/: pigeons/NNS with/IN short/JJ beaks/NNS have/VBP small/JJ feet/NNS ,/, and/CC those/DT with/IN long/JJ beaks/NNS large/JJ feet/NNS ./. Hence/RB if/IN man/NN goes/VBZ on/IN selecting/VBG ,/, and/CC thus/RB augmenting/VBG ,/, any/DT peculiarity/NN ,/, he/PRP will/MD almost/RB certainly/RB modify/VB unintentionally/RB other/JJ parts/NNS of/IN the/DT structure/NN ,/, owing/JJ to/TO the/DT mysterious/JJ laws/NNS of/IN correlation/NN ./. 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But/CC the/DT number/NN and/CC diversity/NN of/IN inheritable/JJ deviations/NNS of/IN structure/NN ,/, both/DT those/DT of/IN slight/JJ and/CC those/DT of/IN considerable/JJ physiological/JJ importance/NN ,/, are/VBP endless/JJ ./. Dr/NNP ./. Prosper/NNP Lucas's/NNP treatise/NN ,/, in/IN two/CD large/JJ volumes/NNS ,/, is/VBZ the/DT fullest/JJS and/CC the/DT best/JJS on/IN this/DT subject/NN ./. No/DT breeder/NN doubts/NNS how/WRB strong/JJ is/VBZ the/DT tendency/NN to/TO inheritance/NN ;/: that/IN like/IN produces/VBZ like/IN is/VBZ his/PRP$ fundamental/JJ belief/NN :/: doubts/NNS have/VBP been/VBN thrown/VBN on/IN this/DT principle/NN only/RB by/IN theoretical/JJ writers/NNS ./. 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Every/DT one/CD must/MD have/VB heard/VBN of/IN cases/NNS of/IN albinism/NN ,/, prickly/JJ skin/NN ,/, hairy/JJ bodies/NNS ,/, &c/NN ./. ,/, appearing/VBG in/IN several/JJ members/NNS of/IN the/DT same/JJ family/NN ./. If/IN strange/JJ and/CC rare/JJ deviations/NNS of/IN structure/NN are/VBP really/RB inherited/VBN ,/, less/JJR strange/JJ and/CC commoner/JJR deviations/NNS may/MD be/VB freely/RB admitted/VBD to/TO be/VB inheritable/JJ ./. Perhaps/RB the/DT correct/JJ way/NN of/IN viewing/VBG the/DT whole/JJ subject/NN would/MD be/VB ,/, to/TO look/VB at/IN the/DT inheritance/NN of/IN every/DT character/NN whatever/WDT as/IN the/DT rule/NN ,/, and/CC non/FW inheritance/NN as/IN the/DT anomaly/NN ?/. The/DT laws/NNS governing/VBG inheritance/NN are/VBP for/IN the/DT most/RBS part/NN unknown/JJ ./. No/DT one/CD can/MD say/VB why/WRB the/DT same/JJ peculiarity/NN in/IN different/JJ individuals/NNS of/IN the/DT same/JJ species/NN ,/, or/CC in/IN different/JJ species/NN ,/, is/VBZ sometimes/RB inherited/VBN and/CC sometimes/RB not/RB so/RB ;/: why/WRB the/DT child/NN often/RB reverts/VBZ in/IN certain/JJ characters/NNS to/TO its/PRP$ grandfather/NN or/CC grandmother/NN or/CC more/JJR remote/JJ ancestor/NN ;/: why/WRB a/DT peculiarity/NN is/VBZ often/RB transmitted/VBN from/IN one/CD sex/NN to/TO both/DT sexes/NNS ,/, or/CC to/TO one/CD sex/NN alone/RB ,/, more/JJR commonly/RB but/CC not/RB exclusively/RB to/TO the/DT like/IN sex/NN ./. It/PRP is/VBZ a/DT fact/NN of/IN some/DT importance/NN to/TO us/PRP ,/, that/IN peculiarities/NNS appearing/VBG in/IN the/DT males/NNS of/IN our/PRP$ domestic/JJ breeds/NNS are/VBP often/RB transmitted/VBN ,/, either/DT exclusively/RB or/CC in/IN a/DT much/JJ greater/JJR degree/NN ,/, to/TO the/DT males/NNS alone/RB ./. 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I/PRP cannot/MD doubt/NN that/IN if/IN other/JJ animals/NNS and/CC plants/NNS ,/, equal/JJ in/IN number/NN to/TO our/PRP$ domesticated/VBN productions/NNS ,/, and/CC belonging/VBG to/TO equally/RB diverse/JJ classes/NNS and/CC countries/NNS ,/, were/VBD taken/VBN from/IN a/DT state/NN of/IN nature/NN ,/, and/CC could/MD be/VB made/VBN to/TO breed/NN for/IN an/DT equal/JJ number/NN of/IN generations/NNS under/IN domestication/NN ,/, they/PRP would/MD on/IN an/DT average/JJ vary/VBP as/IN largely/RB as/IN the/DT parent/NN species/NN of/IN our/PRP$ existing/VBG domesticated/VBN productions/NNS have/VBP varied/VBN ./. In/IN the/DT case/NN of/IN most/RBS of/IN our/PRP$ anciently/RB domesticated/VBN animals/NNS and/CC plants/NNS ,/, it/PRP is/VBZ not/RB possible/JJ to/TO come/VB to/TO any/DT definite/JJ conclusion/NN ,/, whether/IN they/PRP are/VBP descended/VBD from/IN one/CD or/CC several/JJ wild/JJ species/NN ./. 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Since/IN the/DT discovery/NN of/IN flint/NN tools/NNS in/IN the/DT superficial/JJ formations/NNS of/IN many/JJ parts/NNS of/IN the/DT world/NN ,/, all/DT geologists/NNS believe/VBP that/IN barbarian/NN man/NN existed/VBD at/IN an/DT enormously/RB remote/JJ period/NN ;/: and/CC we/PRP know/VB that/IN at/IN the/DT present/JJ day/NN there/EX is/VBZ hardly/RB a/DT tribe/NN so/RB barbarous/JJ ,/, as/IN not/RB to/TO have/VB domesticated/VBN at/IN least/JJS the/DT dog/NN ./. The/DT origin/NN of/IN most/RBS of/IN our/PRP$ domestic/JJ animals/NNS will/MD probably/RB for/IN ever/RB remain/VB vague/JJ ./. 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Many/JJ cases/NNS are/VBP on/IN record/NN ,/, showing/VBG that/IN a/DT race/NN may/MD be/VB modified/VBN by/IN occasional/JJ crosses/VBZ ,/, if/IN aided/VBN by/IN the/DT careful/JJ selection/NN of/IN the/DT individuals/NNS which/WDT present/JJ the/DT desired/VBN character/NN ;/: but/CC to/TO obtain/VB a/DT race/NN intermediate/JJ between/IN two/CD quite/RB distinct/JJ races/NNS ,/, would/MD be/VB very/RB difficult/JJ ./. Sir/NNP J/NNP ./. Sebright/NNP expressly/RB experimented/VBD with/IN this/DT object/NN and/CC failed/VBD ./. The/DT offspring/NN from/IN the/DT first/JJ cross/VB between/IN two/CD pure/JJ breeds/NNS is/VBZ tolerably/RB and/CC sometimes/RB (/( as/IN I/PRP have/VBP found/VBD with/IN pigeons/NNS )/SYM quite/RB uniform/NN in/IN character/NN ,/, and/CC everything/NN seems/VBZ simple/JJ enough/RB ;/: but/CC when/WRB these/DT mongrels/NNS are/VBP crossed/VBD one/CD with/IN another/DT for/IN several/JJ generations/NNS ,/, hardly/RB two/CD of/IN them/PRP are/VBP alike/RB and/CC then/RB the/DT difficulty/NN of/IN the/DT task/NN becomes/VBZ manifest/JJ ./. Breeds/NNP of/IN the/DT Domestic/JJ Pigeon/NNP ,/, their/PRP$ Differences/NNS and/CC Origin/NN Believing/VBG that/IN it/PRP is/VBZ always/RB best/JJS to/TO study/NN some/DT special/JJ group/NN ,/, I/PRP have/VBP ,/, after/IN deliberation/NN ,/, taken/VBN up/IN domestic/JJ pigeons/NNS ./. I/PRP have/VBP kept/VBD every/DT breed/NN which/WDT I/PRP could/MD purchase/NN or/CC obtain/VB ,/, and/CC have/VBP been/VBN most/RBS kindly/RB favoured/VBN with/IN skins/NNS from/IN several/JJ quarters/NNS of/IN the/DT world/NN ,/, more/JJR especially/RB by/IN the/DT Hon/NNP ./. W/NNP ./. Elliot/NNP from/IN India/NNP ,/, and/CC by/IN the/DT Hon/NNP ./. C/NN ./. Murray/NNP from/IN Persia/NNP ./. Many/JJ treatises/NNS in/IN different/JJ languages/NNS have/VBP been/VBN published/VBN on/IN pigeons/NNS ,/, and/CC some/DT of/IN them/PRP are/VBP very/RB important/JJ ,/, as/IN being/VBG of/IN considerable/JJ antiquity/NN ./. I/PRP have/VBP associated/VBN with/IN several/JJ eminent/JJ fanciers/NNS ,/, and/CC have/VBP been/VBN permitted/VBN to/TO join/VB two/CD of/IN the/DT London/NNP Pigeon/NNP Clubs/NNPS ./. The/DT diversity/NN of/IN the/DT breeds/NNS is/VBZ something/NN astonishing/JJ ./. Compare/VB the/DT English/NNP carrier/NN and/CC the/DT short/JJ faced/VBN tumbler/NN ,/, and/CC see/VB the/DT wonderful/JJ difference/NN in/IN their/PRP$ beaks/NNS ,/, entailing/VBG corresponding/JJ differences/NNS in/IN their/PRP$ skulls/NNS ./. The/DT carrier/NN ,/, more/JJR especially/RB the/DT male/JJ bird/NN ,/, is/VBZ also/RB remarkable/JJ from/IN the/DT wonderful/JJ development/NN of/IN the/DT carunculated/VBN skin/NN about/IN the/DT head/NN ;/: and/CC this/DT is/VBZ accompanied/VBN by/IN greatly/RB elongated/VBN eyelids/NNS ,/, very/RB large/JJ external/JJ orifices/NNS to/TO the/DT nostrils/NNS ,/, and/CC a/DT wide/JJ gape/NN of/IN mouth/NN ./. The/DT short/JJ faced/VBN tumbler/NN has/VBZ a/DT beak/NN in/IN outline/NN almost/RB like/IN that/IN of/IN a/DT finch/NN ;/: and/CC the/DT common/JJ tumbler/NN has/VBZ the/DT singular/JJ inherited/VBN habit/NN of/IN flying/VBG at/IN a/DT great/JJ height/NN in/IN a/DT compact/JJ flock/NN ,/, and/CC tumbling/VBG in/IN the/DT air/NN head/NN over/IN heels/NNS ./. The/DT runt/NN is/VBZ a/DT bird/NN of/IN great/JJ size/NN ,/, with/IN long/JJ massive/JJ beak/NN and/CC large/JJ feet/NNS ;/: some/DT of/IN the/DT sub/NN breeds/NNS of/IN runts/NNS have/VBP very/RB long/JJ necks/NNS ,/, others/NNS very/RB long/JJ wings/NNS and/CC tails/NNS ,/, others/NNS singularly/RB short/JJ tails/NNS ./. The/DT barb/NN is/VBZ allied/VBN to/TO the/DT carrier/NN ,/, but/CC ,/, instead/RB of/IN a/DT long/JJ beak/NN has/VBZ a/DT very/RB short/JJ and/CC broad/JJ one/CD ./. The/DT pouter/NN has/VBZ a/DT much/JJ elongated/VBN body/NN ,/, wings/NNS ,/, and/CC legs/NNS ;/: and/CC its/PRP$ enormously/RB developed/VBN crop/NN ,/, which/WDT it/PRP glories/NNS in/IN inflating/VBG ,/, may/MD well/RB excite/VB astonishment/NN and/CC even/RB laughter/NN ./. The/DT turbit/NN has/VBZ a/DT short/JJ and/CC conical/JJ beak/NN ,/, with/IN a/DT line/NN of/IN reversed/VBD feathers/NNS down/RB the/DT breast/NN ;/: and/CC it/PRP has/VBZ the/DT habit/NN of/IN continually/RB expanding/VBG slightly/RB ,/, the/DT upper/JJ part/NN of/IN the/DT oesophagus/JJ ./. The/DT Jacobin/NNP has/VBZ the/DT feathers/NNS so/RB much/JJ reversed/VBD along/IN the/DT back/RB of/IN the/DT neck/NN that/IN they/PRP form/NN a/DT hood/NN ;/: and/CC it/PRP has/VBZ ,/, proportionally/RB to/TO its/PRP$ size/NN ,/, elongated/VBN wing/NN and/CC tail/NN feathers/NNS ./. The/DT trumpeter/NN and/CC laugher/NN ,/, as/IN their/PRP$ names/NNS express/VB ,/, utter/JJ a/DT very/RB different/JJ coo/JJ from/IN the/DT other/JJ breeds/NNS ./. The/DT fantail/NN has/VBZ thirty/CD or/CC even/RB forty/CD tailfeathers/NNS ,/, instead/RB of/IN twelve/CD or/CC fourteen/CD the/DT normal/JJ number/NN in/IN all/DT the/DT members/NNS of/IN the/DT great/JJ pigeon/NN family/NN :/: these/DT feathers/NNS are/VBP kept/VBD expanded/VBN ,/, and/CC are/VBP carried/VBD so/RB erect/VB ,/, that/IN in/IN good/JJ birds/NNS the/DT head/NN and/CC tail/NN touch/NN :/: the/DT oil/NN gland/NN is/VBZ quite/RB aborted/JJ ./. Several/JJ other/JJ less/JJR distinct/JJ breeds/NNS might/MD be/VB specified/VBN ./. In/IN the/DT skeletons/NNS of/IN the/DT several/JJ breeds/NNS ,/, the/DT development/NN of/IN the/DT bones/NNS of/IN the/DT face/NN in/IN length/NN and/CC breadth/NN and/CC curvature/NN differs/VBZ enormously/RB ./. The/DT shape/NN ,/, as/IN well/RB as/IN the/DT breadth/NN and/CC length/NN of/IN the/DT ramus/JJ of/IN the/DT lower/JJR jaw/NN ,/, varies/VBZ in/IN a/DT highly/RB remarkable/JJ manner/NN ./. The/DT caudal/JJ and/CC sacral/JJ vertebrae/NNS vary/VBP in/IN number/NN ;/: as/IN does/VBZ the/DT number/NN of/IN the/DT ribs/NNS ,/, together/RB with/IN their/PRP$ relative/JJ breadth/NN and/CC the/DT presence/NN of/IN processes/NNS ./. The/DT size/NN and/CC shape/NN of/IN the/DT apertures/NNS in/IN the/DT sternum/NN are/VBP highly/RB variable/JJ ;/: so/RB is/VBZ the/DT degree/NN of/IN divergence/NN and/CC relative/JJ size/NN of/IN the/DT two/CD arms/NNS of/IN the/DT furcula/NN ./. The/DT proportional/JJ width/NN of/IN the/DT gape/NN of/IN mouth/NN ,/, the/DT proportional/JJ length/NN of/IN the/DT eyelids/NNS ,/, of/IN the/DT orifice/NN of/IN the/DT nostrils/NNS ,/, of/IN the/DT tongue/NN (/( not/RB always/RB in/IN strict/JJ correlation/NN with/IN the/DT length/NN of/IN beak/NN )/SYM ,/, the/DT size/NN of/IN the/DT crop/NN and/CC of/IN the/DT upper/JJ part/NN of/IN the/DT oesophagus/JJ ;/: the/DT development/NN and/CC abortion/NN of/IN the/DT oil/NN gland/NN ;/: the/DT number/NN of/IN the/DT primary/JJ wing/NN and/CC caudal/JJ feathers/NNS ;/: the/DT relative/JJ length/NN of/IN the/DT wing/NN and/CC tail/NN to/TO each/DT other/JJ and/CC to/TO the/DT body/NN ;/: the/DT relative/JJ length/NN of/IN the/DT leg/NN and/CC foot/NN ;/: the/DT number/NN of/IN scutellae/NN on/IN the/DT toes/NNS ,/, the/DT development/NN of/IN skin/NN between/IN the/DT toes/NNS ,/, are/VBP all/DT points/NNS of/IN structure/NN which/WDT are/VBP variable/JJ ./. The/DT period/NN at/IN which/WDT the/DT perfect/JJ plumage/NN is/VBZ acquired/VBN varies/VBZ ,/, as/IN does/VBZ the/DT state/NN of/IN the/DT down/RB with/IN which/WDT the/DT nestling/NN birds/NNS are/VBP clothed/VBN when/WRB hatched/VBN ./. The/DT shape/NN and/CC size/NN of/IN the/DT eggs/NNS vary/VBP ./. The/DT manner/NN of/IN flight/NN ,/, and/CC in/IN some/DT breeds/NNS the/DT voice/NN and/CC disposition/NN ,/, differ/VBP remarkably/RB ./. Lastly/RB ,/, in/IN certain/JJ breeds/NNS ,/, the/DT males/NNS and/CC females/NNS have/VBP come/VB to/TO differ/VB in/IN a/DT slight/JJ degree/NN from/IN each/DT other/JJ ./. Altogether/RB at/IN least/JJS a/DT score/NN of/IN pigeons/NNS might/MD be/VB chosen/VBN ,/, which/WDT ,/, if/IN shown/VBN to/TO an/DT ornithologist/NN ,/, and/CC he/PRP were/VBD told/VBD that/IN they/PRP were/VBD wild/JJ birds/NNS ,/, would/MD certainly/RB be/VB ranked/VBD by/IN him/PRP as/IN well/RB defined/VBN species/NN ./. Moreover/RB ,/, I/PRP do/VBP not/RB believe/VBP that/IN any/DT ornithologist/NN would/MD in/IN this/DT case/NN place/NN the/DT English/NNP carrier/NN ,/, the/DT short/JJ faced/VBN tumbler/NN ,/, the/DT runt/NN ,/, the/DT barb/NN ,/, pouter/NN ,/, and/CC fantail/NN in/IN the/DT same/JJ genus/NN ;/: more/JJR especially/RB as/IN in/IN each/DT of/IN these/DT breeds/NNS several/JJ truly/RB inherited/VBN sub/NN breeds/NNS ,/, or/CC species/NN ,/, as/IN he/PRP would/MD call/VB them/PRP ,/, could/MD be/VB shown/VBN him/PRP ./. Great/NNP as/IN are/VBP the/DT differences/NNS between/IN the/DT breeds/NNS of/IN the/DT pigeon/NN ,/, I/PRP am/VBP fully/RB convinced/VBN that/IN the/DT common/JJ opinion/NN of/IN naturalists/NNS is/VBZ correct/JJ ,/, namely/RB ,/, that/IN all/DT are/VBP descended/VBD from/IN the/DT rock/NN pigeon/NN (/( Columba/NNP livia/NN )/SYM ,/, including/VBG under/IN this/DT term/NN several/JJ geographical/JJ races/NNS or/CC sub/NN species/NN ,/, which/WDT differ/VBP from/IN each/DT other/JJ in/IN the/DT most/RBS trifling/JJ respects/NNS ./. As/IN several/JJ of/IN the/DT reasons/NNS which/WDT have/VBP led/VBN me/PRP to/TO this/DT belief/NN are/VBP in/IN some/DT degree/NN applicable/JJ in/IN other/JJ cases/NNS ,/, I/PRP will/MD here/RB briefly/NN give/VB them/PRP ./. If/IN the/DT several/JJ breeds/NNS are/VBP not/RB varieties/NNS ,/, and/CC have/VBP not/RB proceeded/VBD from/IN the/DT rock/NN pigeon/NN ,/, they/PRP must/MD have/VB descended/VBD from/IN at/IN least/JJS seven/CD or/CC eight/CD aboriginal/JJ stocks/NNS ;/: for/IN it/PRP is/VBZ impossible/JJ to/TO make/VB the/DT present/JJ domestic/JJ breeds/NNS by/IN the/DT crossing/VBG of/IN any/DT lesser/JJR number/NN :/: how/WRB ,/, for/IN instance/NN ,/, could/MD a/DT pouter/NN be/VB produced/VBN by/IN crossing/VBG two/CD breeds/NNS unless/IN one/CD of/IN the/DT parent/NN stocks/NNS possessed/VBD the/DT characteristic/JJ enormous/JJ crop/NN ?/. The/DT supposed/VBN aboriginal/JJ stocks/NNS must/MD all/DT have/VBP been/VBN rock/NN pigeons/NNS ,/, that/IN is/VBZ ,/, they/PRP did/VBD not/RB breed/NN or/CC willingly/RB perch/NN on/IN trees/NNS ./. But/CC besides/IN C/NN ./. livia/NN ,/, with/IN its/PRP$ geographical/JJ sub/NN species/NN ,/, only/RB two/CD or/CC three/CD other/JJ species/NN of/IN rock/NN pigeons/NNS are/VBP known/VBN ;/: and/CC these/DT have/VBP not/RB any/DT of/IN the/DT characters/NNS of/IN the/DT domestic/JJ breeds/NNS ./. Hence/RB the/DT supposed/VBN aboriginal/JJ stocks/NNS must/MD either/DT still/RB exist/VB in/IN the/DT countries/NNS where/WRB they/PRP were/VBD originally/RB domesticated/VBN ,/, and/CC yet/RB be/VB unknown/JJ to/TO ornithologists/NNS ;/: and/CC this/DT ,/, considering/VBG their/PRP$ size/NN ,/, habits/NNS ,/, and/CC remarkable/JJ characters/NNS ,/, seems/VBZ improbable/JJ ;/: or/CC they/PRP must/MD have/VB become/VB extinct/JJ in/IN the/DT wild/JJ state/NN ./. But/CC birds/NNS breeding/VBG on/IN precipices/NNS ,/, and/CC good/JJ fliers/NNS ,/, are/VBP unlikely/JJ to/TO be/VB exterminated/VBN ;/: and/CC the/DT common/JJ rock/NN pigeon/NN ,/, which/WDT has/VBZ the/DT same/JJ habits/NNS with/IN the/DT domestic/JJ breeds/NNS ,/, has/VBZ not/RB been/VBN exterminated/VBN even/RB on/IN several/JJ of/IN the/DT smaller/JJR British/JJ islets/NNS ,/, or/CC on/IN the/DT shores/NNS of/IN the/DT Mediterranean/NNP ./. Hence/RB the/DT supposed/VBN extermination/NN of/IN so/RB many/JJ species/NN having/VBG similar/JJ habits/NNS with/IN the/DT rock/NN pigeon/NN seems/VBZ a/DT very/RB rash/NN assumption/NN ./. Moreover/RB ,/, the/DT several/JJ above/IN named/VBN domesticated/VBN breeds/NNS have/VBP been/VBN transported/VBN to/TO all/DT parts/NNS of/IN the/DT world/NN ,/, and/CC ,/, therefore/RB ,/, some/DT of/IN them/PRP must/MD have/VB been/VBN carried/VBD back/RB again/RB into/IN their/PRP$ native/JJ country/NN ;/: but/CC not/RB one/CD has/VBZ become/VB wild/JJ or/CC feral/JJ ,/, though/IN the/DT dovecot/NN pigeon/NN ,/, which/WDT is/VBZ the/DT rock/NN pigeon/NN in/IN very/RB slightly/RB altered/VBN state/NN ,/, has/VBZ become/VB feral/JJ in/IN several/JJ places/NNS ./. Again/RB ,/, all/DT recent/JJ experience/NN shows/VBZ that/IN it/PRP is/VBZ difficult/JJ to/TO get/VB wild/JJ animals/NNS to/TO breed/NN freely/RB under/IN domestication/NN ,/, yet/RB on/IN the/DT hypothesis/NN of/IN the/DT multiple/JJ origin/NN of/IN our/PRP$ pigeons/NNS ,/, it/PRP must/MD be/VB assumed/VBN that/IN at/IN least/JJS seven/CD or/CC eight/CD species/NN were/VBD so/RB thoroughly/RB domesticated/VBN in/IN ancient/JJ times/NNS by/IN half/NN civilised/JJ man/NN ,/, as/IN to/TO be/VB quite/RB prolific/JJ under/IN confinement/NN ./. An/DT argument/NN of/IN great/JJ weight/NN ,/, and/CC applicable/JJ in/IN several/JJ other/JJ cases/NNS ,/, is/VBZ ,/, that/IN the/DT above/IN specified/VBN breeds/NNS ,/, though/IN agreeing/VBG generally/RB with/IN the/DT wild/JJ rock/NN pigeon/NN in/IN constitution/NN ,/, habits/NNS ,/, voice/NN ,/, colouring/VBG ,/, and/CC in/IN most/RBS parts/NNS of/IN their/PRP$ structure/NN ,/, yet/RB are/VBP certainly/RB highly/RB abnormal/JJ in/IN other/JJ parts/NNS ;/: we/PRP may/MD look/VB in/IN vain/JJ through/IN the/DT whole/JJ great/JJ family/NN of/IN Columbidae/NNP for/IN a/DT beak/NN like/IN that/IN of/IN the/DT English/NNP carrier/NN ,/, or/CC that/IN of/IN the/DT short/JJ faced/VBN tumbler/NN ,/, or/CC barb/NN ;/: for/IN reversed/VBD feathers/NNS like/IN those/DT of/IN the/DT Jacobin/NNP ;/: for/IN a/DT crop/NN like/IN that/IN of/IN the/DT pouter/NN ;/: for/IN tail/NN feathers/NNS like/IN those/DT of/IN the/DT fantail/NN ./. Hence/RB it/PRP must/MD be/VB assumed/VBN not/RB only/RB that/IN half/NN civilised/JJ man/NN succeeded/VBN in/IN thoroughly/RB domesticating/VBG several/JJ species/NN ,/, but/CC that/IN he/PRP intentionally/RB or/CC by/IN chance/NN picked/VBD out/IN extraordinarily/RB abnormal/JJ species/NN ;/: and/CC further/JJR ,/, that/IN these/DT very/RB species/NN have/VBP since/IN all/DT become/VB extinct/JJ or/CC unknown/JJ ./. So/RB many/JJ strange/JJ contingencies/NNS are/VBP improbable/JJ in/IN the/DT highest/JJS degree/NN ./. Some/DT facts/NNS in/IN regard/NN to/TO the/DT colouring/VBG of/IN pigeons/NNS well/RB deserve/VBP consideration/NN ./. The/DT rock/NN pigeon/NN is/VBZ of/IN a/DT slaty/JJ blue/JJ ,/, with/IN white/JJ loins/NNS ;/: but/CC the/DT Indian/NNP sub/NN species/NN ,/, C/NN ./. intermedia/NN of/IN Strickland/NNP ,/, has/VBZ this/DT part/NN bluish/JJ ./. The/DT tail/NN has/VBZ a/DT terminal/NN dark/JJ bar/NN ,/, with/IN the/DT outer/JJ feathers/NNS externally/RB edged/VBD at/IN the/DT base/NN with/IN white/JJ ./. The/DT wings/NNS have/VBP two/CD black/JJ bars/NNS ./. Some/DT semi/NN domestic/JJ breeds/NNS ,/, and/CC some/DT truly/RB wild/JJ breeds/NNS ,/, have/VBP ,/, besides/IN the/DT two/CD black/JJ bars/NNS ,/, the/DT wings/NNS chequered/VBN with/IN black/JJ ./. These/DT several/JJ marks/NNS do/VBP not/RB occur/VB together/RB in/IN any/DT other/JJ species/NN of/IN the/DT whole/JJ family/NN ./. Now/RB ,/, in/IN every/DT one/CD of/IN the/DT domestic/JJ breeds/NNS ,/, taking/VBG thoroughly/RB well/RB bred/VBN birds/NNS ,/, all/DT the/DT above/IN marks/NNS ,/, even/RB to/TO the/DT white/JJ edging/VBG of/IN the/DT outer/JJ tail/NN feathers/NNS ,/, sometimes/RB concur/VBP perfectly/RB developed/VBN ./. Moreover/RB ,/, when/WRB birds/NNS belonging/VBG to/TO two/CD or/CC more/JJR distinct/JJ breeds/NNS are/VBP crossed/VBD ,/, none/NN of/IN which/WDT are/VBP blue/JJ or/CC have/VBP any/DT of/IN the/DT above/IN specified/VBN marks/NNS ,/, the/DT mongrel/NN offspring/NN are/VBP very/RB apt/JJ suddenly/RB to/TO acquire/VB these/DT characters/NNS ./. To/TO give/VB one/CD instance/NN out/IN of/IN several/JJ which/WDT I/PRP have/VBP observed/VBN :/: I/PRP crossed/VBD some/DT white/JJ fantails/NNS ,/, which/WDT breed/NN very/RB true/JJ ,/, with/IN some/DT black/JJ barbs/NNS and/CC it/PRP so/RB happens/VBZ that/IN blue/JJ varieties/NNS of/IN barbs/NNS are/VBP so/RB rare/JJ that/IN I/PRP never/RB heard/VBN of/IN an/DT instance/NN in/IN England/NNP ;/: and/CC the/DT mongrels/NNS were/VBD black/JJ ,/, brown/JJ ,/, and/CC mottled/VBN ./. I/PRP also/RB crossed/VBD a/DT barb/NN with/IN a/DT spot/NN ,/, which/WDT is/VBZ a/DT white/JJ bird/NN with/IN a/DT red/JJ tail/NN and/CC red/JJ spot/NN on/IN the/DT forehead/NN ,/, and/CC which/WDT notoriously/RB breeds/NNS very/RB true/JJ ;/: the/DT mongrels/NNS were/VBD dusky/JJ and/CC mottled/VBN ./. I/PRP then/RB crossed/VBD one/CD of/IN the/DT mongrel/NN barb/NN fantails/NNS with/IN a/DT mongrel/NN barb/NN spot/NN ,/, and/CC they/PRP produced/VBN a/DT bird/NN of/IN as/IN beautiful/JJ a/DT blue/JJ colour/NN ,/, with/IN the/DT white/JJ loins/NNS ,/, double/JJ black/JJ wing/NN bar/NN ,/, and/CC barred/VBN and/CC white/JJ edged/VBD tail/NN feathers/NNS ,/, as/IN any/DT wild/JJ rock/NN pigeon!/NN We/PRP can/MD understand/VB these/DT facts/NNS ,/, on/IN the/DT well/RB known/VBN principle/NN of/IN reversion/NN to/TO ancestral/JJ characters/NNS ,/, if/IN all/DT the/DT domestic/JJ breeds/NNS are/VBP descended/VBD from/IN the/DT rock/NN pigeon/NN ./. But/CC if/IN we/PRP deny/VB this/DT ,/, we/PRP must/MD make/VB one/CD of/IN the/DT two/CD following/VBG highly/RB improbable/JJ suppositions/NNS ./. Either/CC ,/, first/JJ ,/, that/IN all/DT the/DT several/JJ imagined/VBN aboriginal/JJ stocks/NNS were/VBD coloured/JJ and/CC marked/VBN like/IN the/DT rock/NN pigeon/NN ,/, although/IN no/DT other/JJ existing/VBG species/NN is/VBZ thus/RB coloured/JJ and/CC marked/VBN ,/, so/RB that/IN in/IN each/DT separate/JJ breed/NN there/EX might/MD be/VB a/DT tendency/NN to/TO revert/VB to/TO the/DT very/RB same/JJ colours/NNS and/CC markings/NNS ./. Or/CC ,/, secondly/RB ,/, that/IN each/DT breed/NN ,/, even/RB the/DT purest/JJS ,/, has/VBZ within/IN a/DT dozen/NN ,/, or/CC at/IN most/RBS within/IN a/DT score/NN ,/, of/IN generations/NNS ,/, been/VBN crossed/VBD by/IN the/DT rock/NN pigeon/NN :/: I/PRP say/VBP within/IN dozen/NN or/CC twenty/CD generations/NNS ,/, for/IN no/DT instance/NN is/VBZ known/VBN of/IN crossed/VBD descendants/NNS reverting/VBG to/TO an/DT ancestor/NN of/IN foreign/JJ blood/NN ,/, removed/VBN by/IN a/DT greater/JJR number/NN of/IN generations/NNS ./. In/IN a/DT breed/NN which/WDT has/VBZ been/VBN crossed/VBD only/RB once/RB ,/, the/DT tendency/NN to/TO revert/VB to/TO any/DT character/NN derived/VBN from/IN such/JJ a/DT cross/VB will/MD naturally/RB become/VB less/JJR and/CC less/JJR ,/, as/IN in/IN each/DT succeeding/VBG generation/NN there/EX will/MD be/VB less/JJR of/IN the/DT foreign/JJ blood/NN ;/: but/CC when/WRB there/EX has/VBZ been/VBN no/DT cross/VB ,/, and/CC there/EX is/VBZ a/DT tendency/NN in/IN the/DT breed/NN to/TO revert/VB to/TO a/DT character/NN which/WDT was/VBD lost/VBD during/IN some/DT former/JJ generation/NN ,/, this/DT tendency/NN ,/, for/IN all/DT that/IN we/PRP can/MD see/VB to/TO the/DT contrary/JJ ,/, may/MD be/VB transmitted/VBN undiminished/JJ for/IN an/DT indefinite/JJ number/NN of/IN generations/NNS ./. These/DT two/CD distinct/JJ cases/NNS of/IN reversion/NN are/VBP often/RB confounded/VBD together/RB by/IN those/DT who/WP have/VBP written/VBN on/IN inheritance/NN ./. Lastly/RB ,/, the/DT hybrids/NNS or/CC mongrels/NNS from/IN between/IN all/DT the/DT breeds/NNS of/IN the/DT pigeon/NN are/VBP perfectly/RB fertile/JJ ,/, as/IN I/PRP can/MD state/NN from/IN my/PRP$ own/JJ observations/NNS ,/, purposely/RB made/VBN ,/, on/IN the/DT most/RBS distinct/JJ breeds/NNS ./. Now/RB ,/, hardly/RB any/DT cases/NNS have/VBP been/VBN ascertained/VBN with/IN certainty/NN of/IN hybrids/NNS from/IN two/CD quite/RB distinct/JJ species/NN of/IN animals/NNS being/VBG perfectly/RB fertile/JJ ./. Some/DT authors/NNS believe/VBP that/IN long/JJ continued/VBD domestication/NN eliminates/VBZ this/DT strong/JJ tendency/NN to/TO sterility/NN in/IN species/NN ./. From/IN the/DT history/NN of/IN the/DT dog/NN ,/, and/CC of/IN some/DT other/JJ domestic/JJ animals/NNS ,/, this/DT conclusion/NN is/VBZ probably/RB quite/RB correct/JJ ,/, if/IN applied/VBN to/TO species/NN closely/RB related/VBN to/TO each/DT other/JJ ./. But/CC to/TO extend/VB it/PRP so/RB far/RB as/IN to/TO suppose/VB that/IN species/NN ,/, aboriginally/RB as/IN distinct/JJ as/IN carriers/NNS ,/, tumblers/NNS ,/, pouters/NNS ,/, and/CC fantails/NNS now/RB are/VBP ,/, should/MD yield/VB offspring/NN perfectly/RB fertile/JJ inter/FW se/FW ,/, would/MD be/VB rash/NN in/IN the/DT extreme/JJ ./. From/IN these/DT several/JJ reasons/NNS ,/, namely/RB ,/, the/DT improbability/NN of/IN man/NN having/VBG formerly/RB made/VBN seven/CD or/CC eight/CD supposed/VBN species/NN of/IN pigeons/NNS to/TO breed/NN freely/RB under/IN domestication/NN ;/: these/DT supposed/VBN species/NN being/VBG quite/RB unknown/JJ in/IN a/DT wild/JJ state/NN ,/, and/CC their/PRP$ not/RB having/VBG become/VB anywhere/RB feral/JJ ;/: these/DT species/NN presenting/VBG certain/JJ very/RB abnormal/JJ characters/NNS ,/, as/IN compared/VBN with/IN all/DT other/JJ Columbidae/NNP ,/, though/IN so/RB like/IN the/DT rock/NN pigeon/NN in/IN most/RBS respects/NNS ;/: the/DT occasional/JJ reappearance/NN of/IN the/DT blue/JJ colour/NN and/CC various/JJ black/JJ marks/NNS in/IN all/DT the/DT breeds/NNS ,/, both/DT when/WRB kept/VBD pure/JJ and/CC when/WRB crossed/VBD ;/: and/CC lastly/RB ,/, the/DT mongrel/NN offspring/NN being/VBG perfectly/RB fertile/JJ ;/: from/IN these/DT several/JJ reasons/NNS taken/VBN together/RB ,/, we/PRP may/MD safely/RB conclude/VB that/IN all/DT our/PRP$ domestic/JJ breeds/NNS are/VBP descended/VBD from/IN the/DT rock/NN pigeon/NN or/CC Columba/NNP livia/NN with/IN its/PRP$ geographical/JJ sub/NN species/NN ./. In/IN favour/NN of/IN this/DT view/NN ,/, I/PRP may/MD add/VB ,/, firstly/RB ,/, that/IN the/DT wild/JJ C/NN ./. livia/NN has/VBZ been/VBN found/VBD capable/JJ of/IN domestication/NN in/IN Europe/NNP and/CC in/IN India/NNP ;/: and/CC that/IN it/PRP agrees/VBZ in/IN habits/NNS and/CC in/IN a/DT great/JJ number/NN of/IN points/NNS of/IN structure/NN with/IN all/DT the/DT domestic/JJ breeds/NNS ./. Secondly/RB ,/, that/IN ,/, although/IN an/DT English/NNP carrier/NN or/CC a/DT short/JJ faced/VBN tumbler/NN differs/VBZ immensely/RB in/IN certain/JJ characters/NNS from/IN the/DT rock/NN pigeon/NN ,/, yet/RB that/IN ,/, by/IN comparing/VBG the/DT several/JJ sub/NN breeds/NNS of/IN these/DT two/CD races/NNS ,/, more/JJR especially/RB those/DT brought/VBN from/IN distant/JJ countries/NNS ,/, we/PRP can/MD make/VB ,/, between/IN them/PRP and/CC the/DT rock/NN pigeon/NN ,/, an/DT almost/RB perfect/JJ series/NN ;/: so/RB we/PRP can/MD in/IN some/DT other/JJ cases/NNS ,/, but/CC not/RB with/IN all/DT the/DT breeds/NNS ./. Thirdly/RB ,/, those/DT characters/NNS which/WDT are/VBP mainly/RB distinctive/JJ of/IN each/DT breed/NN are/VBP in/IN each/DT eminently/RB variable/JJ ,/, for/IN instance/NN the/DT wattle/NN and/CC length/NN of/IN beak/NN of/IN the/DT carrier/NN ,/, the/DT shortness/NN of/IN that/IN of/IN the/DT tumbler/NN ,/, and/CC the/DT number/NN of/IN tailfeathers/NNS in/IN the/DT fantail/NN ;/: and/CC the/DT explanation/NN of/IN this/DT fact/NN will/MD be/VB obvious/JJ when/WRB we/PRP treat/VB of/IN Selection/NN ./. Fourthly/RB ,/, pigeons/NNS have/VBP been/VBN watched/VBD and/CC tended/VBD with/IN the/DT utmost/JJ care/NN ,/, and/CC loved/VBD by/IN many/JJ people/NNS ./. They/PRP have/VBP been/VBN domesticated/VBN for/IN thousands/NNS of/IN years/NNS in/IN several/JJ quarters/NNS of/IN the/DT world/NN ;/: the/DT earliest/JJS known/VBN record/NN of/IN pigeons/NNS is/VBZ in/IN the/DT fifth/JJ AEgyptian/NNP dynasty/NN ,/, about/IN 3000/CD B/NNP ./. C/NN ./. ,/, as/IN was/VBD pointed/VBD out/IN to/TO me/PRP by/IN Professor/NNP Lepsius/NNP ;/: but/CC Mr/NNP ./. Birch/NNP informs/VBZ me/PRP that/IN pigeons/NNS are/VBP given/VBN in/IN a/DT bill/NN of/IN fare/NN in/IN the/DT previous/JJ dynasty/NN ./. In/IN the/DT time/NN of/IN the/DT Romans/NNPS ,/, as/IN we/PRP hear/VB from/IN Pliny/NN ,/, immense/JJ prices/NNS were/VBD given/VBN for/IN pigeons/NNS ;/: "/" nay/RB ,/, they/PRP are/VBP come/VB to/TO this/DT pass/VB ,/, that/IN they/PRP can/MD reckon/VB up/IN their/PRP$ pedigree/NN and/CC race/NN ./. "/" Pigeons/NNP were/VBD much/JJ valued/VBN by/IN Akber/NNP Khan/NNP in/IN India/NNP ,/, about/IN the/DT year/NN 1600/CD ;/: never/RB less/JJR than/IN 90/CD ,/, 000/CD pigeons/NNS were/VBD taken/VBN with/IN the/DT court/NN ./. "/" The/DT monarchs/NNS of/IN Iran/NNP and/CC Turan/NNP sent/VBD him/PRP some/DT very/RB rare/JJ birds/NNS "/" ;/: and/CC continues/VBZ the/DT courtly/JJ historian/NN ,/, "/" His/PRP$ Majesty/NNP by/IN crossing/VBG the/DT breeds/NNS ,/, which/WDT method/NN was/VBD never/RB practised/JJ before/IN ,/, has/VBZ improved/VBN them/PRP astonishingly/RB ./. "/" About/IN this/DT same/JJ period/NN the/DT Dutch/JJ were/VBD as/IN eager/JJ about/IN pigeons/NNS as/IN were/VBD the/DT old/JJ Romans/NNPS ./. The/DT paramount/JJ importance/NN of/IN these/DT considerations/NNS in/IN explaining/VBG the/DT immense/JJ amount/NN of/IN variation/NN which/WDT pigeons/NNS have/VBP undergone/VBN ,/, will/MD likewise/RB be/VB obvious/JJ when/WRB we/PRP treat/VB of/IN Selection/NN ./. We/PRP shall/MD then/RB ,/, also/RB ,/, see/VB how/WRB it/PRP is/VBZ that/IN the/DT several/JJ breeds/NNS so/RB often/RB have/VBP a/DT somewhat/RB monstrous/JJ character/NN ./. It/PRP is/VBZ also/RB a/DT most/RBS favourable/JJ circumstance/NN for/IN the/DT production/NN of/IN distinct/JJ breeds/NNS ,/, that/IN male/JJ and/CC female/JJ pigeons/NNS can/MD be/VB easily/RB mated/VBN for/IN life/NN ;/: and/CC thus/RB different/JJ breeds/NNS can/MD be/VB kept/VBD together/RB in/IN the/DT same/JJ aviary/NN ./. I/PRP have/VBP discussed/VBN the/DT probable/JJ origin/NN of/IN domestic/JJ pigeons/NNS at/IN some/DT ,/, yet/RB quite/RB insufficient/JJ ,/, length/NN ;/: because/IN when/WRB I/PRP first/JJ kept/VBD pigeons/NNS and/CC watched/VBD the/DT several/JJ kinds/NNS ,/, well/RB knowing/VBG how/WRB truly/RB they/PRP breed/NN ,/, I/PRP felt/VBD fully/RB as/IN much/JJ difficulty/NN in/IN believing/VBG that/IN since/IN they/PRP had/VBD been/VBN domesticated/VBN they/PRP had/VBD all/DT proceeded/VBD from/IN a/DT common/JJ parent/NN ,/, as/IN any/DT naturalist/NN could/MD in/IN coming/VBG to/TO a/DT similar/JJ conclusion/NN in/IN regard/NN to/TO the/DT many/JJ species/NN of/IN finches/NNS ,/, or/CC other/JJ groups/NNS of/IN birds/NNS ,/, in/IN nature/NN ./. 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I/PRP have/VBP never/RB met/VBD a/DT pigeon/NN ,/, or/CC poultry/NN ,/, or/CC duck/NN ,/, or/CC rabbit/NN fancier/JJR ,/, who/WP was/VBD not/RB fully/RB convinced/VBN that/IN each/DT main/JJ breed/NN was/VBD descended/VBD from/IN a/DT distinct/JJ species/NN ./. Van/NNP Mons/NNP ,/, in/IN his/PRP$ treatise/NN on/IN pears/NNS and/CC apples/NNS ,/, shows/VBZ how/WRB utterly/RB he/PRP disbelieves/VBZ that/IN the/DT several/JJ sorts/NNS ,/, for/IN instance/NN a/DT Ribston/NNP pippin/NN or/CC Codlin/NNP apple/NN ,/, could/MD ever/RB have/VBP proceeded/VBD from/IN the/DT seeds/NNS of/IN the/DT same/JJ tree/NN ./. Innumerable/JJ other/JJ examples/NNS could/MD be/VB given/VBN ./. The/DT explanation/NN ,/, I/PRP think/VBP ,/, is/VBZ simple/JJ :/: from/IN long/JJ continued/VBD study/NN they/PRP are/VBP strongly/RB impressed/VBN with/IN the/DT differences/NNS between/IN the/DT several/JJ races/NNS ;/: and/CC though/IN they/PRP well/RB know/VB that/IN each/DT race/NN varies/VBZ slightly/RB ,/, for/IN they/PRP win/VB their/PRP$ prizes/NNS by/IN selecting/VBG such/JJ slight/JJ differences/NNS ,/, yet/RB they/PRP ignore/VB all/DT general/JJ arguments/NNS ,/, and/CC refuse/VB to/TO sum/NN up/IN in/IN their/PRP$ minds/NNS slight/JJ differences/NNS accumulated/VBN during/IN many/JJ successive/JJ generations/NNS ./. May/NNP not/RB those/DT naturalists/NNS who/WP ,/, knowing/VBG far/RB less/JJR of/IN the/DT laws/NNS of/IN inheritance/NN than/IN does/VBZ the/DT breeder/NN ,/, and/CC knowing/VBG no/DT more/JJR than/IN he/PRP does/VBZ of/IN the/DT intermediate/JJ links/NNS in/IN the/DT long/JJ lines/NNS of/IN descent/NN ,/, yet/RB admit/VB that/IN many/JJ of/IN our/PRP$ domestic/JJ races/NNS are/VBP descended/VBD from/IN the/DT same/JJ parents/NNS may/MD they/PRP not/RB learn/VB a/DT lesson/NN of/IN caution/NN ,/, when/WRB they/PRP deride/VBP the/DT idea/NN of/IN species/NN in/IN a/DT state/NN of/IN nature/NN being/VBG lineal/JJ descendants/NNS of/IN other/JJ species/NN ?/. Principles/NNS of/IN Selection/NN anciently/RB followed/VBD ,/, and/CC their/PRP$ Effects/NNPS Let/VB us/PRP now/RB briefly/NN consider/VB the/DT steps/NNS by/IN which/WDT domestic/JJ races/NNS have/VBP been/VBN produced/VBN ,/, either/DT from/IN one/CD or/CC from/IN several/JJ allied/VBN species/NN ./. Some/DT effect/NN may/MD be/VB attributed/VBD to/TO the/DT direct/JJ and/CC definite/JJ action/NN of/IN the/DT external/JJ conditions/NNS of/IN life/NN ,/, and/CC some/DT to/TO habit/NN ;/: but/CC he/PRP would/MD be/VB a/DT bold/JJ man/NN who/WP would/MD account/NN by/IN such/JJ agencies/NNS for/IN the/DT differences/NNS between/IN a/DT dray/NN and/CC race/NN horse/NN ,/, a/DT greyhound/NN and/CC bloodhound/NN ,/, a/DT carrier/NN and/CC tumbler/NN pigeon/NN ./. One/CD of/IN the/DT most/RBS remarkable/JJ features/NNS in/IN our/PRP$ domesticated/VBN races/NNS is/VBZ that/IN we/PRP see/VB in/IN them/PRP adaptation/NN ,/, not/RB indeed/RB to/TO the/DT animal's/NNS or/CC plant's/NNS own/JJ good/JJ ,/, but/CC to/TO man's/NNS use/NN or/CC fancy/JJ ./. Some/DT variations/NNS useful/JJ to/TO him/PRP have/VBP probably/RB arisen/VBN suddenly/RB ,/, or/CC by/IN one/CD step/NN ;/: many/JJ botanists/NNS ,/, for/IN instance/NN ,/, believe/VBP that/IN the/DT fuller's/NNS teasel/NN ,/, with/IN its/PRP$ hooks/NNS ,/, which/WDT cannot/MD be/VB rivalled/VBD by/IN any/DT mechanical/JJ contrivance/NN ,/, is/VBZ only/RB a/DT variety/NN of/IN the/DT wild/JJ Dipsacus/NNP ;/: and/CC this/DT amount/NN of/IN change/NN may/MD have/VB suddenly/RB arisen/VBN in/IN a/DT seedling/VBG ./. So/RB it/PRP has/VBZ probably/RB been/VBN with/IN the/DT turnspit/NN dog/NN ;/: and/CC this/DT is/VBZ known/VBN to/TO have/VB been/VBN the/DT case/NN with/IN the/DT ancon/NN sheep/NN ./. But/CC when/WRB we/PRP compare/VB the/DT dray/NN horse/NN and/CC race/NN horse/NN ,/, the/DT dromedary/JJ and/CC camel/NN ,/, the/DT various/JJ breeds/NNS of/IN sheep/NN fitted/VBN either/DT for/IN cultivated/VBN land/NN or/CC mountain/NN pasture/NN ,/, with/IN the/DT wool/NN of/IN one/CD breed/NN good/JJ for/IN one/CD purpose/NN ,/, and/CC that/IN of/IN another/DT breed/NN for/IN another/DT purpose/NN ;/: when/WRB we/PRP compare/VB the/DT many/JJ breeds/NNS of/IN dogs/NNS ,/, each/DT good/JJ for/IN man/NN in/IN different/JJ ways/NNS ;/: when/WRB we/PRP compare/VB the/DT game/NN cock/NN ,/, so/RB pertinacious/JJ in/IN battle/NN ,/, with/IN other/JJ breeds/NNS so/RB little/JJ quarrelsome/JJ ,/, with/IN "/" everlasting/JJ layers/NNS "/" which/WDT never/RB desire/NN to/TO sit/VB ,/, and/CC with/IN the/DT bantam/NN so/RB small/JJ and/CC elegant/JJ ;/: when/WRB we/PRP compare/VB the/DT host/NN of/IN agricultural/JJ ,/, culinary/JJ ,/, orchard/NN ,/, and/CC flower/NN garden/NN races/NNS of/IN plants/NNS ,/, most/RBS useful/JJ to/TO man/NN at/IN different/JJ seasons/NNS and/CC for/IN different/JJ purposes/NNS ,/, or/CC so/RB beautiful/JJ in/IN his/PRP$ eyes/NNS ,/, we/PRP must/MD ,/, I/PRP think/VBP ,/, look/VB further/JJR than/IN to/TO mere/JJ variability/NN ./. We/PRP cannot/MD suppose/VB that/IN all/DT the/DT breeds/NNS were/VBD suddenly/RB produced/VBN as/IN perfect/JJ and/CC as/IN useful/JJ as/IN we/PRP now/RB see/VB them/PRP ;/: indeed/RB ,/, in/IN many/JJ cases/NNS ,/, we/PRP know/VB that/IN this/DT has/VBZ not/RB been/VBN their/PRP$ history/NN ./. The/DT key/JJ is/VBZ man's/NNS power/NN of/IN accumulative/JJ selection/NN :/: nature/NN gives/VBZ successive/JJ variations/NNS ;/: man/NN adds/VBZ them/PRP up/IN in/IN certain/JJ directions/NNS useful/JJ to/TO him/PRP ./. In/IN this/DT sense/NN he/PRP may/MD be/VB said/VBD to/TO have/VB made/VBN for/IN himself/PRP useful/JJ breeds/NNS ./. The/DT great/JJ power/NN of/IN this/DT principle/NN of/IN selection/NN is/VBZ not/RB hypothetical/JJ ./. It/PRP is/VBZ certain/JJ that/IN several/JJ of/IN our/PRP$ eminent/JJ breeders/NNS have/VBP ,/, even/RB within/IN a/DT single/JJ lifetime/NN ,/, modified/VBN to/TO a/DT large/JJ extent/NN their/PRP$ breeds/NNS of/IN cattle/NNS and/CC sheep/NN ./. In/IN order/NN fully/RB to/TO realise/NN what/WP they/PRP have/VBP done/VBN ,/, it/PRP is/VBZ almost/RB necessary/JJ to/TO read/VB several/JJ of/IN the/DT many/JJ treatises/NNS devoted/VBN to/TO this/DT subject/NN ,/, and/CC to/TO inspect/VB the/DT animals/NNS ./. Breeders/NNP habitually/RB speak/VB of/IN an/DT animal's/NNS organisation/NN as/IN something/NN plastic/NN ,/, which/WDT they/PRP can/MD model/NN as/IN they/PRP please/VB ./. If/IN I/PRP had/VBD space/NN I/PRP could/MD quote/VB numerous/JJ passages/NNS to/TO this/DT effect/NN from/IN highly/RB competent/JJ authorities/NNS ./. Youatt/NNP ,/, who/WP was/VBD probably/RB better/JJR acquainted/VBN with/IN the/DT works/NNS of/IN agriculturists/NNS than/IN almost/RB any/DT other/JJ individual/JJ ,/, and/CC who/WP was/VBD himself/PRP a/DT very/RB good/JJ judge/NN of/IN animals/NNS ,/, speaks/VBZ of/IN the/DT principle/NN of/IN selection/NN as/IN "/" that/IN which/WDT enables/VBZ the/DT agriculturist/NN ,/, not/RB only/RB to/TO modify/VB the/DT character/NN of/IN his/PRP$ flock/NN ,/, but/CC to/TO change/NN it/PRP altogether/RB ./. It/PRP is/VBZ the/DT magician's/NNS wand/NN ,/, by/IN means/VBZ of/IN which/WDT he/PRP may/MD summon/VB into/IN life/NN whatever/WDT form/NN and/CC mould/VB he/PRP pleases/VBZ ./. "/" Lord/NNP Somerville/NNP ,/, speaking/VBG of/IN what/WP breeders/NNS have/VBP done/VBN for/IN sheep/NN ,/, says/VBZ :/: "/" It/PRP would/MD seem/VB as/IN if/IN they/PRP had/VBD chalked/VBN out/IN upon/IN a/DT wall/NN a/DT form/NN perfect/JJ in/IN itself/PRP ,/, and/CC then/RB had/VBD given/VBN it/PRP existence/NN ./. "/" In/IN Saxony/NNP the/DT importance/NN of/IN the/DT principle/NN of/IN selection/NN in/IN regard/NN to/TO merino/NN sheep/NN is/VBZ so/RB fully/RB recognised/VBD ,/, that/IN men/NNS follow/VB it/PRP as/IN a/DT trade/NN :/: the/DT sheep/NN are/VBP placed/VBN on/IN a/DT table/NN and/CC are/VBP studied/VBN ,/, like/IN a/DT picture/NN by/IN a/DT connoisseur/NN ;/: this/DT is/VBZ done/VBN three/CD times/NNS at/IN intervals/NNS of/IN months/NNS ,/, and/CC the/DT sheep/NN are/VBP each/DT time/NN marked/VBN and/CC classed/VBN ,/, so/RB that/IN the/DT very/RB best/JJS may/MD ultimately/RB be/VB selected/VBN for/IN breeding/VBG ./. What/WP English/NNP breeders/NNS have/VBP actually/RB effected/VBN is/VBZ proved/VBN by/IN the/DT enormous/JJ prices/NNS given/VBN for/IN animals/NNS with/IN a/DT good/JJ pedigree/NN ;/: and/CC these/DT have/VBP been/VBN exported/VBN to/TO almost/RB every/DT quarter/NN of/IN the/DT world/NN ./. The/DT improvement/NN is/VBZ by/IN no/DT generally/RB due/JJ to/TO crossing/VBG different/JJ breeds/NNS ;/: all/DT the/DT best/JJS breeders/NNS are/VBP strongly/RB opposed/VBN to/TO this/DT practice/NN ,/, except/IN sometimes/RB amongst/IN closely/RB allied/VBN sub/NN breeds/NNS ./. And/CC when/WRB a/DT cross/VB has/VBZ been/VBN made/VBN ,/, the/DT closest/JJS selection/NN is/VBZ far/RB more/JJR indispensable/JJ even/RB than/IN in/IN ordinary/JJ cases/NNS ./. If/IN selection/NN consisted/VBD merely/RB in/IN separating/VBG some/DT very/RB distinct/JJ variety/NN ,/, and/CC breeding/VBG from/IN it/PRP ,/, the/DT principle/NN would/MD be/VB so/RB obvious/JJ as/IN hardly/RB to/TO be/VB worth/JJ notice/NN ;/: but/CC its/PRP$ importance/NN consists/VBZ in/IN the/DT great/JJ effect/NN produced/VBN by/IN the/DT accumulation/NN in/IN one/CD direction/NN ,/, during/IN successive/JJ generations/NNS ,/, of/IN differences/NNS absolutely/RB inappreciable/JJ by/IN an/DT uneducated/JJ eye/NN differences/NNS which/WDT I/PRP for/IN one/CD have/VBP vainly/RB attempted/VBD to/TO appreciate/VB ./. Not/RB one/CD man/NN in/IN a/DT thousand/CD has/VBZ accuracy/NN of/IN eye/NN and/CC judgment/NN sufficient/JJ to/TO become/VB an/DT eminent/JJ breeder/NN ./. If/IN ,/, gifted/JJ with/IN these/DT qualities/NNS ,/, he/PRP studies/NNS his/PRP$ subject/NN for/IN years/NNS ,/, and/CC devotes/VBZ his/PRP$ lifetime/NN to/TO it/PRP with/IN indomitable/JJ perseverance/NN ,/, he/PRP will/MD succeed/VB ,/, and/CC may/MD make/VB great/JJ improvements/NNS ;/: if/IN he/PRP wants/VBZ any/DT of/IN these/DT qualities/NNS ,/, he/PRP will/MD assuredly/RB fail/VB ./. Few/JJ would/MD readily/RB believe/VBP in/IN the/DT natural/JJ capacity/NN and/CC years/NNS of/IN practice/NN requisite/JJ to/TO become/VB even/RB a/DT skilful/JJ pigeon/NN fancier/JJR ./. The/DT same/JJ principles/NNS are/VBP followed/VBD by/IN horticulturists/NNS ;/: but/CC the/DT variations/NNS are/VBP here/RB often/RB more/JJR abrupt/JJ ./. No/DT one/CD supposes/VBZ that/IN our/PRP$ choicest/JJS productions/NNS have/VBP been/VBN produced/VBN by/IN a/DT single/JJ variation/NN from/IN the/DT aboriginal/JJ stock/NN ./. We/PRP have/VBP proofs/NNS that/IN this/DT has/VBZ not/RB been/VBN so/RB in/IN several/JJ cases/NNS in/IN which/WDT exact/JJ records/NNS have/VBP been/VBN kept/VBD ;/: thus/RB ,/, to/TO give/VB a/DT very/RB trifling/JJ instance/NN ,/, the/DT steadily/RB increasing/VBG size/NN of/IN the/DT common/JJ gooseberry/NN may/MD be/VB quoted/VBN ./. We/PRP see/VB an/DT astonishing/JJ improvement/NN in/IN many/JJ florists'/NN flowers/NNS ,/, when/WRB the/DT flowers/NNS of/IN the/DT present/JJ day/NN are/VBP compared/VBN with/IN drawings/NNS made/VBN only/RB twenty/CD or/CC thirty/CD years/NNS ago/RB ./. When/WRB a/DT race/NN of/IN plants/NNS is/VBZ once/RB pretty/RB well/RB established/VBN ,/, the/DT seed/NN raisers/NNS do/VBP not/RB pick/VB out/IN the/DT best/JJS plants/NNS ,/, but/CC merely/RB go/VB over/IN their/PRP$ seed/NN beds/NNS ,/, and/CC pull/VB up/IN the/DT "/" rogues/NNS ,/, "/" as/IN they/PRP call/VB the/DT plants/NNS that/IN deviate/VB from/IN the/DT proper/JJ standard/JJ ./. 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Nor/CC must/MD the/DT value/NN which/WDT would/MD formerly/RB have/VBP been/VBN set/VBN on/IN any/DT slight/JJ differences/NNS in/IN the/DT individuals/NNS of/IN the/DT same/JJ species/NN ,/, be/VB judged/VBN of/IN by/IN the/DT value/NN which/WDT is/VBZ now/RB set/VBN on/IN them/PRP ,/, after/IN several/JJ breeds/NNS have/VBP fairly/RB been/VBN established/VBN ./. I/PRP is/VBZ known/VBN that/IN with/IN pigeons/NNS many/JJ slight/JJ variations/NNS now/RB occasionally/RB appear/VB ,/, but/CC these/DT are/VBP rejected/VBD as/IN faults/NNS or/CC deviations/NNS from/IN the/DT standard/JJ of/IN perfection/NN in/IN each/DT breed/NN ./. The/DT common/JJ goose/NN has/VBZ not/RB given/VBN rise/NN to/TO any/DT marked/VBN varieties/NNS ;/: hence/RB the/DT Toulouse/NNP and/CC the/DT common/JJ breed/NN ,/, which/WDT differ/VBP only/RB in/IN colour/NN ,/, that/IN most/RBS fleeting/JJ of/IN characters/NNS ,/, have/VBP lately/RB been/VBN exhibited/VBN as/IN distinct/JJ at/IN our/PRP$ poultry/NN shows/VBZ ./. These/DT views/NNS appear/VB to/TO explain/VB what/WP has/VBZ sometimes/RB been/VBN noticed/VBD namely/RB ,/, that/IN we/PRP know/VB hardly/RB anything/NN about/IN the/DT origin/NN or/CC history/NN of/IN any/DT of/IN our/PRP$ domestic/JJ breeds/NNS ./. But/CC ,/, in/IN fact/NN ,/, a/DT breed/NN ,/, like/IN a/DT dialect/NN of/IN a/DT language/NN ,/, can/MD hardly/RB be/VB said/VBD to/TO have/VB a/DT distinct/JJ origin/NN ./. man/NN preserves/VBZ and/CC breeds/NNS from/IN an/DT individual/JJ with/IN some/DT slight/JJ deviation/NN of/IN structure/NN ,/, or/CC takes/VBZ more/JJR care/NN than/IN usual/JJ in/IN matching/VBG his/PRP$ best/JJS animals/NNS ,/, and/CC thus/RB improves/VBZ them/PRP ,/, and/CC the/DT improved/VBN animals/NNS slowly/RB spread/NN in/IN the/DT immediate/JJ neighbourhood/NN ./. But/CC they/PRP will/MD as/IN yet/RB hardly/RB have/VBP a/DT distinct/JJ name/NN ,/, and/CC from/IN being/VBG only/RB slightly/RB valued/VBN ,/, their/PRP$ history/NN will/MD have/VB been/VBN disregarded/VBD ./. When/WRB further/JJR improved/VBN by/IN the/DT same/JJ slow/JJ and/CC gradual/JJ process/NN ,/, they/PRP will/MD spread/NN more/JJR widely/RB ,/, and/CC will/MD be/VB recognised/VBD as/IN something/NN distinct/JJ and/CC valuable/JJ ,/, and/CC will/MD then/RB probably/RB first/JJ receive/VB a/DT provincial/JJ name/NN ./. In/IN semi/NN civilised/JJ countries/NNS ,/, with/IN little/JJ free/JJ communication/NN ,/, the/DT spreading/VBG of/IN a/DT new/JJ sub/NN breed/NN would/MD be/VB a/DT slow/JJ process/NN ./. As/IN soon/RB as/IN the/DT points/NNS of/IN value/NN are/VBP once/RB acknowledged/VBD ,/, the/DT principle/NN ,/, as/IN I/PRP have/VBP called/VBN it/PRP ,/, of/IN unconscious/JJ selection/NN will/MD always/RB tend/VBP ,/, perhaps/RB more/JJR at/IN one/CD period/NN than/IN at/IN another/DT ,/, as/IN the/DT breed/NN rises/VBZ or/CC falls/VBZ in/IN fashion/NN ,/, perhaps/RB more/JJR in/IN one/CD district/NN than/IN in/IN another/DT ,/, according/VBG to/TO the/DT state/NN of/IN civilisation/NN of/IN the/DT inhabitants/NNS ,/, slowly/RB to/TO add/VB to/TO the/DT characteristic/JJ features/NNS of/IN the/DT breed/NN ,/, whatever/WDT they/PRP may/MD be/VB ./. But/CC the/DT chance/NN will/MD be/VB infinitely/RB small/JJ of/IN any/DT record/NN having/VBG been/VBN preserved/VBN of/IN such/JJ slow/JJ ,/, varying/VBG ,/, and/CC insensible/JJ changes/NNS ./. Circumstances/NNS favourable/JJ to/TO Man's/NNP Power/NNP of/IN Selection/NN I/PRP will/MD now/RB say/VBP a/DT few/JJ words/NNS on/IN the/DT circumstances/NNS ,/, favourable/JJ ,/, or/CC the/DT reverse/VB ,/, to/TO man's/NNS power/NN of/IN selection/NN ./. A/DT high/JJ degree/NN of/IN variability/NN is/VBZ obviously/RB favourable/JJ ,/, as/IN freely/RB giving/VBG the/DT materials/NNS for/IN selection/NN to/TO work/NN on/IN ;/: not/RB that/IN mere/JJ individual/JJ differences/NNS are/VBP not/RB amply/RB sufficient/JJ ,/, with/IN extreme/JJ care/NN ,/, to/TO allow/VB of/IN the/DT accumulation/NN of/IN a/DT large/JJ amount/NN of/IN modification/NN in/IN almost/RB any/DT desired/VBN direction/NN ./. But/CC as/IN variations/NNS manifestly/RB useful/JJ or/CC pleasing/JJ to/TO man/NN appear/VB only/RB occasionally/RB ,/, the/DT chance/NN of/IN their/PRP$ appearance/NN will/MD be/VB much/JJ increased/VBN by/IN a/DT large/JJ number/NN of/IN individuals/NNS being/VBG kept/VBD ./. Hence/RB ,/, number/NN is/VBZ of/IN the/DT highest/JJS importance/NN for/IN success/NN ./. On/IN this/DT principle/NN Marshall/NNP formerly/RB remarked/VBD ,/, with/IN respect/NN to/TO the/DT sheep/NN of/IN parts/NNS of/IN Yorkshire/NNP ,/, "/" as/IN they/PRP generally/RB belong/VB to/TO poor/JJ people/NNS ,/, and/CC are/VBP mostly/RB in/IN small/JJ lots/NNS ,/, they/PRP never/RB can/MD be/VB improved/VBN ./. "/" On/IN the/DT other/JJ hand/NN ,/, nurserymen/NNS ,/, from/IN keeping/VBG large/JJ stocks/NNS of/IN the/DT same/JJ plant/NN ,/, are/VBP generally/RB far/RB more/JJR successful/JJ than/IN amateurs/NNS in/IN raising/VBG new/JJ and/CC valuable/JJ varieties/NNS ./. A/DT large/JJ number/NN of/IN individuals/NNS of/IN an/DT animal/NN or/CC plant/NN can/MD be/VB reared/VBD only/RB where/WRB the/DT conditions/NNS for/IN its/PRP$ propagation/NN are/VBP favourable/JJ ./. 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No/DT doubt/NN the/DT strawberry/NN had/VBD always/RB varied/VBN since/IN it/PRP was/VBD cultivated/VBN ,/, but/CC the/DT slightest/JJS varieties/NNS had/VBD been/VBN neglected/VBN ./. As/IN soon/RB ,/, however/RB ,/, as/IN gardeners/NNS picked/VBD out/IN individual/JJ plants/NNS with/IN slightly/RB larger/JJR ,/, earlier/RBR ,/, or/CC better/JJR fruit/NN ,/, and/CC raised/VBN seedlings/NNS from/IN them/PRP ,/, and/CC again/RB picked/VBD out/IN the/DT best/JJS seedlings/NNS and/CC bred/VBN from/IN them/PRP ,/, then/RB (/( with/IN some/DT aid/NN by/IN crossing/VBG distinct/JJ species/NN )/SYM those/DT many/JJ admirable/JJ varieties/NNS of/IN the/DT strawberry/NN were/VBD raised/VBN which/WDT have/VBP appeared/VBD during/IN the/DT last/JJ half/NN century/NN ./. With/IN animals/NNS ,/, facility/NN in/IN preventing/VBG crosses/VBZ is/VBZ an/DT important/JJ element/NN in/IN the/DT formation/NN of/IN new/JJ races/NNS ,/, at/IN least/JJS ,/, in/IN a/DT country/NN which/WDT is/VBZ already/RB stocked/VBN with/IN other/JJ races/NNS ./. In/IN this/DT respect/NN enclosure/NN of/IN the/DT land/NN plays/VBZ a/DT part/NN ./. Wandering/VBG savages/NNS or/CC the/DT inhabitants/NNS of/IN open/JJ plains/NNS rarely/RB possess/VBP more/JJR than/IN one/CD breed/NN of/IN the/DT same/JJ species/NN ./. Pigeons/NNP can/MD be/VB mated/VBN for/IN life/NN ,/, and/CC this/DT is/VBZ a/DT great/JJ convenience/NN to/TO the/DT fancier/JJR ,/, for/IN thus/RB many/JJ races/NNS may/MD be/VB improved/VBN and/CC kept/VBD true/JJ ,/, though/IN mingled/VBD in/IN the/DT same/JJ aviary/NN ;/: and/CC this/DT circumstance/NN must/MD have/VB largely/RB favoured/VBN the/DT formation/NN of/IN new/JJ breeds/NNS ./. Pigeons/NNP ,/, I/PRP may/MD add/VB ,/, can/MD be/VB propagated/VBN in/IN great/JJ numbers/NNS and/CC at/IN a/DT very/RB quick/JJ rate/NN ,/, and/CC inferior/JJ birds/NNS may/MD be/VB freely/RB rejected/VBD ,/, as/IN when/WRB killed/VBN they/PRP serve/VB for/IN food/NN ./. On/IN the/DT other/JJ hand/NN ,/, cats/NNS from/IN their/PRP$ nocturnal/JJ rambling/NN habits/NNS cannot/MD be/VB easily/RB matched/VBN ,/, and/CC ,/, although/IN so/RB much/JJ valued/VBN by/IN women/NNS and/CC children/NNS ,/, we/PRP rarely/RB see/VB a/DT distinct/JJ breed/NN long/JJ kept/VBD up/IN ;/: such/JJ breeds/NNS as/IN we/PRP do/VBP sometimes/RB see/VB are/VBP almost/RB always/RB imported/VBN from/IN some/DT other/JJ country/NN ./. Although/IN I/PRP do/VBP not/RB doubt/NN that/IN some/DT domestic/JJ animals/NNS vary/VBP less/JJR than/IN others/NNS ,/, yet/RB the/DT rarity/NN or/CC absence/NN of/IN distinct/JJ breeds/NNS of/IN the/DT cat/NN ,/, the/DT donkey/NN ,/, peacock/NN ,/, goose/NN ,/, &c/NN ./. ,/, may/MD be/VB attributed/VBD in/IN main/JJ part/NN to/TO selection/NN not/RB having/VBG been/VBN brought/VBN into/IN play/VB :/: in/IN cats/NNS ,/, from/IN the/DT difficulty/NN in/IN pairing/NN them/PRP ;/: in/IN donkeys/NNS ,/, from/IN only/RB a/DT few/JJ being/VBG kept/VBD by/IN poor/JJ people/NNS ,/, and/CC little/JJ attention/NN paid/VBN to/TO their/PRP$ breeding/VBG ;/: for/IN recently/RB in/IN certain/JJ parts/NNS of/IN Spain/NNP and/CC of/IN the/DT United/NNP States/NNPS this/DT animal/NN has/VBZ been/VBN surprisingly/RB modified/VBN and/CC improved/VBN by/IN careful/JJ selection/NN :/: in/IN peacocks/NNS ,/, from/IN not/RB being/VBG very/RB easily/RB reared/VBD and/CC a/DT large/JJ stock/NN not/RB kept/VBD :/: in/IN geese/NNS ,/, from/IN being/VBG valuable/JJ only/RB for/IN two/CD purposes/NNS ,/, food/NN and/CC feathers/NNS ,/, and/CC more/JJR especially/RB from/IN no/DT pleasure/NN having/VBG been/VBN felt/VBD in/IN the/DT display/NN of/IN distinct/JJ breeds/NNS ;/: but/CC the/DT goose/NN ,/, under/IN the/DT conditions/NNS to/TO which/WDT it/PRP is/VBZ exposed/VBN when/WRB domesticated/VBN seems/VBZ to/TO have/VB a/DT singularly/RB inflexible/JJ organisation/NN ,/, though/IN it/PRP has/VBZ varied/VBN to/TO a/DT slight/JJ extent/NN ,/, as/IN I/PRP have/VBP elsewhere/RB described/VBN ./. 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Wallace/NNP has/VBZ remarked/VBN with/IN much/JJ truth/NN ,/, a/DT limit/NN will/MD be/VB at/IN last/JJ reached/VBN ./. For/IN instance/NN ,/, there/EX must/MD be/VB a/DT limit/NN to/TO the/DT fleetness/NN of/IN any/DT terrestrial/JJ animal/NN ,/, as/IN this/DT will/MD be/VB determined/VBN by/IN the/DT friction/NN to/TO be/VB overcome/VB ,/, the/DT weight/NN of/IN body/NN to/TO be/VB carried/VBD ,/, and/CC the/DT power/NN of/IN contraction/NN in/IN the/DT muscular/JJ fibres/NNS ./. But/CC what/WP concerns/NNS us/PRP is/VBZ that/IN the/DT domestic/JJ varieties/NNS of/IN the/DT same/JJ species/NN differ/VBP from/IN each/DT other/JJ in/IN almost/RB every/DT character/NN ,/, which/WDT man/NN has/VBZ attended/VBN to/TO and/CC selected/VBN ,/, more/JJR than/IN do/VBP the/DT distinct/JJ species/NN of/IN the/DT same/JJ genera/NN ./. 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Generally/RB the/DT term/NN includes/VBZ the/DT unknown/JJ element/NN of/IN a/DT distant/JJ act/NN of/IN creation/NN ./. The/DT term/NN "/" variety/NN "/" is/VBZ almost/RB equally/RB difficult/JJ to/TO define/VB ;/: but/CC here/RB community/NN of/IN descent/NN is/VBZ almost/RB universally/RB implied/VBN ,/, though/IN it/PRP can/MD rarely/RB be/VB proved/VBD ./. We/PRP have/VBP also/RB what/WP are/VBP called/VBN monstrosities/NNS ;/: but/CC they/PRP graduate/NN into/IN varieties/NNS ./. By/IN a/DT monstrosity/NN I/PRP presume/VB is/VBZ meant/VBN some/DT considerable/JJ deviation/NN of/IN structure/NN ,/, generally/RB injurious/JJ ,/, or/CC not/RB useful/JJ to/TO the/DT species/NN ./. 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No/DT one/CD ever/RB had/VBD more/JJR ample/JJ materials/NNS for/IN the/DT discrimination/NN of/IN the/DT species/NN ,/, or/CC could/MD have/VB worked/VBD on/IN them/PRP with/IN more/JJR zeal/NN and/CC sagacity/NN ./. He/PRP first/JJ gives/VBZ in/IN detail/NN all/DT the/DT many/JJ points/NNS of/IN structure/NN which/WDT vary/VBP in/IN the/DT several/JJ species/NN ,/, and/CC estimates/NNS numerically/RB the/DT relative/JJ frequency/NN of/IN the/DT variations/NNS ./. He/PRP specifies/VBZ above/IN a/DT dozen/NN characters/NNS which/WDT may/MD be/VB found/VBD varying/VBG even/RB on/IN the/DT same/JJ branch/NN ,/, sometimes/RB according/VBG to/TO age/NN or/CC development/NN ,/, sometimes/RB without/IN any/DT assignable/JJ reason/NN ./. Such/JJ characters/NNS are/VBP not/RB of/IN course/NN of/IN specific/JJ value/NN ,/, but/CC they/PRP are/VBP ,/, as/IN Asa/NNP Gray/NNP has/VBZ remarked/VBN in/IN commenting/VBG on/IN this/DT memoir/NN ,/, such/JJ as/IN generally/RB enter/VB into/IN specific/JJ definitions/NNS ./. De/NNP Candolle/NNP then/RB goes/VBZ on/IN to/TO say/VB that/IN he/PRP gives/VBZ the/DT rank/NN of/IN species/NN to/TO the/DT forms/NNS that/IN differ/VBP by/IN characters/NNS never/RB varying/VBG on/IN the/DT same/JJ tree/NN ,/, and/CC never/RB found/VBD connected/VBN by/IN intermediate/JJ states/NNS ./. After/IN this/DT discussion/NN ,/, the/DT result/NN of/IN so/RB much/JJ labour/NN ,/, he/PRP emphatically/RB remarks/NNS :/: "/" They/PRP are/VBP mistaken/VBN ,/, who/WP repeat/VB that/IN the/DT greater/JJR part/NN of/IN our/PRP$ species/NN are/VBP clearly/RB limited/JJ ,/, and/CC that/IN the/DT doubtful/JJ species/NN are/VBP in/IN a/DT feeble/JJ minority/NN ./. This/DT seemed/VBD to/TO be/VB true/JJ ,/, so/RB long/JJ as/IN a/DT genus/NN was/VBD imperfectly/RB known/VBN ,/, and/CC its/PRP$ species/NN were/VBD founded/VBN upon/IN a/DT few/JJ specimens/NNS ,/, that/IN is/VBZ to/TO say/VB ,/, were/VBD provisional/JJ ./. Just/RB as/IN we/PRP come/VB to/TO know/VB them/PRP better/JJR ,/, intermediate/JJ forms/NNS flow/NN in/IN ,/, and/CC doubts/NNS as/IN to/TO specific/JJ limits/NNS augment/VB ./. "/" He/PRP also/RB adds/VBZ that/IN it/PRP is/VBZ the/DT best/JJS known/VBN species/NN which/WDT present/JJ the/DT greater/JJR number/NN of/IN spontaneous/JJ varieties/NNS and/CC sub/NN varieties/NNS ./. Thus/RB Quercus/NNP robur/NN has/VBZ twenty/CD eight/CD varieties/NNS ,/, all/DT of/IN which/WDT ,/, excepting/VBG six/CD ,/, are/VBP clustered/VBN round/NN three/CD sub/NN species/NN ,/, namely/RB ,/, Q/NN ./. pedunculata/NN ,/, sessiliflora/NN ,/, and/CC pubescens/NNS ./. 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"/" When/WRB a/DT young/JJ naturalist/NN commences/VBZ the/DT study/NN of/IN a/DT group/NN of/IN organisms/NNS quite/RB unknown/JJ to/TO him/PRP ,/, he/PRP is/VBZ at/IN first/JJ much/JJ perplexed/JJ in/IN determining/VBG what/WP differences/NNS to/TO consider/VB as/IN specific/JJ ,/, and/CC what/WP as/IN varietal/JJ ;/: for/IN he/PRP knows/VBZ nothing/NN of/IN the/DT amount/NN and/CC kind/NN of/IN variation/NN to/TO which/WDT the/DT group/NN is/VBZ subject/NN ;/: and/CC this/DT shows/VBZ ,/, at/IN least/JJS ,/, how/WRB very/RB generally/RB there/EX is/VBZ some/DT variation/NN ./. But/CC if/IN he/PRP confine/VB his/PRP$ attention/NN to/TO one/CD class/NN within/IN one/CD country/NN ,/, he/PRP will/MD soon/RB make/VB up/IN his/PRP$ mind/NN how/WRB to/TO rank/NN most/RBS of/IN the/DT doubtful/JJ forms/NNS ./. 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We/PRP behold/VB the/DT face/NN of/IN nature/NN bright/JJ with/IN gladness/NN ,/, we/PRP often/RB see/VB superabundance/NN of/IN food/NN ;/: we/PRP do/VBP not/RB see/VB or/CC we/PRP forget/VB ,/, that/IN the/DT birds/NNS which/WDT are/VBP idly/RB singing/VBG round/NN us/PRP mostly/RB live/VB on/IN insects/NNS or/CC seeds/NNS ,/, and/CC are/VBP thus/RB constantly/RB destroying/VBG life/NN ;/: or/CC we/PRP forget/VB how/WRB largely/RB these/DT songsters/NNS ,/, or/CC their/PRP$ eggs/NNS ,/, or/CC their/PRP$ nestlings/NNS ,/, are/VBP destroyed/VBN by/IN birds/NNS and/CC beasts/NNS of/IN prey/NN ;/: we/PRP do/VBP not/RB always/RB bear/VB in/IN mind/NN ,/, that/IN ,/, though/IN food/NN may/MD be/VB now/RB superabundant/NN ,/, it/PRP is/VBZ not/RB so/RB at/IN all/DT seasons/NNS of/IN each/DT recurring/VBG year/NN ./. The/DT Term/NN ,/, Struggle/NNP for/IN Existence/NN ,/, used/VBN in/IN a/DT large/JJ sense/NN I/PRP should/MD premise/NN that/IN I/PRP use/NN this/DT term/NN in/IN a/DT large/JJ and/CC metaphorical/JJ sense/NN including/VBG dependence/NN of/IN one/CD being/VBG on/IN another/DT ,/, and/CC including/VBG (/( which/WDT is/VBZ more/JJR important/JJ )/SYM not/RB only/RB the/DT life/NN of/IN the/DT individual/JJ ,/, but/CC success/NN in/IN leaving/VBG progeny/NN ./. Two/CD canine/JJ animals/NNS ,/, in/IN a/DT time/NN of/IN dearth/NN may/MD be/VB truly/RB said/VBD to/TO struggle/NN with/IN each/DT other/JJ which/WDT shall/MD get/VB food/NN and/CC live/VB ./. But/CC a/DT plant/NN on/IN the/DT edge/NN of/IN a/DT desert/NN is/VBZ said/VBD to/TO struggle/NN for/IN life/NN against/IN the/DT drought/NN ,/, though/IN more/JJR properly/RB it/PRP should/MD be/VB said/VBD to/TO be/VB dependent/JJ on/IN the/DT moisture/NN ./. 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As/IN the/DT mistletoe/NN is/VBZ disseminated/VBN by/IN birds/NNS ,/, its/PRP$ existence/NN depends/VBZ on/IN them/PRP ;/: and/CC it/PRP may/MD methodically/RB be/VB said/VBD to/TO struggle/NN with/IN other/JJ fruit/NN bearing/VBG plants/NNS ,/, in/IN tempting/JJ the/DT birds/NNS to/TO devour/VB and/CC thus/RB disseminate/VB its/PRP$ seeds/NNS ./. In/IN these/DT several/JJ senses/NNS ,/, which/WDT pass/VB into/IN each/DT other/JJ ,/, I/PRP use/NN for/IN convenience'/NN sake/NN the/DT general/JJ term/NN of/IN Struggle/NNP for/IN Existence/NN ./. Geometrical/NNP Ratio/NNP of/IN Increase/VB A/DT struggle/NN for/IN existence/NN inevitably/RB follows/VBZ from/IN the/DT high/JJ rate/NN at/IN which/WDT all/DT organic/JJ beings/NNS tend/VBP to/TO increase/NN ./. 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But/CC this/DT is/VBZ a/DT false/JJ view/NN ;/: we/PRP forget/VB that/IN each/DT species/NN ,/, even/RB where/WRB it/PRP most/RBS abounds/VBZ ,/, is/VBZ constantly/RB suffering/VBG enormous/JJ destruction/NN at/IN some/DT period/NN of/IN its/PRP$ life/NN ,/, from/IN enemies/NNS or/CC from/IN competitors/NNS for/IN the/DT same/JJ place/NN and/CC food/NN ;/: and/CC if/IN these/DT enemies/NNS or/CC competitors/NNS be/VB in/IN the/DT least/JJS degree/NN favoured/VBN by/IN any/DT slight/JJ change/NN of/IN climate/NN ,/, they/PRP will/MD increase/NN in/IN numbers/NNS ;/: and/CC as/IN each/DT area/NN is/VBZ already/RB fully/RB stocked/VBN with/IN inhabitants/NNS ,/, the/DT other/JJ species/NN must/MD decrease/NN ./. When/WRB we/PRP travel/NN southward/RB and/CC see/VB a/DT species/NN decreasing/VBG in/IN numbers/NNS ,/, we/PRP may/MD feel/VB sure/JJ that/IN the/DT cause/NN lies/VBZ quite/RB as/IN much/JJ in/IN other/JJ species/NN being/VBG favoured/VBN ,/, as/IN in/IN this/DT one/CD being/VBG hurt/VBN ./. So/RB it/PRP is/VBZ when/WRB we/PRP travel/NN northward/RB ,/, but/CC in/IN a/DT somewhat/RB lesser/JJR degree/NN ,/, for/IN the/DT number/NN of/IN species/NN of/IN all/DT kinds/NNS ,/, and/CC therefore/RB of/IN competitors/NNS ,/, decreases/NNS northwards/NNS ;/: hence/RB in/IN going/VBG northwards/NNS ,/, or/CC in/IN ascending/VBG a/DT mountain/NN ,/, we/PRP far/RB oftener/RBR meet/VB with/IN stunted/VBN forms/NNS ,/, due/JJ to/TO the/DT directly/RB injurious/JJ action/NN of/IN climate/NN ,/, than/IN we/PRP do/VBP in/IN proceeding/NN southwards/NNS or/CC in/IN descending/VBG a/DT mountain/NN ./. 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This/DT view/NN of/IN the/DT necessity/NN of/IN a/DT large/JJ stock/NN of/IN the/DT same/JJ species/NN for/IN its/PRP$ preservation/NN ,/, explains/VBZ ,/, I/PRP believe/VBP ,/, some/DT singular/JJ facts/NNS in/IN nature/NN ,/, such/JJ as/IN that/IN of/IN very/RB rare/JJ plants/NNS being/VBG sometimes/RB extremely/RB abundant/JJ ,/, in/IN the/DT few/JJ spots/NNS where/WRB they/PRP do/VBP exist/VB ;/: and/CC that/IN of/IN some/DT social/JJ plants/NNS being/VBG social/JJ ,/, that/IN is/VBZ abounding/VBG in/IN individuals/NNS ,/, even/RB on/IN the/DT extreme/JJ verge/NN of/IN their/PRP$ range/NN ./. For/IN in/IN such/JJ cases/NNS ,/, we/PRP may/MD believe/VB ,/, that/IN a/DT plant/NN could/MD exist/VB only/RB where/WRB the/DT conditions/NNS of/IN its/PRP$ life/NN were/VBD so/RB favourable/JJ that/IN many/JJ could/MD exist/VB together/RB ,/, and/CC thus/RB save/VB the/DT species/NN from/IN utter/JJ destruction/NN ./. 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In/IN Staffordshire/NNP ,/, on/IN the/DT estate/NN of/IN a/DT relation/NN ,/, where/WRB I/PRP had/VBD ample/JJ means/VBZ of/IN investigation/NN ,/, there/EX was/VBD a/DT large/JJ and/CC extremely/RB barren/JJ heath/NN ,/, which/WDT had/VBD never/RB been/VBN touched/VBD by/IN the/DT hand/NN of/IN man/NN ;/: but/CC several/JJ hundred/CD acres/NNS of/IN exactly/RB the/DT same/JJ nature/NN had/VBD been/VBN enclosed/VBN twenty/CD five/CD years/NNS previously/RB and/CC planted/VBN with/IN Scotch/NNP fir/NN ./. 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When/WRB I/PRP ascertained/VBN that/IN these/DT young/JJ trees/NNS had/VBD not/RB been/VBN sown/VBN or/CC planted/VBN ,/, I/PRP was/VBD so/RB much/JJ surprised/VBN at/IN their/PRP$ numbers/NNS that/IN I/PRP went/VBD to/TO several/JJ points/NNS of/IN view/NN ,/, whence/WRB I/PRP could/MD examine/VB hundreds/NNS of/IN acres/NNS of/IN the/DT unenclosed/JJ heath/NN ,/, and/CC literally/RB I/PRP could/MD not/RB see/VB a/DT single/JJ Scotch/NNP fir/NN ,/, except/IN the/DT old/JJ planted/VBN clumps/NNS ./. But/CC on/IN looking/VBG closely/RB between/IN the/DT stems/VBZ of/IN the/DT heath/NN ,/, I/PRP found/VBD a/DT multitude/NN of/IN seedlings/NNS and/CC little/JJ trees/NNS which/WDT had/VBD been/VBN perpetually/RB browsed/VBN down/RB by/IN the/DT cattle/NNS ./. 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Here/RB we/PRP see/VB that/IN cattle/NNS absolutely/RB determine/VB the/DT existence/NN of/IN the/DT Scotch/NNP fir/NN ;/: but/CC in/IN several/JJ parts/NNS of/IN the/DT world/NN insects/NNS determine/VB the/DT existence/NN of/IN cattle/NNS ./. Perhaps/RB Paraguay/NNP offers/VBZ the/DT most/RBS curious/JJ instance/NN of/IN this/DT ;/: for/IN here/RB neither/DT cattle/NNS nor/CC horses/NNS nor/CC dogs/NNS have/VBP ever/RB run/VB wild/JJ ,/, though/IN they/PRP swarm/NN southward/RB and/CC northward/RB in/IN a/DT feral/JJ state/NN ;/: and/CC Azara/NNP and/CC Rengger/NNP have/VBP shown/VBN that/IN this/DT is/VBZ caused/VBN by/IN the/DT greater/JJR number/NN in/IN Paraguay/NNP of/IN a/DT certain/JJ fly/VB ,/, which/WDT lays/VBZ its/PRP$ eggs/NNS in/IN the/DT navels/NNS of/IN these/DT animals/NNS when/WRB first/JJ born/VBN ./. 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Probably/RB in/IN no/DT single/JJ instance/NN should/MD we/PRP know/VB what/WP to/TO do/VB ./. This/DT ought/MD to/TO convince/VB us/PRP of/IN our/PRP$ ignorance/NN on/IN the/DT mutual/JJ relations/NNS of/IN all/DT organic/JJ beings/NNS ;/: a/DT conviction/NN as/IN necessary/JJ as/IN it/PRP is/VBZ difficult/JJ to/TO acquire/VB ./. All/DT that/IN we/PRP can/MD do/VB ,/, is/VBZ to/TO keep/VB steadily/RB in/IN mind/NN that/IN each/DT organic/JJ being/VBG is/VBZ striving/VBG to/TO increase/NN in/IN a/DT geometrical/JJ ratio/NN ;/: that/IN each/DT at/IN some/DT period/NN of/IN its/PRP$ life/NN ,/, during/IN some/DT season/NN of/IN the/DT year/NN ,/, during/IN each/DT generation/NN or/CC at/IN intervals/NNS ,/, has/VBZ to/TO struggle/NN for/IN life/NN and/CC to/TO suffer/VB great/JJ destruction/NN ./. 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Let/VB the/DT endless/JJ number/NN of/IN slight/JJ variations/NNS and/CC individual/JJ differences/NNS occurring/VBG in/IN our/PRP$ domestic/JJ productions/NNS ,/, and/CC ,/, in/IN a/DT lesser/JJR degree/NN ,/, in/IN those/DT under/IN nature/NN ,/, be/VB borne/VBN in/IN mind/NN ;/: as/IN well/RB as/IN the/DT strength/NN of/IN the/DT hereditary/JJ tendency/NN ./. Under/IN domestication/NN ,/, it/PRP may/MD be/VB truly/RB said/VBD that/IN the/DT whole/JJ organisation/NN becomes/VBZ in/IN some/DT degree/NN plastic/NN ./. But/CC the/DT variability/NN ,/, which/WDT we/PRP almost/RB universally/RB meet/VB with/IN in/IN our/PRP$ domestic/JJ productions/NNS ,/, is/VBZ not/RB directly/RB produced/VBN ,/, as/IN Hooker/NNP and/CC Asa/NNP Gray/NNP have/VBP well/RB remarked/VBD ,/, by/IN man/NN ;/: he/PRP can/MD neither/DT originate/VB varieties/NNS ,/, nor/CC prevent/VB their/PRP$ occurrence/NN ;/: he/PRP can/MD preserve/VB and/CC accumulate/VB such/JJ as/IN do/VBP occur/VB ./. Unintentionally/RB he/PRP exposes/VBZ organic/JJ beings/NNS to/TO new/JJ and/CC changing/VBG conditions/NNS of/IN life/NN ,/, and/CC variability/NN ensues/VBZ ;/: but/CC similar/JJ changes/NNS of/IN conditions/NNS might/MD and/CC do/VBP occur/VB under/IN nature/NN ./. Let/VB it/PRP also/RB be/VB borne/VBN in/IN mind/NN how/WRB infinitely/RB complex/JJ and/CC close/VB fitting/JJ are/VBP the/DT mutual/JJ relations/NNS of/IN all/DT organic/JJ beings/NNS to/TO each/DT other/JJ and/CC to/TO their/PRP$ physical/JJ conditions/NNS of/IN life/NN ;/: and/CC consequently/RB what/WP infinitely/RB varied/VBN diversities/NNS of/IN structure/NN might/MD be/VB of/IN use/NN to/TO each/DT being/VBG under/IN changing/VBG conditions/NNS of/IN life/NN ./. Can/MD it/PRP ,/, then/RB ,/, be/VB thought/VBD improbable/JJ ,/, seeing/VBG that/IN variations/NNS useful/JJ to/TO man/NN have/VBP undoubtedly/RB occurred/VBD ,/, that/IN other/JJ variations/NNS useful/JJ in/IN some/DT way/NN to/TO each/DT being/VBG in/IN the/DT great/JJ and/CC complex/JJ battle/NN of/IN life/NN ,/, should/MD occur/VB in/IN the/DT course/NN of/IN many/JJ successive/JJ generations/NNS ?/. If/IN such/JJ do/VBP occur/VB ,/, can/MD we/PRP doubt/NN (/( remembering/VBG that/IN many/JJ more/JJR individuals/NNS are/VBP born/VBN than/IN can/MD possibly/RB survive/VB )/SYM that/IN individuals/NNS having/VBG any/DT advantage/NN ,/, however/RB slight/JJ ,/, over/IN others/NNS ,/, would/MD have/VB the/DT best/JJS chance/NN of/IN surviving/VBG and/CC of/IN procreating/VBG their/PRP$ kind/NN ?/. On/IN the/DT other/JJ hand/NN ,/, we/PRP may/MD feel/VB sure/JJ that/IN any/DT variation/NN in/IN the/DT least/JJS degree/NN injurious/JJ would/MD be/VB rigidly/RB destroyed/VBN ./. This/DT preservation/NN of/IN favourable/JJ individual/JJ differences/NNS and/CC variations/NNS ,/, and/CC the/DT destruction/NN of/IN those/DT which/WDT are/VBP injurious/JJ ,/, I/PRP have/VBP called/VBN Natural/NNP Selection/NN ,/, or/CC the/DT Survival/NNP of/IN the/DT Fittest/NNP ./. Variations/NNPS neither/DT useful/JJ nor/CC injurious/JJ would/MD not/RB be/VB affected/VBN by/IN natural/JJ selection/NN ,/, and/CC would/MD be/VB left/VBN either/DT a/DT fluctuating/VBG element/NN ,/, as/IN perhaps/RB we/PRP see/VB in/IN certain/JJ polymorphic/JJ species/NN ,/, or/CC would/MD ultimately/RB become/VB fixed/VBN ,/, owing/JJ to/TO the/DT nature/NN of/IN the/DT organism/NN and/CC the/DT nature/NN of/IN the/DT conditions/NNS ./. Several/JJ writers/NNS have/VBP misapprehended/VBN or/CC objected/VBD to/TO the/DT term/NN Natural/NNP Selection/NN ./. Some/DT have/VBP even/RB imagined/VBN that/IN natural/JJ selection/NN induces/VBZ variability/NN ,/, whereas/IN it/PRP implies/VBZ only/RB the/DT preservation/NN of/IN such/JJ variations/NNS as/IN arise/VB and/CC are/VBP beneficial/JJ to/TO the/DT being/VBG under/IN its/PRP$ conditions/NNS of/IN life/NN ./. No/DT one/CD objects/NNS to/TO agriculturists/NNS speaking/VBG of/IN the/DT potent/JJ effects/NNS of/IN man's/NNS selection/NN ;/: and/CC in/IN this/DT case/NN the/DT individual/JJ differences/NNS given/VBN by/IN nature/NN ,/, which/WDT man/NN for/IN some/DT object/NN selects/VBZ ,/, must/MD of/IN necessity/NN first/JJ occur/VB ./. Others/NNS have/VBP objected/VBD that/IN the/DT term/NN selection/NN implies/VBZ conscious/JJ choice/NN in/IN the/DT animals/NNS which/WDT become/VB modified/VBN ;/: and/CC it/PRP has/VBZ even/RB been/VBN urged/VBD that/IN ,/, as/IN plants/NNS have/VBP no/DT volition/NN ,/, natural/JJ selection/NN is/VBZ not/RB applicable/JJ to/TO them!/NN In/IN the/DT literal/JJ sense/NN of/IN the/DT word/NN ,/, no/DT doubt/NN ,/, natural/JJ selection/NN is/VBZ a/DT false/JJ term/NN ;/: but/CC who/WP ever/RB objected/VBD to/TO chemists/NNS speaking/VBG of/IN the/DT elective/JJ affinities/NNS of/IN the/DT various/JJ elements/NNS ?/. and/CC yet/RB an/DT acid/NN cannot/MD strictly/RB be/VB said/VBD to/TO elect/VB the/DT base/NN with/IN which/WDT it/PRP in/IN preference/NN combines/VBZ ./. It/PRP has/VBZ been/VBN said/VBD that/IN I/PRP speak/VB of/IN natural/JJ selection/NN as/IN an/DT active/JJ power/NN or/CC Deity/NN ;/: but/CC who/WP objects/NNS to/TO an/DT author/NN speaking/VBG of/IN the/DT attraction/NN of/IN gravity/NN as/IN ruling/NN the/DT movements/NNS of/IN the/DT planets/NNS ?/. Every/DT one/CD knows/VBZ what/WP is/VBZ meant/VBN and/CC is/VBZ implied/VBN by/IN such/JJ metaphorical/JJ expressions/NNS ;/: and/CC they/PRP are/VBP almost/RB necessary/JJ for/IN brevity/NN ./. So/RB again/RB it/PRP is/VBZ difficult/JJ to/TO avoid/VB personifying/VBG the/DT word/NN Nature/NNP ;/: but/CC I/PRP mean/VB by/IN Nature/NNP ,/, only/RB the/DT aggregate/JJ action/NN and/CC product/NN of/IN many/JJ natural/JJ laws/NNS ,/, and/CC by/IN laws/NNS the/DT sequence/NN of/IN events/NNS as/IN ascertained/VBN by/IN us/PRP ./. With/IN a/DT little/JJ familiarity/NN such/JJ superficial/JJ objections/NNS will/MD be/VB forgotten/VBN ./. We/PRP shall/MD best/JJS understand/VB the/DT probable/JJ course/NN of/IN natural/JJ selection/NN by/IN taking/VBG the/DT case/NN of/IN a/DT country/NN undergoing/VBG some/DT slight/JJ physical/JJ change/NN ,/, for/IN instance/NN ,/, of/IN climate/NN ./. The/DT proportional/JJ numbers/NNS of/IN its/PRP$ inhabitants/NNS will/MD almost/RB immediately/RB undergo/VB a/DT change/NN ,/, and/CC some/DT species/NN will/MD probably/RB become/VB extinct/JJ ./. We/PRP may/MD conclude/VB ,/, from/IN what/WP we/PRP have/VBP seen/VBN of/IN the/DT intimate/JJ and/CC complex/JJ manner/NN in/IN which/WDT the/DT inhabitants/NNS of/IN each/DT country/NN are/VBP bound/VBN together/RB ,/, that/IN any/DT change/NN in/IN the/DT numerical/JJ proportions/NNS of/IN the/DT inhabitants/NNS ,/, independently/RB of/IN the/DT change/NN of/IN climate/NN itself/PRP ,/, would/MD seriously/RB affect/VB the/DT others/NNS ./. If/IN the/DT country/NN were/VBD open/JJ on/IN its/PRP$ borders/NNS ,/, new/JJ forms/NNS would/MD certainly/RB immigrate/VB ,/, and/CC this/DT would/MD likewise/RB seriously/RB disturb/VB the/DT relations/NNS of/IN some/DT of/IN the/DT former/JJ inhabitants/NNS ./. let/VB it/PRP be/VB remembered/VBD how/WRB powerful/JJ the/DT influence/NN of/IN a/DT single/JJ introduced/VBN tree/NN or/CC mammal/NN has/VBZ been/VBN shown/VBN to/TO be/VB ./. But/CC in/IN the/DT case/NN of/IN an/DT island/NN ,/, or/CC of/IN a/DT country/NN partly/RB surrounded/VBN by/IN barriers/NNS ,/, into/IN which/WDT new/JJ and/CC better/JJR adapted/VBN forms/NNS could/MD not/RB freely/RB enter/VB ,/, we/PRP should/MD then/RB have/VBP places/NNS in/IN the/DT economy/NN of/IN nature/NN which/WDT would/MD assuredly/RB be/VB better/JJR filled/VBN up/IN ,/, if/IN some/DT of/IN the/DT original/JJ inhabitants/NNS were/VBD in/IN some/DT manner/NN modified/VBN ;/: for/IN ,/, had/VBD the/DT area/NN been/VBN open/JJ to/TO immigration/NN ,/, these/DT same/JJ places/NNS would/MD have/VB been/VBN seized/VBN on/IN by/IN intruders/NNS ./. In/IN such/JJ cases/NNS ,/, slight/JJ modifications/NNS ,/, which/WDT in/IN any/DT way/NN favoured/VBN the/DT individuals/NNS of/IN any/DT species/NN ,/, by/IN better/JJR adapting/VBG them/PRP to/TO their/PRP$ altered/VBN conditions/NNS ,/, would/MD tend/VB to/TO be/VB preserved/VBN ;/: and/CC natural/JJ selection/NN would/MD have/VB free/JJ scope/NN for/IN the/DT work/NN of/IN improvement/NN ./. We/PRP have/VBP good/JJ reason/NN to/TO believe/VB ,/, as/IN shown/VBN in/IN the/DT first/JJ chapter/NN ,/, that/IN changes/NNS in/IN the/DT conditions/NNS of/IN life/NN give/VB a/DT tendency/NN to/TO increased/VBN variability/NN ;/: and/CC in/IN the/DT foregoing/NN cases/NNS the/DT conditions/NNS have/VBP changed/VBN ,/, and/CC this/DT would/MD manifestly/RB be/VB favourable/JJ to/TO natural/JJ selection/NN ,/, by/IN affording/VBG a/DT better/JJR chance/NN of/IN the/DT occurrence/NN of/IN profitable/JJ variations/NNS ./. Unless/IN such/JJ occur/VB ,/, natural/JJ selection/NN can/MD do/VB nothing/NN ./. Under/IN the/DT term/NN of/IN "/" variations/NNS ,/, "/" it/PRP must/MD never/RB be/VB forgotten/VBN that/IN mere/JJ individual/JJ differences/NNS are/VBP included/VBD ./. As/IN man/NN can/MD produce/VB a/DT great/JJ result/NN with/IN his/PRP$ domestic/JJ animals/NNS and/CC plants/NNS by/IN adding/VBG up/IN in/IN any/DT given/VBN direction/NN individual/JJ differences/NNS ,/, so/RB could/MD natural/JJ selection/NN ,/, but/CC far/RB more/JJR easily/RB from/IN having/VBG incomparably/RB longer/RB time/NN for/IN action/NN ./. Nor/CC do/VBP I/PRP believe/VBP that/IN any/DT great/JJ physical/JJ change/NN ,/, as/IN of/IN climate/NN ,/, or/CC any/DT unusual/JJ degree/NN of/IN isolation/NN to/TO check/NN immigration/NN ,/, is/VBZ necessary/JJ in/IN order/NN that/IN new/JJ and/CC unoccupied/JJ places/NNS should/MD be/VB left/VBN ,/, for/IN natural/JJ selection/NN to/TO fill/VB up/IN by/IN improving/VBG some/DT of/IN the/DT varying/VBG inhabitants/NNS ./. 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As/IN man/NN can/MD produce/VB ,/, and/CC certainly/RB has/VBZ produced/VBN ,/, a/DT great/JJ result/NN by/IN his/PRP$ methodical/JJ and/CC unconscious/JJ means/VBZ of/IN selection/NN ,/, what/WP may/MD not/RB natural/JJ selection/NN effect/NN ?/. Man/NN can/MD act/NN only/RB on/IN external/JJ and/CC visible/JJ characters/NNS :/: Nature/NNP ,/, if/IN I/PRP may/MD be/VB allowed/VBN to/TO personify/VB the/DT natural/JJ preservation/NN or/CC survival/NN of/IN the/DT fittest/JJS ,/, cares/VBZ nothing/NN for/IN appearances/NNS ,/, except/IN in/IN so/RB far/RB as/IN they/PRP are/VBP useful/JJ to/TO any/DT being/VBG ./. She/PRP can/MD act/NN on/IN every/DT internal/JJ organ/NN ,/, on/IN every/DT shade/NN of/IN constitutional/JJ difference/NN ,/, on/IN the/DT whole/JJ machinery/NN of/IN life/NN ./. Man/NN selects/VBZ only/RB for/IN his/PRP$ own/JJ good/JJ :/: Nature/NNP only/RB for/IN that/IN of/IN the/DT being/VBG which/WDT she/PRP tends/VBZ ./. 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It/PRP may/MD metaphorically/RB be/VB said/VBD that/IN natural/JJ selection/NN is/VBZ daily/JJ and/CC hourly/JJ scrutinising/VBG ,/, throughout/IN the/DT world/NN ,/, the/DT slightest/JJS variations/NNS ;/: rejecting/VBG those/DT that/IN are/VBP bad/JJ ,/, preserving/VBG and/CC adding/VBG up/IN all/DT that/IN are/VBP good/JJ ;/: silently/RB and/CC insensibly/RB working/VBG ,/, whenever/WRB and/CC wherever/WRB opportunity/NN offers/VBZ ,/, at/IN the/DT improvement/NN of/IN each/DT organic/JJ being/VBG in/IN relation/NN to/TO its/PRP$ organic/JJ and/CC inorganic/JJ conditions/NNS of/IN life/NN ./. We/PRP see/VB nothing/NN of/IN these/DT slow/JJ changes/NNS in/IN progress/NN ,/, until/IN the/DT hand/NN of/IN time/NN has/VBZ marked/VBN the/DT lapse/NN of/IN ages/NNS ,/, and/CC then/RB so/RB imperfect/JJ is/VBZ our/PRP$ view/NN into/IN long/JJ past/JJ geological/JJ ages/NNS ,/, that/IN we/PRP see/VB only/RB that/IN the/DT forms/NNS of/IN life/NN are/VBP now/RB different/JJ from/IN what/WP they/PRP formerly/RB were/VBD ./. In/IN order/NN that/IN any/DT great/JJ amount/NN of/IN modification/NN should/MD be/VB effected/VBN in/IN a/DT species/NN ,/, a/DT variety/NN when/WRB once/RB formed/VBN must/MD again/RB ,/, perhaps/RB after/IN a/DT long/JJ interval/NN of/IN time/NN ,/, vary/VBP or/CC present/JJ individual/JJ differences/NNS of/IN the/DT same/JJ favourable/JJ nature/NN as/IN before/IN ;/: and/CC these/DT must/MD be/VB again/RB preserved/VBN ,/, and/CC so/RB onwards/RB step/NN by/IN step/NN ./. Seeing/VBG that/IN individual/JJ differences/NNS of/IN the/DT same/JJ kind/NN perpetually/RB recur/VB ,/, this/DT can/MD hardly/RB be/VB considered/VBN as/IN an/DT unwarrantable/JJ assumption/NN ./. But/CC whether/IN it/PRP is/VBZ true/JJ ,/, we/PRP can/MD judge/NN only/RB by/IN seeing/VBG how/WRB far/RB the/DT hypothesis/NN accords/NNS with/IN and/CC explains/VBZ the/DT general/JJ phenomena/NNS of/IN nature/NN ./. On/IN the/DT other/JJ hand/NN ,/, the/DT ordinary/JJ belief/NN that/IN the/DT amount/NN of/IN possible/JJ variation/NN is/VBZ a/DT strictly/RB limited/JJ quantity/NN is/VBZ likewise/RB a/DT simple/JJ assumption/NN ./. Although/IN natural/JJ selection/NN can/MD act/NN only/RB through/IN and/CC for/IN the/DT good/JJ of/IN each/DT being/VBG ,/, yet/RB characters/NNS and/CC structures/NNS ,/, which/WDT we/PRP are/VBP apt/JJ to/TO consider/VB as/IN of/IN very/RB trifling/JJ importance/NN ,/, may/MD thus/RB be/VB acted/VBD on/IN ./. When/WRB we/PRP see/VB leaf/NN eating/VBG insects/NNS green/JJ ,/, and/CC bark/NN feeders/NNS mottled/VBN grey/JJ ;/: the/DT alpine/NN ptarmigan/NN white/JJ in/IN winter/NN ,/, the/DT red/JJ grouse/VBP the/DT colour/NN of/IN heather/NN ,/, we/PRP must/MD believe/VB that/IN these/DT tints/NNS are/VBP of/IN service/NN to/TO these/DT birds/NNS and/CC insects/NNS in/IN preserving/VBG them/PRP from/IN danger/NN ./. Grouse/NNP ,/, if/IN not/RB destroyed/VBN at/IN some/DT period/NN of/IN their/PRP$ lives/NNS ,/, would/MD increase/NN in/IN countless/JJ numbers/NNS ;/: they/PRP are/VBP known/VBN to/TO suffer/VB largely/RB from/IN birds/NNS of/IN prey/NN ;/: and/CC hawks/NNS are/VBP guided/VBN by/IN eyesight/NN to/TO their/PRP$ prey/NN so/RB much/JJ so/RB ,/, that/IN on/IN parts/NNS of/IN the/DT Continent/NN persons/NNS are/VBP warned/VBD not/RB to/TO keep/VB white/JJ pigeons/NNS ,/, as/IN being/VBG the/DT most/RBS liable/JJ to/TO destruction/NN ./. Hence/RB natural/JJ selection/NN might/MD be/VB effective/JJ in/IN giving/VBG the/DT proper/JJ colour/NN to/TO each/DT kind/NN of/IN grouse/VBP ,/, and/CC in/IN keeping/VBG that/IN colour/NN ,/, when/WRB once/RB acquired/VBN ,/, true/JJ and/CC constant/JJ ./. Nor/CC ought/MD we/PRP to/TO think/VB that/IN the/DT occasional/JJ destruction/NN of/IN an/DT animal/NN of/IN any/DT particular/JJ colour/NN would/MD produce/VB little/JJ effect/NN :/: we/PRP should/MD remember/VB how/WRB essential/JJ it/PRP is/VBZ in/IN a/DT flock/NN of/IN white/JJ sheep/NN to/TO destroy/VB a/DT lamb/NN with/IN the/DT faintest/JJS trace/NN of/IN black/JJ ./. We/PRP have/VBP seen/VBN how/WRB the/DT colour/NN of/IN the/DT hogs/NNS ,/, which/WDT feed/NN on/IN the/DT "/" paint/NN root/NN "/" in/IN Virginia/NNP ,/, determines/VBZ whether/IN they/PRP shall/MD live/VB or/CC die/VB ./. In/IN plants/NNS ,/, the/DT down/RB on/IN the/DT fruit/NN and/CC the/DT colour/NN of/IN the/DT flesh/NN are/VBP considered/VBN by/IN botanists/NNS as/IN characters/NNS of/IN the/DT most/RBS trifling/JJ importance/NN :/: yet/RB we/PRP hear/VB from/IN an/DT excellent/JJ horticulturist/NN ,/, Downing/NNP ,/, that/IN in/IN the/DT United/NNP States/NNPS ,/, smooth/JJ skinned/VBN fruits/NNS suffer/VB far/RB more/JJR from/IN a/DT beetle/NN ,/, a/DT Curculio/NNP ,/, than/IN those/DT with/IN down/RB ;/: that/IN purple/JJ plums/NNS suffer/VB far/RB more/JJR from/IN a/DT certain/JJ disease/NN than/IN yellow/JJ plums/NNS ;/: whereas/IN another/DT disease/NN attacks/NNS yellow/JJ fleshed/VBN peaches/NNS far/RB more/JJR than/IN those/DT with/IN other/JJ coloured/JJ flesh/NN ./. 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It/PRP is/VBZ also/RB necessary/JJ to/TO bear/VB in/IN mind/NN that/IN ,/, owing/JJ to/TO the/DT law/NN of/IN correlation/NN ,/, when/WRB one/CD part/NN varies/VBZ ,/, and/CC the/DT variations/NNS are/VBP accumulated/VBN through/IN natural/JJ selection/NN ,/, other/JJ modifications/NNS ,/, often/RB of/IN the/DT most/RBS unexpected/JJ nature/NN ,/, will/MD ensue/VB ./. As/IN we/PRP see/VB that/IN those/DT variations/NNS which/WDT ,/, under/IN domestication/NN ,/, appear/VB at/IN any/DT particular/JJ period/NN of/IN life/NN ,/, tend/VBP to/TO reappear/VB in/IN the/DT offspring/NN at/IN the/DT same/JJ period/NN ;/: for/IN instance/NN ,/, in/IN the/DT shape/NN ,/, size/NN ,/, and/CC flavour/NN of/IN the/DT seeds/NNS of/IN the/DT many/JJ varieties/NNS of/IN our/PRP$ culinary/JJ and/CC agricultural/JJ plants/NNS ;/: in/IN the/DT caterpillar/NN and/CC cocoon/NN stages/NNS of/IN the/DT varieties/NNS of/IN the/DT silk/NN worm/NN ;/: in/IN the/DT eggs/NNS of/IN poultry/NN ,/, and/CC in/IN the/DT colour/NN of/IN the/DT down/RB of/IN their/PRP$ chickens/NNS ;/: in/IN the/DT horns/NNS of/IN our/PRP$ sheep/NN and/CC cattle/NNS when/WRB nearly/RB adult/NN ;/: so/RB in/IN a/DT state/NN of/IN nature/NN natural/JJ selection/NN will/MD be/VB enabled/VBD to/TO act/NN on/IN and/CC modify/VB organic/JJ beings/NNS at/IN any/DT age/NN ,/, by/IN the/DT accumulation/NN of/IN variations/NNS profitable/JJ at/IN that/IN age/NN ,/, and/CC by/IN their/PRP$ inheritance/NN at/IN a/DT corresponding/JJ age/NN ./. If/IN it/PRP profit/NN a/DT plant/NN to/TO have/VB its/PRP$ seeds/NNS more/JJR and/CC more/JJR widely/RB disseminated/VBN by/IN the/DT wind/NN ,/, I/PRP can/MD see/VB no/DT greater/JJR difficulty/NN in/IN this/DT being/VBG effected/VBN through/IN natural/JJ selection/NN ,/, than/IN in/IN the/DT cotton/NN planter/NN increasing/VBG and/CC improving/VBG by/IN selection/NN the/DT down/RB in/IN the/DT pods/NNS on/IN his/PRP$ cotton/NN trees/NNS ./. Natural/NNP selection/NN may/MD modify/VB and/CC adapt/VB the/DT larva/NN of/IN an/DT insect/NN to/TO a/DT score/NN of/IN contingencies/NNS ,/, wholly/RB different/JJ from/IN those/DT which/WDT concern/NN the/DT mature/JJ insect/NN ;/: and/CC these/DT modifications/NNS may/MD affect/VB ,/, through/IN correlation/NN ,/, the/DT structure/NN of/IN the/DT adult/NN ./. So/RB ,/, conversely/RB ,/, modifications/NNS in/IN the/DT adult/NN may/MD affect/VB the/DT structure/NN of/IN the/DT larva/NN ;/: but/CC in/IN all/DT cases/NNS natural/JJ selection/NN will/MD ensure/VB that/IN they/PRP shall/MD not/RB be/VB injurious/JJ :/: for/IN if/IN they/PRP were/VBD so/RB ,/, the/DT species/NN would/MD become/VB extinct/JJ ./. Natural/NNP selection/NN will/MD modify/VB the/DT structure/NN of/IN the/DT young/JJ in/IN relation/NN to/TO the/DT parent/NN ,/, and/CC of/IN the/DT parent/NN in/IN relation/NN to/TO the/DT young/JJ ./. In/IN social/JJ animals/NNS it/PRP will/MD adapt/VB the/DT structure/NN of/IN each/DT individual/JJ for/IN the/DT benefit/NN of/IN the/DT whole/JJ community/NN ,/, if/IN the/DT community/NN profits/NNS by/IN the/DT selected/VBN change/NN ./. What/WP natural/JJ selection/NN cannot/MD do/VB ,/, is/VBZ to/TO modify/VB the/DT structure/NN of/IN one/CD species/NN ,/, without/IN giving/VBG it/PRP any/DT advantage/NN ,/, for/IN the/DT good/JJ Of/IN another/DT species/NN ;/: and/CC though/IN statements/NNS to/TO this/DT effect/NN may/MD be/VB found/VBD in/IN works/NNS of/IN natural/JJ history/NN ,/, I/PRP cannot/MD find/VB one/CD case/NN which/WDT will/MD bear/VB investigation/NN ./. A/DT structure/NN used/VBN only/RB once/RB in/IN an/DT animal's/NNS life/NN ,/, if/IN of/IN high/JJ importance/NN to/TO it/PRP ,/, might/MD be/VB modified/VBN to/TO any/DT extent/NN by/IN natural/JJ selection/NN ;/: for/IN instance/NN ,/, the/DT great/JJ jaws/NNS possessed/VBD by/IN certain/JJ insects/NNS ,/, used/VBN exclusively/RB for/IN opening/NN the/DT cocoon/NN or/CC the/DT hard/JJ tip/NN to/TO the/DT beak/NN of/IN unhatched/JJ birds/NNS ,/, used/VBN for/IN breaking/VBG the/DT egg/NN ./. It/PRP has/VBZ been/VBN asserted/VBD ,/, that/IN of/IN the/DT best/JJS short/JJ beaked/VBD tumbler/NN pigeons/NNS a/DT greater/JJR number/NN perish/VB in/IN the/DT egg/NN than/IN are/VBP able/JJ to/TO get/VB out/IN of/IN it/PRP ;/: so/RB that/IN fanciers/NNS assist/VB in/IN the/DT act/NN of/IN hatching/NN ./. Now/RB if/IN nature/NN had/VBD to/TO make/VB the/DT beak/NN of/IN a/DT full/JJ grown/VBN pigeon/NN very/RB short/JJ for/IN the/DT bird's/NNS own/JJ advantage/NN ,/, the/DT process/NN of/IN modification/NN would/MD be/VB very/RB slow/JJ ,/, and/CC there/EX would/MD be/VB simultaneously/RB the/DT most/RBS rigorous/JJ selection/NN of/IN all/DT the/DT young/JJ birds/NNS within/IN the/DT egg/NN ,/, which/WDT had/VBD the/DT most/RBS powerful/JJ and/CC hardest/JJS beaks/NNS ,/, for/IN all/DT with/IN weak/JJ beaks/NNS would/MD inevitably/RB perish/VB ;/: or/CC ,/, more/JJR delicate/JJ and/CC more/JJR easily/RB broken/VBN shells/NNS might/MD be/VB selected/VBN ,/, the/DT thickness/NN of/IN the/DT shell/NN being/VBG known/VBN to/TO vary/VB like/IN every/DT other/JJ structure/NN ./. It/PRP may/MD be/VB well/RB here/RB to/TO remark/NN that/IN with/IN all/DT beings/NNS there/EX must/MD be/VB much/JJ fortuitous/JJ destruction/NN ,/, which/WDT can/MD have/VB little/JJ or/CC no/DT influence/NN on/IN the/DT course/NN of/IN natural/JJ selection/NN ./. For/IN instance/NN a/DT vast/JJ number/NN of/IN eggs/NNS or/CC seeds/NNS are/VBP annually/RB devoured/VBN ,/, and/CC these/DT could/MD be/VB modified/VBN through/IN natural/JJ selection/NN only/RB if/IN they/PRP varied/VBN in/IN some/DT manner/NN which/WDT protected/VBN them/PRP from/IN their/PRP$ enemies/NNS ./. Yet/RB many/JJ of/IN these/DT eggs/NNS or/CC seeds/NNS would/MD perhaps/RB ,/, if/IN not/RB destroyed/VBN ,/, have/VBP yielded/VBD individuals/NNS better/JJR adapted/VBN to/TO their/PRP$ conditions/NNS of/IN life/NN than/IN any/DT of/IN these/DT which/WDT happened/VBD to/TO survive/VB ./. So/RB again/RB a/DT vast/JJ number/NN of/IN mature/JJ animals/NNS and/CC plants/NNS ,/, whether/IN or/CC not/RB they/PRP be/VB the/DT best/JJS adapted/VBN to/TO their/PRP$ conditions/NNS ,/, must/MD be/VB annually/RB destroyed/VBN by/IN accidental/JJ causes/NNS ,/, which/WDT would/MD not/RB be/VB in/IN the/DT least/JJS degree/NN mitigated/VBN by/IN certain/JJ changes/NNS of/IN structure/NN or/CC constitution/NN which/WDT would/MD in/IN other/JJ ways/NNS be/VB beneficial/JJ to/TO the/DT species/NN ./. But/CC let/VB the/DT destruction/NN of/IN the/DT adults/NNS be/VB ever/RB so/RB heavy/JJ ,/, if/IN the/DT number/NN which/WDT can/MD exist/VB in/IN any/DT district/NN be/VB not/RB wholly/RB kept/VBD down/RB by/IN such/JJ causes/NNS ,/, or/CC again/RB let/VB the/DT destruction/NN of/IN eggs/NNS or/CC seeds/NNS be/VB so/RB great/JJ that/IN only/RB a/DT hundredth/JJ or/CC a/DT thousandth/JJ part/NN are/VBP developed/VBN ,/, yet/RB of/IN those/DT which/WDT do/VBP survive/VB ,/, the/DT best/JJS adapted/VBN individuals/NNS ,/, supposing/VBG that/IN there/EX is/VBZ any/DT variability/NN in/IN favourable/JJ direction/NN ,/, will/MD tend/VB to/TO propagate/VB their/PRP$ kind/NN in/IN larger/JJR numbers/NNS than/IN the/DT less/JJR well/RB adapted/VBN ./. If/IN the/DT numbers/NNS be/VB wholly/RB kept/VBD down/RB by/IN the/DT causes/NNS just/RB indicated/VBD ,/, as/IN will/MD often/RB have/VBP been/VBN the/DT case/NN ,/, natural/JJ selection/NN will/MD be/VB powerless/JJ in/IN certain/JJ beneficial/JJ directions/NNS ;/: but/CC this/DT is/VBZ no/DT valid/JJ objection/NN to/TO its/PRP$ efficiency/NN at/IN other/JJ times/NNS and/CC in/IN other/JJ ways/NNS ;/: for/IN we/PRP are/VBP far/RB from/IN having/VBG any/DT reason/NN to/TO suppose/VB that/IN many/JJ species/NN ever/RB undergo/VB modification/NN and/CC improvement/NN at/IN the/DT same/JJ time/NN in/IN the/DT same/JJ area/NN ./. Sexual/NNP Selection/NN Inasmuch/RB as/IN peculiarities/NNS often/RB appear/VB under/IN domestication/NN in/IN one/CD sex/NN and/CC become/VB hereditarily/RB attached/VBN to/TO that/IN sex/NN ,/, so/RB no/DT doubt/NN it/PRP will/MD be/VB under/IN nature/NN ./. Thus/RB it/PRP is/VBZ rendered/VBN possible/JJ for/IN the/DT two/CD sexes/NNS to/TO be/VB modified/VBN through/IN natural/JJ selection/NN in/IN relation/NN to/TO different/JJ habits/NNS of/IN life/NN ,/, as/IN is/VBZ sometimes/RB the/DT case/NN ;/: or/CC for/IN one/CD sex/NN to/TO be/VB modified/VBN in/IN relation/NN to/TO the/DT other/JJ sex/NN ,/, as/IN commonly/RB occurs/VBZ ./. This/DT leads/VBZ me/PRP to/TO say/VB a/DT few/JJ words/NNS on/IN what/WP I/PRP have/VBP called/VBN Sexual/NNP Selection/NN ./. This/DT form/NN of/IN selection/NN depends/VBZ ,/, not/RB on/IN a/DT struggle/NN for/IN existence/NN in/IN relation/NN to/TO other/JJ organic/JJ beings/NNS or/CC to/TO external/JJ conditions/NNS ,/, but/CC on/IN a/DT struggle/NN between/IN the/DT individuals/NNS of/IN one/CD sex/NN ,/, generally/RB the/DT males/NNS ,/, for/IN the/DT possession/NN of/IN the/DT other/JJ sex/NN ./. The/DT result/NN is/VBZ not/RB death/NN to/TO the/DT unsuccessful/JJ competitor/NN ,/, but/CC few/JJ or/CC no/DT offspring/NN ./. Sexual/NNP selection/NN is/VBZ ,/, therefore/RB ,/, less/JJR rigorous/JJ than/IN natural/JJ selection/NN ./. Generally/RB ,/, the/DT most/RBS vigorous/JJ males/NNS ,/, those/DT which/WDT are/VBP best/JJS fitted/VBN for/IN their/PRP$ places/NNS in/IN nature/NN ,/, will/MD leave/VB most/RBS progeny/NN ./. But/CC in/IN many/JJ cases/NNS ,/, victory/NN depends/VBZ not/RB so/RB much/JJ on/IN general/JJ vigor/NN ,/, as/IN on/IN having/VBG special/JJ weapons/NNS ,/, confined/VBN to/TO the/DT male/JJ sex/NN ./. A/DT hornless/JJ stag/NN or/CC spurless/JJ cock/NN would/MD have/VB a/DT poor/JJ chance/NN of/IN leaving/VBG numerous/JJ offspring/NN ./. Sexual/NNP selection/NN ,/, by/IN always/RB allowing/VBG the/DT victor/NN to/TO breed/NN ,/, might/MD surely/RB give/VB indomitable/JJ courage/NN ,/, length/NN to/TO the/DT spur/VB ,/, and/CC strength/NN to/TO the/DT wing/NN to/TO strike/NN in/IN the/DT spurred/VBN leg/NN ,/, in/IN nearly/RB the/DT same/JJ manner/NN as/IN does/VBZ the/DT brutal/JJ cockfighter/NN by/IN the/DT careful/JJ selection/NN of/IN his/PRP$ best/JJS cocks/NNS ./. How/WRB low/JJ in/IN the/DT scale/NN of/IN nature/NN the/DT law/NN of/IN battle/NN descends/VBZ ,/, I/PRP know/VB not/RB ;/: male/JJ alligators/NNS have/VBP been/VBN described/VBN as/IN fighting/VBG ,/, bellowing/VBG ,/, and/CC whirling/VBG round/NN ,/, like/IN Indians/NNPS in/IN a/DT war/NN dance/NN ,/, for/IN the/DT possession/NN of/IN the/DT females/NNS ;/: male/JJ salmons/NNS have/VBP been/VBN observed/VBN fighting/VBG all/DT day/NN long/JJ ;/: male/JJ stagbeetles/NNS sometimes/RB bear/VB wounds/NNS from/IN the/DT huge/JJ mandibles/NNS of/IN other/JJ males/NNS ;/: the/DT males/NNS of/IN certain/JJ hymenopterous/JJ insects/NNS have/VBP been/VBN frequently/RB seen/VBN by/IN that/IN inimitable/JJ observer/NN M/NNP ./. Fabre/NNP ,/, fighting/VBG for/IN a/DT particular/JJ female/JJ who/WP sits/VBZ by/IN ,/, an/DT apparently/RB unconcerned/JJ beholder/NN of/IN the/DT struggle/NN ,/, and/CC then/RB retires/VBZ with/IN the/DT conqueror/NN ./. 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All/DT those/DT who/WP have/VBP attended/VBD to/TO the/DT subject/NN ,/, believe/VBP that/IN there/EX is/VBZ the/DT severest/JJS rivalry/NN between/IN the/DT males/NNS of/IN many/JJ species/NN to/TO attract/VB ,/, by/IN singing/VBG ,/, the/DT females/NNS ./. The/DT rock/NN thrush/NN of/IN Guiana/NNP ,/, birds/NNS of/IN paradise/NN ,/, and/CC some/DT others/NNS ,/, congregate/VB ;/: and/CC successive/JJ males/NNS display/NN with/IN the/DT most/RBS elaborate/VB care/NN ,/, and/CC show/NN off/IN in/IN the/DT best/JJS manner/NN ,/, their/PRP$ gorgeous/JJ plumage/NN ;/: they/PRP likewise/RB perform/VB strange/JJ antics/NNS before/IN the/DT females/NNS ,/, which/WDT ,/, standing/VBG by/IN as/IN spectators/NNS ,/, at/IN last/JJ choose/VB the/DT most/RBS attractive/JJ partner/NN ./. Those/DT who/WP have/VBP closely/RB attended/VBD to/TO birds/NNS in/IN confinement/NN well/RB know/VB that/IN they/PRP often/RB take/VB individual/JJ preferences/NNS and/CC dislikes/VBZ :/: thus/RB Sir/NNP R/NN ./. Heron/NNP has/VBZ described/VBN how/WRB a/DT pied/VBN peacock/NN was/VBD eminently/RB attractive/JJ to/TO all/DT his/PRP$ hen/NN birds/NNS ./. I/PRP cannot/MD here/RB enter/VB on/IN the/DT necessary/JJ details/NNS ;/: but/CC if/IN man/NN can/MD in/IN a/DT short/JJ time/NN give/VB beauty/NN and/CC an/DT elegant/JJ carriage/NN to/TO his/PRP$ bantams/NNS ,/, according/VBG to/TO his/PRP$ standard/JJ of/IN beauty/NN ,/, I/PRP can/MD see/VB no/DT good/JJ reason/NN to/TO doubt/NN that/IN female/JJ birds/NNS ,/, by/IN selecting/VBG ,/, during/IN thousands/NNS of/IN generations/NNS ,/, the/DT most/RBS melodious/JJ or/CC beautiful/JJ males/NNS ,/, according/VBG to/TO their/PRP$ standard/JJ of/IN beauty/NN ,/, might/MD produce/VB a/DT marked/VBN effect/NN ./. 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Thus/RB it/PRP is/VBZ ,/, as/IN I/PRP believe/VBP ,/, that/IN when/WRB the/DT males/NNS and/CC females/NNS of/IN any/DT animal/NN have/VBP the/DT same/JJ general/JJ habits/NNS of/IN life/NN ,/, but/CC differ/VBP in/IN structure/NN ,/, colour/NN ,/, or/CC ornament/NN ,/, such/JJ differences/NNS have/VBP been/VBN mainly/RB caused/VBN by/IN sexual/JJ selection/NN :/: that/IN is/VBZ ,/, by/IN individual/JJ males/NNS having/VBG had/VBD ,/, in/IN successive/JJ generations/NNS ,/, some/DT slight/JJ advantage/NN over/IN other/JJ males/NNS ,/, in/IN their/PRP$ weapons/NNS ,/, means/VBZ of/IN defence/NN ,/, or/CC charms/NNS ,/, which/WDT they/PRP have/VBP transmitted/VBN to/TO their/PRP$ male/JJ offspring/NN alone/RB ./. Yet/RB ,/, I/PRP would/MD not/RB wish/VBP to/TO attribute/VB all/DT sexual/JJ differences/NNS to/TO this/DT agency/NN :/: for/IN we/PRP see/VB in/IN our/PRP$ domestic/JJ animals/NNS peculiarities/NNS arising/VBG and/CC becoming/VBG attached/VBN to/TO the/DT male/JJ sex/NN ,/, which/WDT apparently/RB have/VBP not/RB been/VBN augmented/VBN through/IN selection/NN by/IN man/NN ./. The/DT tuft/NN of/IN hair/NN on/IN the/DT breast/NN of/IN the/DT wild/JJ turkey/NN cock/NN cannot/MD be/VB of/IN any/DT use/NN ,/, and/CC it/PRP is/VBZ doubtful/JJ whether/IN it/PRP can/MD be/VB ornamental/JJ in/IN the/DT eyes/NNS of/IN the/DT female/JJ bird/NN ;/: indeed/RB ,/, had/VBD the/DT tuft/NN appeared/VBD under/IN domestication/NN ,/, it/PRP would/MD have/VB been/VBN called/VBN a/DT monstrosity/NN ./. 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Isolation/NNP ,/, also/RB ,/, is/VBZ an/DT important/JJ element/NN in/IN the/DT modification/NN of/IN species/NN through/IN natural/JJ selection/NN ./. In/IN a/DT confined/VBN or/CC isolated/VBN area/NN ,/, if/IN not/RB very/RB large/JJ ,/, the/DT organic/JJ and/CC inorganic/JJ conditions/NNS of/IN life/NN will/MD generally/RB be/VB almost/RB uniform/NN ;/: so/RB that/IN natural/JJ selection/NN will/MD tend/VB to/TO modify/VB all/DT the/DT varying/VBG individuals/NNS of/IN the/DT same/JJ species/NN in/IN the/DT same/JJ manner/NN ./. Intercrossing/VBG with/IN the/DT inhabitants/NNS of/IN the/DT surrounding/VBG districts/NNS will/MD ,/, also/RB ,/, be/VB thus/RB prevented/VBN ./. Moritz/NNP Wagner/NNP has/VBZ lately/RB published/VBN an/DT interesting/JJ essay/NN on/IN this/DT subject/NN ,/, and/CC has/VBZ shown/VBN that/IN the/DT service/NN rendered/VBN by/IN isolation/NN in/IN preventing/VBG crosses/VBZ between/IN newly/RB formed/VBN varieties/NNS is/VBZ probably/RB greater/JJR even/RB than/IN I/PRP supposed/VBN ./. But/CC from/IN reasons/NNS already/RB assigned/VBN I/PRP can/MD by/IN no/DT means/VBZ agree/VB with/IN this/DT naturalist/NN ,/, that/IN migration/NN and/CC isolation/NN are/VBP necessary/JJ elements/NNS for/IN the/DT formation/NN of/IN new/JJ species/NN ./. 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If/IN ,/, however/RB ,/, an/DT isolated/VBN area/NN be/VB very/RB small/JJ ,/, either/DT from/IN being/VBG surrounded/VBN by/IN barriers/NNS ,/, or/CC from/IN having/VBG very/RB peculiar/JJ physical/JJ conditions/NNS ,/, the/DT total/JJ number/NN of/IN the/DT inhabitants/NNS will/MD be/VB small/JJ ;/: and/CC this/DT will/MD retard/VB the/DT production/NN of/IN new/JJ species/NN through/IN natural/JJ selection/NN ,/, by/IN decreasing/VBG the/DT chances/NNS of/IN favourable/JJ variations/NNS arising/VBG ./. The/DT mere/JJ lapse/NN of/IN time/NN by/IN itself/PRP does/VBZ nothing/NN ,/, either/DT for/IN or/CC against/IN natural/JJ selection/NN ./. 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In/IN accordance/NN with/IN this/DT view/NN ,/, we/PRP can/MD ,/, perhaps/RB ,/, understand/VB some/DT facts/NNS which/WDT will/MD be/VB again/RB alluded/VBD to/TO in/IN our/PRP$ chapter/NN on/IN Geographical/JJ Distribution/NNP ;/: for/IN instance/NN ,/, the/DT fact/NN of/IN the/DT productions/NNS of/IN the/DT smaller/JJR continent/NN of/IN Australia/NNP now/RB yielding/VBG before/IN those/DT of/IN the/DT larger/JJR Europaeo/NNP Asiatic/JJ area/NN ./. Thus/RB ,/, also/RB ,/, it/PRP is/VBZ that/IN continental/JJ productions/NNS have/VBP everywhere/RB become/VB so/RB largely/RB naturalised/VBN on/IN islands/NNS ./. On/IN a/DT small/JJ island/NN ,/, the/DT race/NN for/IN life/NN will/MD have/VB been/VBN less/JJR severe/JJ ,/, and/CC there/EX will/MD have/VB been/VBN less/JJR modification/NN and/CC less/JJR extermination/NN ./. 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As/IN frequent/JJ inflammation/NN of/IN the/DT eyes/NNS must/MD be/VB injurious/JJ to/TO any/DT animal/NN ,/, and/CC as/IN eyes/NNS are/VBP certainly/RB not/RB necessary/JJ to/TO animals/NNS having/VBG subterranean/JJ habits/NNS ,/, a/DT reduction/NN in/IN their/PRP$ size/NN ,/, with/IN the/DT adhesion/NN of/IN the/DT eyelids/NNS and/CC growth/NN of/IN fur/NN over/IN them/PRP ,/, might/MD in/IN such/JJ case/NN be/VB an/DT advantage/NN ;/: and/CC if/IN so/RB ,/, natural/JJ selection/NN would/MD aid/NN the/DT effects/NNS of/IN disuse/NN ./. It/PRP is/VBZ well/RB known/VBN that/IN several/JJ animals/NNS ,/, belonging/VBG to/TO the/DT most/RBS different/JJ classes/NNS ,/, which/WDT inhabit/VBP the/DT caves/NNS of/IN Carniola/NNP and/CC of/IN Kentucky/NNP ,/, are/VBP blind/JJ ./. in/IN some/DT of/IN the/DT crabs/NNS the/DT foot/NN stalk/VBP for/IN the/DT eye/NN remains/VBZ ,/, though/IN the/DT eye/NN is/VBZ gone/VBN ;/: the/DT stand/VB for/IN the/DT telescope/NN is/VBZ there/EX ,/, though/IN the/DT telescope/NN with/IN its/PRP$ glasses/NNS has/VBZ been/VBN lost/VBD ./. As/IN it/PRP is/VBZ difficult/JJ to/TO imagine/VB that/IN eyes/NNS ,/, though/IN useless/JJ ,/, could/MD be/VB in/IN any/DT way/NN injurious/JJ to/TO animals/NNS living/VBG in/IN darkness/NN ,/, their/PRP$ loss/NN may/MD be/VB attributed/VBD to/TO disuse/NN ./. In/IN one/CD of/IN the/DT blind/JJ animals/NNS ,/, namely/RB ,/, the/DT cave/NN rat/NN (/( Noetoma/NNP )/SYM ,/, two/CD of/IN which/WDT were/VBD captured/VBN by/IN Professor/NNP Silliman/NNP at/IN above/IN half/NN a/DT mile/NN distance/NN from/IN the/DT mouth/NN of/IN the/DT cave/NN ,/, and/CC therefore/RB not/RB in/IN the/DT profoundest/JJS depths/NNS ,/, the/DT eyes/NNS were/VBD lustrous/JJ and/CC of/IN large/JJ size/NN ;/: and/CC these/DT animals/NNS ,/, as/IN I/PRP am/VBP informed/VBN by/IN Professor/NNP Silliman/NNP ,/, after/IN having/VBG been/VBN exposed/VBN for/IN about/IN a/DT month/NN to/TO a/DT graduated/VBN light/NN ,/, acquired/VBN a/DT dim/JJ perception/NN of/IN objects/NNS ./. It/PRP is/VBZ difficult/JJ to/TO imagine/VB conditions/NNS of/IN life/NN more/JJR similar/JJ than/IN deep/JJ limestone/NN caverns/NNS under/IN a/DT nearly/RB similar/JJ climate/NN ;/: so/RB that/IN ,/, in/IN accordance/NN with/IN the/DT old/JJ view/NN of/IN the/DT blind/JJ animals/NNS having/VBG been/VBN separately/RB created/VBN for/IN the/DT American/NNP and/CC European/JJ caverns/NNS ,/, very/RB close/VB similarity/NN in/IN their/PRP$ organisation/NN and/CC affinities/NNS might/MD have/VB been/VBN expected/VBN ./. This/DT is/VBZ certainly/RB not/RB the/DT case/NN if/IN we/PRP look/VB at/IN the/DT two/CD whole/JJ faunas/NNS ;/: and/CC with/IN respect/NN to/TO the/DT insects/NNS alone/RB ,/, Schiodte/NNP has/VBZ remarked/VBN ,/, "/" We/PRP are/VBP accordingly/RB prevented/VBN from/IN considering/VBG the/DT entire/JJ phenomenon/NN in/IN any/DT other/JJ light/NN than/IN something/NN purely/RB local/JJ ,/, and/CC the/DT similarity/NN which/WDT is/VBZ exhibited/VBN in/IN a/DT few/JJ forms/NNS between/IN the/DT Mammoth/NNP cave/NN (/( in/IN Kentucky/NNP )/SYM and/CC the/DT caves/NNS in/IN Carniola/NNP ,/, otherwise/RB than/IN as/IN a/DT very/RB plain/JJ expression/NN of/IN that/IN analogy/NN which/WDT subsists/NNS generally/RB between/IN the/DT fauna/NNS of/IN Europe/NNP and/CC of/IN North/NNP America/NNP ./. "/" On/IN my/PRP$ view/NN we/PRP must/MD suppose/VB that/IN American/NNP animals/NNS ,/, having/VBG in/IN most/RBS cases/NNS ordinary/JJ powers/NNS of/IN vision/NN ,/, slowly/RB migrated/VBN by/IN successive/JJ generations/NNS from/IN the/DT outer/JJ world/NN into/IN the/DT deeper/JJR and/CC deeper/JJR recesses/NNS of/IN the/DT Kentucky/NNP caves/NNS ,/, as/IN did/VBD European/JJ animals/NNS into/IN the/DT caves/NNS of/IN Europe/NNP ./. We/PRP have/VBP some/DT evidence/NN of/IN this/DT gradation/NN of/IN habit/NN ;/: for/IN ,/, as/IN Schiodte/NNP remarks/NNS ,/, "/" We/PRP accordingly/RB look/VB upon/IN the/DT subterranean/JJ faunas/NNS as/IN small/JJ ramifications/NNS which/WDT have/VBP penetrated/VBN into/IN the/DT earth/NN from/IN the/DT geographically/RB limited/JJ faunas/NNS of/IN the/DT adjacent/JJ tracts/NNS ,/, and/CC which/WDT ,/, as/IN they/PRP extended/VBN themselves/PRP into/IN darkness/NN ,/, have/VBP been/VBN accommodated/VBN to/TO surrounding/VBG circumstances/NNS ./. 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Murray/NNP observes/VBZ ,/, have/VBP not/RB as/IN yet/RB been/VBN found/VBD anywhere/RB except/IN in/IN caves/NNS ;/: yet/RB those/DT which/WDT inhabit/VBP the/DT several/JJ eaves/NNS of/IN Europe/NNP and/CC America/NNP are/VBP distinct/JJ ;/: but/CC it/PRP is/VBZ possible/JJ that/IN the/DT progenitors/NNS of/IN these/DT several/JJ species/NN ,/, whilst/NN they/PRP were/VBD furnished/VBN with/IN eyes/NNS ,/, may/MD formerly/RB have/VBP ranged/VBD over/IN both/DT continents/NNS ,/, and/CC then/RB have/VBP become/VB extinct/JJ ,/, excepting/VBG in/IN their/PRP$ present/JJ secluded/VBN abodes/NNS ./. 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For/IN instance/NN ,/, Alph/NNP ./. de/FW Candolle/NNP has/VBZ remarked/VBN that/IN winged/VBD seeds/NNS are/VBP never/RB found/VBD in/IN fruits/NNS which/WDT do/VBP not/RB open/JJ ;/: I/PRP should/MD explain/VB this/DT rule/NN by/IN the/DT impossibility/NN of/IN seeds/NNS gradually/RB becoming/VBG winged/VBD through/IN natural/JJ selection/NN ,/, unless/IN the/DT capsules/NNS were/VBD open/JJ ;/: for/IN in/IN this/DT case/NN alone/RB could/MD the/DT seeds/NNS ,/, which/WDT were/VBD a/DT little/JJ better/JJR adapted/VBN to/TO be/VB wafted/VBN by/IN the/DT wind/NN ,/, gain/NN an/DT advantage/NN over/IN others/NNS less/JJR well/RB fitted/VBN for/IN wide/JJ dispersal/NN ./. Compensation/NNP and/CC Economy/NNP of/IN Growth/NN The/DT elder/JJR Geoffroy/NNP and/CC Goethe/NNP propounded/VBD ,/, at/IN about/IN the/DT same/JJ time/NN ,/, their/PRP$ law/NN of/IN compensation/NN or/CC balancement/NN of/IN growth/NN ;/: or/CC ,/, as/IN Goethe/NNP expressed/VBN it/PRP ,/, "/" In/IN order/NN to/TO spend/VB on/IN one/CD side/NN ,/, nature/NN is/VBZ forced/VBN to/TO economise/NN on/IN the/DT other/JJ side/NN ./. "/" I/PRP think/VBP this/DT holds/VBZ true/JJ to/TO a/DT certain/JJ extent/NN with/IN our/PRP$ domestic/JJ productions/NNS :/: if/IN nourishment/NN flows/NNS to/TO one/CD part/NN or/CC organ/NN in/IN excess/JJ ,/, it/PRP rarely/RB flows/NNS ,/, at/IN least/JJS in/IN excess/JJ ,/, to/TO another/DT part/NN ;/: thus/RB it/PRP is/VBZ difficult/JJ to/TO get/VB a/DT cow/NN to/TO give/VB much/JJ milk/NN and/CC to/TO fatten/VB readily/RB ./. The/DT same/JJ varieties/NNS of/IN the/DT cabbage/NN do/VBP not/RB yield/VB abundant/JJ and/CC nutritious/JJ foliage/NN and/CC a/DT copious/JJ supply/NN of/IN oil/NN bearing/VBG seeds/NNS ./. When/WRB the/DT seeds/NNS in/IN our/PRP$ fruits/NNS become/VB atrophied/VBN ,/, the/DT fruit/NN itself/PRP gains/NNS largely/RB in/IN size/NN and/CC quality/NN ./. In/IN our/PRP$ poultry/NN ,/, a/DT large/JJ tuft/NN of/IN feathers/NNS on/IN the/DT head/NN is/VBZ generally/RB accompanied/VBN by/IN a/DT diminished/VBN comb/NN ,/, and/CC a/DT large/JJ beard/NN by/IN diminished/VBN wattles/NNS ./. With/IN species/NN in/IN a/DT state/NN of/IN nature/NN it/PRP can/MD hardly/RB be/VB maintained/VBN that/IN the/DT law/NN is/VBZ of/IN universal/JJ application/NN ;/: but/CC many/JJ good/JJ observers/NNS ,/, more/JJR especially/RB botanists/NNS ,/, believe/VBP in/IN its/PRP$ truth/NN ./. I/PRP will/MD not/RB ,/, however/RB ,/, here/RB give/VB any/DT instances/NNS ,/, for/IN I/PRP see/VB hardly/RB any/DT way/NN of/IN distinguishing/VBG between/IN the/DT effects/NNS ,/, on/IN the/DT one/CD hand/NN ,/, of/IN a/DT part/NN being/VBG largely/RB developed/VBN through/IN natural/JJ selection/NN and/CC another/DT and/CC adjoining/VBG part/NN being/VBG reduced/VBN by/IN this/DT same/JJ process/NN or/CC by/IN disuse/NN ,/, and/CC ,/, on/IN the/DT other/JJ hand/NN the/DT actual/JJ withdrawal/NN of/IN nutriment/NN from/IN one/CD part/NN owing/JJ to/TO the/DT excess/JJ of/IN growth/NN in/IN another/DT and/CC adjoining/VBG part/NN ./. I/PRP suspect/VBP ,/, also/RB ,/, that/IN some/DT of/IN the/DT cases/NNS of/IN compensation/NN which/WDT have/VBP been/VBN advanced/VBD ,/, and/CC likewise/RB some/DT other/JJ facts/NNS ,/, may/MD be/VB merged/VBN under/IN a/DT more/JJR general/JJ principle/NN ,/, namely/RB ,/, that/IN natural/JJ selection/NN is/VBZ continually/RB trying/VBG to/TO economise/NN every/DT part/NN of/IN the/DT organization/NN ./. If/IN under/IN changed/VBN conditions/NNS of/IN life/NN a/DT structure/NN ,/, before/IN useful/JJ ,/, becomes/VBZ less/JJR useful/JJ ,/, its/PRP$ diminution/NN will/MD be/VB favoured/VBN ,/, for/IN it/PRP will/MD profit/NN the/DT individual/JJ not/RB to/TO have/VB its/PRP$ nutriment/NN wasted/VBN in/IN building/NN up/IN an/DT useless/JJ structure/NN ./. I/PRP can/MD only/RB thus/RB understand/VB a/DT fact/NN with/IN which/WDT I/PRP was/VBD much/JJ struck/VBD when/WRB examining/VBG cirripedes/NNS ,/, and/CC of/IN which/WDT many/JJ analogous/JJ instances/NNS could/MD be/VB given/VBN :/: namely/RB ,/, that/IN when/WRB a/DT cirripede/NN is/VBZ parasitic/JJ within/IN another/DT cirripede/NN and/CC is/VBZ thus/RB protected/VBN ,/, it/PRP loses/VBZ more/JJR or/CC less/JJR completely/RB its/PRP$ own/JJ shell/NN or/CC carapace/NN ./. This/DT is/VBZ the/DT case/NN with/IN the/DT male/JJ Ibla/NNP ,/, and/CC in/IN a/DT truly/RB extraordinary/JJ manner/NN with/IN the/DT Proteolepas/NNP :/: for/IN the/DT carapace/NN in/IN all/DT other/JJ cirripedes/NNS consists/VBZ of/IN the/DT three/CD highly/RB important/JJ anterior/JJ segments/NNS of/IN the/DT head/NN enormously/RB developed/VBN ,/, and/CC furnished/VBN with/IN great/JJ nerves/NNS and/CC muscles/NNS ;/: but/CC in/IN the/DT parasitic/JJ and/CC protected/VBN Proteolepas/NNP ,/, the/DT whole/JJ anterior/JJ part/NN of/IN the/DT head/NN is/VBZ reduced/VBN to/TO the/DT merest/JJS rudiment/NN attached/VBN to/TO the/DT bases/NNS of/IN the/DT prehensile/NN antennae/NNS ./. Now/RB the/DT saving/VBG of/IN a/DT large/JJ and/CC complex/JJ structure/NN ,/, when/WRB rendered/VBN superfluous/JJ ,/, would/MD be/VB a/DT decided/VBD advantage/NN to/TO each/DT successive/JJ individual/JJ of/IN the/DT species/NN ;/: for/IN in/IN the/DT struggle/NN for/IN life/NN to/TO which/WDT every/DT animal/NN is/VBZ exposed/VBN ,/, each/DT would/MD have/VB a/DT better/JJR chance/NN of/IN supporting/VBG itself/PRP ,/, by/IN less/JJR nutriment/NN being/VBG wasted/VBN ./. Thus/RB ,/, as/IN I/PRP believe/VBP ,/, natural/JJ selection/NN will/MD tend/VB in/IN the/DT long/JJ run/VB to/TO reduce/VB any/DT part/NN of/IN the/DT organisation/NN ,/, as/IN soon/RB as/IN it/PRP becomes/VBZ ,/, through/IN changed/VBN habits/NNS ,/, superfluous/JJ ,/, without/IN by/IN any/DT means/VBZ causing/VBG some/DT other/JJ part/NN to/TO be/VB largely/RB developed/VBN in/IN a/DT corresponding/JJ degree/NN ./. And/CC ,/, conversely/RB ,/, that/IN natural/JJ selection/NN may/MD perfectly/RB well/RB succeed/VB in/IN largely/RB developing/VBG an/DT organ/NN without/IN requiring/VBG as/IN a/DT necessary/JJ compensation/NN the/DT reduction/NN of/IN some/DT adjoining/VBG part/NN ./. Multiple/NNP ,/, Rudimentary/NNP ,/, and/CC Lowly/RB organised/VBD Structures/NNS are/VBP Variable/NNP It/PRP seems/VBZ to/TO be/VB a/DT rule/NN ,/, as/IN remarked/VBD by/IN the/DT younger/JJR Geoffroy/NNP ,/, both/DT with/IN varieties/NNS and/CC species/NN ,/, that/IN when/WRB any/DT part/NN or/CC organ/NN is/VBZ repeated/VBN many/JJ times/NNS in/IN the/DT same/JJ individual/JJ (/( as/IN the/DT vertebrae/NNS in/IN snakes/NNS ,/, and/CC the/DT stamens/NNS in/IN polyandrous/JJ flowers/NNS )/SYM the/DT number/NN is/VBZ variable/JJ ;/: whereas/IN the/DT same/JJ part/NN or/CC organ/NN ,/, when/WRB it/PRP occurs/VBZ in/IN lesser/JJR numbers/NNS ,/, is/VBZ constant/JJ ./. The/DT same/JJ author/NN as/IN well/RB as/IN some/DT botanists/NNS have/VBP further/JJR remarked/VBD that/IN multiple/JJ parts/NNS are/VBP extremely/RB liable/JJ to/TO vary/VB in/IN structure/NN ./. As/IN "/" vegetable/NN repetition/NN ,/, "/" to/TO use/NN Prof/NNP ./. Owen's/NNP expression/NN ,/, is/VBZ a/DT sign/NN of/IN low/JJ organisation/NN ,/, the/DT foregoing/NN statements/NNS accord/NN with/IN the/DT common/JJ opinion/NN of/IN naturalists/NNS ,/, that/IN beings/NNS which/WDT stand/VB low/JJ in/IN the/DT scale/NN of/IN nature/NN are/VBP more/JJR variable/JJ than/IN those/DT which/WDT are/VBP higher/JJR ./. I/PRP presume/VB that/IN lowness/NN here/RB means/VBZ that/IN the/DT several/JJ parts/NNS of/IN the/DT organisation/NN have/VBP been/VBN but/CC little/JJ specialised/VBN for/IN particular/JJ functions/NNS ;/: and/CC as/IN long/JJ as/IN the/DT same/JJ part/NN has/VBZ to/TO perform/VB diversified/JJ work/NN ,/, we/PRP can/MD perhaps/RB see/VB why/WRB it/PRP should/MD remain/VB variable/JJ ,/, that/IN is/VBZ ,/, why/WRB natural/JJ selection/NN should/MD not/RB have/VBP preserved/VBN or/CC rejected/VBD each/DT little/JJ deviation/NN of/IN form/NN as/IN carefully/RB as/IN when/WRB the/DT part/NN has/VBZ to/TO serve/VB for/IN some/DT one/CD special/JJ purpose/NN ./. In/IN the/DT same/JJ way/NN ,/, a/DT knife/NN which/WDT has/VBZ to/TO cut/VB all/DT sorts/NNS of/IN things/NNS may/MD be/VB of/IN almost/RB any/DT shape/NN ;/: whilst/NN a/DT tool/NN for/IN some/DT particular/JJ purpose/NN must/MD be/VB of/IN some/DT particular/JJ shape/NN ./. Natural/NNP selection/NN ,/, it/PRP should/MD never/RB be/VB forgotten/VBN ,/, can/MD act/NN solely/RB through/IN and/CC for/IN the/DT advantage/NN of/IN each/DT being/VBG ./. Rudimentary/NNP parts/NNS ,/, as/IN it/PRP is/VBZ generally/RB admitted/VBD ,/, are/VBP apt/JJ to/TO be/VB highly/RB variable/JJ ./. We/PRP shall/MD have/VB to/TO recur/VB to/TO this/DT subject/NN ;/: and/CC I/PRP will/MD here/RB only/RB add/VB that/IN their/PRP$ variability/NN seems/VBZ to/TO result/NN from/IN their/PRP$ uselessness/NN ,/, and/CC consequently/RB from/IN natural/JJ selection/NN having/VBG had/VBD no/DT power/NN to/TO check/NN deviations/NNS in/IN their/PRP$ structure/NN ./. A/DT Part/NN developed/VBN in/IN any/DT Species/NNP in/IN an/DT extraordinary/JJ degree/NN or/CC manner/NN ,/, in/IN comparison/NN with/IN the/DT same/JJ Part/NN in/IN allied/VBN Species/NNP ,/, tends/VBZ to/TO be/VB highly/RB variable/JJ Several/JJ years/NNS ago/RB I/PRP was/VBD much/JJ struck/VBD by/IN a/DT remark/NN ,/, to/TO the/DT above/IN effect/NN ,/, made/VBN by/IN Mr/NNP ./. Waterhouse/NNP ./. Professor/NNP Owen/NNP ,/, also/RB ,/, seems/VBZ to/TO have/VB come/VB to/TO a/DT nearly/RB similar/JJ conclusion/NN ./. It/PRP is/VBZ hopeless/JJ to/TO attempt/NN to/TO convince/VB any/DT one/CD of/IN the/DT truth/NN of/IN the/DT above/IN proposition/NN without/IN giving/VBG the/DT long/JJ array/NN of/IN facts/NNS which/WDT I/PRP have/VBP collected/VBN ,/, and/CC which/WDT cannot/MD possibly/RB be/VB here/RB introduced/VBN ./. I/PRP can/MD only/RB state/NN my/PRP$ conviction/NN that/IN it/PRP is/VBZ a/DT rule/NN of/IN high/JJ generality/NN ./. I/PRP am/VBP aware/JJ of/IN several/JJ causes/NNS of/IN error/NN ,/, but/CC I/PRP hope/NN that/IN I/PRP have/VBP made/VBN due/JJ allowance/NN for/IN them/PRP ./. It/PRP should/MD be/VB understood/VBN that/IN the/DT rule/NN by/IN no/DT means/VBZ applies/VBZ to/TO any/DT part/NN ,/, however/RB unusually/RB developed/VBN ,/, unless/IN it/PRP be/VB unusually/RB developed/VBN in/IN one/CD species/NN or/CC in/IN a/DT few/JJ species/NN in/IN comparison/NN with/IN the/DT same/JJ part/NN in/IN many/JJ closely/RB allied/VBN species/NN ./. Thus/RB ,/, the/DT wing/NN of/IN a/DT bat/NN is/VBZ a/DT most/RBS abnormal/JJ structure/NN in/IN the/DT class/NN of/IN mammals/NNS ,/, but/CC the/DT rule/NN would/MD not/RB apply/VB here/RB ,/, because/IN the/DT whole/JJ group/NN of/IN bats/NNS possesses/VBZ wings/NNS ;/: it/PRP would/MD apply/VB only/RB if/IN some/DT one/CD species/NN had/VBD wings/NNS developed/VBN in/IN a/DT remarkable/JJ manner/NN in/IN comparison/NN with/IN the/DT other/JJ species/NN of/IN the/DT same/JJ genus/NN ./. The/DT rule/NN applies/VBZ very/RB strongly/RB in/IN the/DT case/NN of/IN secondary/JJ sexual/JJ characters/NNS ,/, when/WRB displayed/VBN in/IN any/DT unusual/JJ manner/NN ./. The/DT term/NN ,/, secondary/JJ sexual/JJ characters/NNS ,/, used/VBN by/IN Hunter/NNP ,/, relates/VBZ to/TO characters/NNS which/WDT are/VBP attached/VBN to/TO one/CD sex/NN ,/, but/CC are/VBP not/RB directly/RB connected/VBN with/IN the/DT act/NN of/IN reproduction/NN ./. The/DT rule/NN applies/VBZ to/TO males/NNS and/CC females/NNS ;/: but/CC more/JJR rarely/RB to/TO the/DT females/NNS ,/, as/IN they/PRP seldom/RB offer/NN remarkable/JJ secondary/JJ sexual/JJ characters/NNS ./. The/DT rule/NN being/VBG so/RB plainly/RB applicable/JJ in/IN the/DT case/NN of/IN secondary/JJ sexual/JJ characters/NNS ,/, may/MD be/VB due/JJ to/TO the/DT great/JJ variability/NN of/IN these/DT characters/NNS ,/, whether/IN or/CC not/RB displayed/VBN in/IN any/DT unusual/JJ manner/NN of/IN which/WDT fact/NN I/PRP think/VBP there/EX can/MD be/VB little/JJ doubt/NN ./. But/CC that/IN our/PRP$ rule/NN is/VBZ not/RB confined/VBN to/TO secondary/JJ sexual/JJ characters/NNS is/VBZ clearly/RB shown/VBN in/IN the/DT case/NN of/IN hermaphrodite/NN cirripedes/NNS ;/: I/PRP particularly/RB attended/VBD to/TO Mr/NNP ./. Waterhouse's/NNP remark/NN ,/, whilst/NN investigating/VBG this/DT Order/NNP ,/, and/CC I/PRP am/VBP fully/RB convinced/VBN that/IN the/DT rule/NN almost/RB always/RB holds/VBZ good/JJ ./. I/PRP shall/MD ,/, in/IN a/DT future/NN work/NN ,/, give/VB a/DT list/NN of/IN all/DT the/DT more/JJR remarkable/JJ cases/NNS ;/: I/PRP will/MD here/RB give/VB only/RB one/CD ,/, as/IN it/PRP illustrates/VBZ the/DT rule/NN in/IN its/PRP$ largest/JJS application/NN ./. The/DT opereular/JJ valves/NNS of/IN sessile/NN cirripedes/NNS (/( rock/NN barnacles/NNS )/SYM are/VBP ,/, in/IN every/DT sense/NN of/IN the/DT word/NN ,/, very/RB important/JJ structures/NNS ,/, and/CC they/PRP differ/VBP extremely/RB little/JJ even/RB in/IN distinct/JJ genera/NN ;/: but/CC in/IN the/DT several/JJ species/NN of/IN one/CD genus/NN ,/, Pyrgoma/NNP ,/, these/DT valves/NNS present/JJ a/DT marvelous/JJ amount/NN of/IN diversification/NN ;/: the/DT homologous/RB valves/NNS in/IN the/DT different/JJ species/NN being/VBG sometimes/RB wholly/RB unlike/IN in/IN shape/NN ;/: and/CC the/DT amount/NN of/IN variation/NN in/IN the/DT individuals/NNS of/IN the/DT same/JJ species/NN is/VBZ so/RB great/JJ ,/, that/IN it/PRP is/VBZ no/DT exaggeration/NN to/TO state/NN that/IN the/DT varieties/NNS of/IN the/DT same/JJ species/NN differ/VBP more/JJR from/IN each/DT other/JJ in/IN the/DT characters/NNS derived/VBN from/IN these/DT important/JJ organs/NNS ,/, than/IN do/VBP the/DT species/NN belonging/VBG to/TO other/JJ distinct/JJ genera/NN ./. As/IN with/IN birds/NNS the/DT individuals/NNS of/IN the/DT same/JJ species/NN ,/, inhabiting/VBG the/DT same/JJ country/NN ,/, vary/VBP extremely/RB little/JJ ,/, I/PRP have/VBP particularly/RB attended/VBD to/TO them/PRP ;/: and/CC the/DT rule/NN certainly/RB seems/VBZ to/TO hold/VB good/JJ in/IN this/DT class/NN ./. I/PRP cannot/MD make/VB out/IN that/IN it/PRP applies/VBZ to/TO plants/NNS ,/, and/CC this/DT would/MD have/VB seriously/RB shaken/VBN my/PRP$ belief/NN in/IN its/PRP$ truth/NN ,/, had/VBD not/RB the/DT great/JJ variability/NN in/IN plants/NNS made/VBN it/PRP particularly/RB difficult/JJ to/TO compare/VB their/PRP$ relative/JJ degrees/NNS of/IN variability/NN ./. When/WRB we/PRP see/VB any/DT part/NN or/CC organ/NN developed/VBN in/IN a/DT remarkable/JJ degree/NN or/CC manner/NN in/IN a/DT species/NN ,/, the/DT fair/JJ presumption/NN is/VBZ that/IN it/PRP is/VBZ of/IN high/JJ importance/NN to/TO that/IN species/NN :/: nevertheless/RB it/PRP is/VBZ in/IN this/DT case/NN eminently/RB liable/JJ to/TO variation/NN ./. Why/WRB should/MD this/DT be/VB so/RB ?/. On/IN the/DT view/NN that/IN each/DT species/NN has/VBZ been/VBN independently/RB created/VBN ,/, with/IN all/DT its/PRP$ parts/NNS as/IN we/PRP now/RB see/VB them/PRP ,/, I/PRP can/MD see/VB no/DT explanation/NN ./. But/CC on/IN the/DT view/NN that/IN groups/NNS of/IN species/NN are/VBP descended/VBD from/IN some/DT other/JJ species/NN ,/, and/CC have/VBP been/VBN modified/VBN through/IN natural/JJ selection/NN ,/, I/PRP think/VBP we/PRP can/MD obtain/VB some/DT light/NN ./. First/NNP let/VB me/PRP make/VB some/DT preliminary/JJ remarks/NNS ./. If/IN ,/, in/IN our/PRP$ domestic/JJ animals/NNS ,/, any/DT part/NN or/CC the/DT whole/JJ animal/NN be/VB neglected/VBN ,/, and/CC no/DT selection/NN be/VB applied/VBN ,/, that/IN part/NN (/( for/IN instance/NN ,/, the/DT comb/NN in/IN the/DT Dorking/VBG fowl/NN )/SYM or/CC the/DT whole/JJ breed/NN will/MD cease/VB to/TO have/VB a/DT uniform/NN character/NN :/: and/CC the/DT breed/NN may/MD be/VB said/VBD to/TO be/VB degenerating/VBG ./. In/IN rudimentary/JJ organs/NNS ,/, and/CC in/IN those/DT which/WDT have/VBP been/VBN but/CC little/JJ specialised/VBN for/IN any/DT particular/JJ purpose/NN ,/, and/CC perhaps/RB in/IN polymorphic/JJ groups/NNS ,/, we/PRP see/VB a/DT nearly/RB parallel/JJ case/NN ;/: for/IN in/IN such/JJ cases/NNS natural/JJ selection/NN either/DT has/VBZ not/RB or/CC cannot/MD have/VB come/VB into/IN full/JJ play/VB ,/, and/CC thus/RB the/DT organisation/NN is/VBZ left/VBN in/IN a/DT fluctuating/VBG condition/NN ./. But/CC what/WP here/RB more/JJR particularly/RB concerns/NNS us/PRP is/VBZ ,/, that/IN those/DT points/NNS in/IN our/PRP$ domestic/JJ animals/NNS ,/, which/WDT at/IN the/DT present/JJ time/NN are/VBP undergoing/VBG rapid/JJ change/NN by/IN continued/VBD selection/NN ,/, are/VBP also/RB eminently/RB liable/JJ to/TO variation/NN ./. Look/VB at/IN the/DT individuals/NNS of/IN the/DT same/JJ breed/NN of/IN the/DT pigeon/NN ,/, and/CC see/VB what/WP a/DT prodigious/JJ amount/NN of/IN difference/NN there/EX is/VBZ in/IN the/DT beaks/NNS of/IN tumblers/NNS ,/, in/IN the/DT beaks/NNS and/CC wattle/NN of/IN carriers/NNS ,/, in/IN the/DT carriage/NN and/CC tail/NN of/IN fantails/NNS ,/, &c/NN ./. ,/, these/DT being/VBG the/DT points/NNS now/RB mainly/RB attended/VBD to/TO by/IN English/NNP fanciers/NNS ./. Even/RB in/IN the/DT same/JJ sub/NN breed/NN ,/, as/IN in/IN that/IN of/IN the/DT short/JJ faced/VBN tumbler/NN ,/, it/PRP is/VBZ notoriously/RB difficult/JJ to/TO breed/NN nearly/RB perfect/JJ birds/NNS ,/, many/JJ departing/VBG widely/RB from/IN the/DT standard/JJ ./. There/EX may/MD truly/RB be/VB said/VBD to/TO be/VB a/DT constant/JJ struggle/NN going/VBG on/IN between/IN ,/, on/IN the/DT one/CD hand/NN ,/, the/DT tendency/NN to/TO reversion/NN to/TO a/DT less/JJR perfect/JJ state/NN ,/, as/IN well/RB as/IN an/DT innate/JJ tendency/NN to/TO new/JJ variations/NNS ,/, and/CC ,/, on/IN the/DT other/JJ hand/NN ,/, the/DT power/NN of/IN steady/JJ selection/NN to/TO keep/VB the/DT breed/NN true/JJ ./. In/IN the/DT long/JJ run/VB selection/NN gains/NNS the/DT day/NN ,/, and/CC we/PRP do/VBP not/RB expect/VBP to/TO fail/VB so/RB completely/RB as/IN to/TO breed/NN a/DT bird/NN as/IN coarse/JJ as/IN a/DT common/JJ tumbler/NN pigeon/NN from/IN a/DT good/JJ short/JJ faced/VBN strain/NN ./. 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That/DT the/DT struggle/NN between/IN natural/JJ selection/NN on/IN the/DT one/CD hand/NN ,/, and/CC the/DT tendency/NN to/TO reversion/NN and/CC variability/NN on/IN the/DT other/JJ hand/NN ,/, will/MD in/IN the/DT course/NN of/IN time/NN cease/VB ;/: and/CC that/IN the/DT most/RBS abnormally/RB developed/VBN organs/NNS may/MD be/VB made/VBN constant/JJ ,/, I/PRP see/VB no/DT reason/NN to/TO doubt/NN ./. Hence/RB ,/, when/WRB an/DT organ/NN ,/, however/RB abnormal/JJ it/PRP may/MD be/VB ,/, has/VBZ been/VBN transmitted/VBN in/IN approximately/RB the/DT same/JJ condition/NN to/TO many/JJ modified/VBN descendants/NNS ,/, as/IN in/IN the/DT case/NN of/IN the/DT wing/NN of/IN the/DT bat/NN ,/, it/PRP must/MD have/VB existed/VBD ,/, according/VBG to/TO our/PRP$ theory/NN ,/, for/IN an/DT immense/JJ period/NN in/IN nearly/RB the/DT same/JJ state/NN ;/: and/CC thus/RB it/PRP has/VBZ come/VB not/RB to/TO be/VB more/JJR variable/JJ than/IN any/DT other/JJ structure/NN ./. 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It/PRP is/VBZ notorious/JJ that/IN specific/JJ characters/NNS are/VBP more/JJR variable/JJ than/IN generic/JJ ./. To/TO explain/VB by/IN a/DT simple/JJ example/NN what/WP is/VBZ meant/VBN :/: if/IN in/IN a/DT large/JJ genus/NN of/IN plants/NNS some/DT species/NN had/VBD blue/JJ flowers/NNS and/CC some/DT had/VBD red/JJ ,/, the/DT colour/NN would/MD be/VB only/RB a/DT specific/JJ character/NN ,/, and/CC no/DT one/CD would/MD be/VB surprised/VBN at/IN one/CD of/IN the/DT blue/JJ species/NN varying/VBG into/IN red/JJ ,/, or/CC conversely/RB ;/: but/CC if/IN all/DT the/DT species/NN had/VBD blue/JJ flowers/NNS ,/, the/DT colour/NN would/MD become/VB a/DT generic/JJ character/NN ,/, and/CC its/PRP$ variation/NN would/MD be/VB a/DT more/JJR unusual/JJ circumstance/NN ./. 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Or/CC to/TO state/NN the/DT case/NN in/IN another/DT manner/NN :/: the/DT points/NNS in/IN which/WDT all/DT the/DT species/NN of/IN a/DT genus/NN resemble/VB each/DT other/JJ ,/, and/CC in/IN which/WDT they/PRP differ/VBP from/IN allied/VBN genera/NN ,/, are/VBP called/VBN generic/JJ characters/NNS ;/: and/CC these/DT characters/NNS may/MD be/VB attributed/VBD to/TO inheritance/NN from/IN a/DT common/JJ progenitor/NN ,/, for/IN it/PRP can/MD rarely/RB have/VBP happened/VBD that/IN natural/JJ selection/NN will/MD have/VB modified/VBN several/JJ distinct/JJ species/NN ,/, fitted/VBN to/TO more/JJR or/CC less/JJR widely/RB different/JJ habits/NNS ,/, in/IN exactly/RB the/DT same/JJ manner/NN :/: and/CC as/IN these/DT so/RB called/VBN generic/JJ characters/NNS have/VBP been/VBN inherited/VBN from/IN before/IN the/DT period/NN when/WRB the/DT several/JJ species/NN first/JJ branched/VBN off/IN from/IN their/PRP$ common/JJ progenitor/NN ,/, and/CC subsequently/RB have/VBP not/RB varied/VBN or/CC come/VB to/TO differ/VB in/IN any/DT degree/NN ,/, or/CC only/RB in/IN a/DT slight/JJ degree/NN ,/, it/PRP is/VBZ not/RB probable/JJ that/IN they/PRP should/MD vary/VB at/IN the/DT present/JJ day/NN ./. On/IN the/DT other/JJ hand/NN ,/, the/DT points/NNS in/IN which/WDT species/NN differ/VBP from/IN other/JJ species/NN of/IN the/DT same/JJ genus/NN are/VBP called/VBN specific/JJ characters/NNS ;/: and/CC as/IN these/DT specific/JJ characters/NNS have/VBP varied/VBN and/CC come/VB to/TO differ/VB since/IN the/DT period/NN when/WRB the/DT species/NN branched/VBN off/IN from/IN a/DT common/JJ progenitor/NN ,/, it/PRP is/VBZ probable/JJ that/IN they/PRP should/MD still/RB often/RB be/VB in/IN some/DT degree/NN variable/JJ ,/, at/IN least/JJS more/JJR variable/JJ than/IN those/DT parts/NNS of/IN the/DT organisation/NN which/WDT have/VBP for/IN a/DT very/RB long/JJ period/NN remained/VBD constant/JJ ./. Secondary/JJ Sexual/NNP Characters/NNS Variable/NNP ./. I/PRP think/VBP it/PRP will/MD be/VB admitted/VBD by/IN naturalists/NNS ,/, without/IN my/PRP$ entering/VBG on/IN details/NNS ,/, that/IN secondary/JJ sexual/JJ characters/NNS are/VBP highly/RB variable/JJ ./. It/PRP will/MD also/RB be/VB admitted/VBD that/IN species/NN of/IN the/DT same/JJ group/NN differ/VBP from/IN each/DT other/JJ more/JJR widely/RB in/IN their/PRP$ secondary/JJ sexual/JJ characters/NNS ,/, than/IN in/IN other/JJ parts/NNS of/IN their/PRP$ organisation/NN :/: compare/VB ,/, for/IN instance/NN ,/, the/DT amount/NN of/IN difference/NN between/IN the/DT males/NNS of/IN gallinaceous/JJ birds/NNS ,/, in/IN which/WDT secondary/JJ sexual/JJ characters/NNS are/VBP strongly/RB displayed/VBN ,/, with/IN the/DT amount/NN of/IN difference/NN between/IN the/DT females/NNS ./. The/DT cause/NN of/IN the/DT original/JJ variability/NN of/IN these/DT characters/NNS is/VBZ not/RB manifest/JJ ;/: but/CC we/PRP can/MD see/VB why/WRB they/PRP should/MD not/RB have/VBP been/VBN rendered/VBN as/IN constant/JJ and/CC uniform/NN as/IN others/NNS ,/, for/IN they/PRP are/VBP accumulated/VBN by/IN sexual/JJ selection/NN ,/, which/WDT is/VBZ less/JJR rigid/JJ in/IN its/PRP$ action/NN than/IN ordinary/JJ selection/NN ,/, as/IN it/PRP does/VBZ not/RB entail/VB death/NN ,/, but/CC only/RB gives/VBZ fewer/JJR off/IN spring/NN to/TO the/DT less/JJR favoured/VBN males/NNS ./. Whatever/WDT the/DT cause/NN may/MD be/VB of/IN the/DT variability/NN of/IN secondary/JJ sexual/JJ characters/NNS ,/, as/IN they/PRP are/VBP highly/RB variable/JJ ,/, sexual/JJ selection/NN will/MD have/VB had/VBD a/DT wide/JJ scope/NN for/IN action/NN ,/, and/CC may/MD thus/RB have/VBP succeeded/VBN in/IN giving/VBG to/TO the/DT species/NN of/IN the/DT same/JJ group/NN a/DT greater/JJR amount/NN of/IN difference/NN in/IN these/DT than/IN in/IN other/JJ respects/NNS ./. It/PRP is/VBZ a/DT remarkable/JJ fact/NN ,/, that/IN the/DT secondary/JJ differences/NNS between/IN the/DT two/CD sexes/NNS of/IN the/DT same/JJ species/NN are/VBP generally/RB displayed/VBN in/IN the/DT very/RB same/JJ parts/NNS of/IN the/DT organisation/NN in/IN which/WDT the/DT species/NN of/IN the/DT same/JJ genus/NN differ/VBP from/IN each/DT other/JJ ./. Of/IN this/DT fact/NN I/PRP will/MD give/VB in/IN illustration/NN the/DT two/CD first/JJ instances/NNS which/WDT happen/VB to/TO stand/VB on/IN my/PRP$ list/NN ;/: and/CC as/IN the/DT differences/NNS in/IN these/DT cases/NNS are/VBP of/IN a/DT very/RB unusual/JJ nature/NN ,/, the/DT relation/NN can/MD hardly/RB be/VB accidental/JJ ./. The/DT same/JJ number/NN of/IN joints/NNS in/IN the/DT tarsi/NN is/VBZ a/DT character/NN common/JJ to/TO very/RB large/JJ groups/NNS of/IN beetles/NNS ,/, but/CC in/IN the/DT Engidoe/NNP ,/, as/IN Westwood/NNP has/VBZ remarked/VBN ,/, the/DT number/NN varies/VBZ greatly/RB ;/: and/CC the/DT number/NN likewise/RB differs/VBZ in/IN the/DT two/CD sexes/NNS of/IN the/DT same/JJ species/NN ./. 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"/" This/DT relation/NN has/VBZ a/DT clear/JJ meaning/NN on/IN my/PRP$ view/NN :/: I/PRP look/VB at/IN all/DT the/DT species/NN of/IN the/DT same/JJ genus/NN as/IN having/VBG as/IN certainly/RB descended/VBD from/IN a/DT common/JJ progenitor/NN ,/, as/IN have/VBP the/DT two/CD sexes/NNS of/IN any/DT one/CD species/NN ./. 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The/DT frequent/JJ presence/NN of/IN fourteen/CD or/CC even/RB sixteen/CD tail/NN feathers/NNS in/IN the/DT pouter/NN may/MD be/VB considered/VBN as/IN a/DT variation/NN representing/VBG the/DT normal/JJ structure/NN of/IN another/DT race/NN ,/, the/DT fan/NN tail/NN ./. I/PRP presume/VB that/IN no/DT one/CD will/MD doubt/NN that/IN all/DT such/JJ analogous/JJ variations/NNS are/VBP due/JJ to/TO the/DT several/JJ races/NNS of/IN the/DT pigeon/NN having/VBG inherited/VBN from/IN a/DT common/JJ parent/NN the/DT same/JJ constitution/NN and/CC tendency/NN to/TO variation/NN ,/, when/WRB acted/VBD on/IN by/IN similar/JJ unknown/JJ influences/NNS ./. 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Walsh/NNP ,/, who/WP has/VBZ grouped/VBN them/PRP under/IN his/PRP$ law/NN of/IN Equable/NNP Variability/NN ./. With/IN pigeons/NNS ,/, however/RB ,/, we/PRP have/VBP another/DT case/NN ,/, namely/RB ,/, the/DT occasional/JJ appearance/NN in/IN all/DT the/DT breeds/NNS ,/, of/IN slaty/JJ blue/JJ birds/NNS with/IN two/CD black/JJ bars/NNS on/IN the/DT wings/NNS ,/, white/JJ loins/NNS ,/, a/DT bar/NN at/IN the/DT end/NN of/IN the/DT tail/NN ,/, with/IN the/DT outer/JJ feathers/NNS externally/RB edged/VBD near/IN their/PRP$ basis/NN with/IN white/JJ ./. As/IN all/DT these/DT marks/NNS are/VBP characteristic/JJ of/IN the/DT parent/NN rock/NN pigeon/NN ,/, I/PRP presume/VB that/IN no/DT one/CD will/MD doubt/NN that/IN this/DT is/VBZ a/DT case/NN of/IN reversion/NN ,/, and/CC not/RB of/IN a/DT new/JJ yet/RB analogous/JJ variation/NN appearing/VBG in/IN the/DT several/JJ breeds/NNS ./. 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But/CC when/WRB a/DT breed/NN has/VBZ been/VBN crossed/VBD only/RB once/RB by/IN some/DT other/JJ breed/NN ,/, the/DT offspring/NN occasionally/RB show/NN for/IN many/JJ generations/NNS a/DT tendency/NN to/TO revert/VB in/IN character/NN to/TO the/DT foreign/JJ breed/NN some/DT say/VBP ,/, for/IN a/DT dozen/NN or/CC even/RB a/DT score/NN of/IN generations/NNS ./. After/IN twelve/CD generations/NNS ,/, the/DT proportion/NN of/IN blood/NN ,/, to/TO use/NN a/DT common/JJ expression/NN ,/, from/IN one/CD ancestor/NN ,/, is/VBZ only/RB 1/CD in/IN 2048/CD ;/: and/CC yet/RB ,/, as/IN we/PRP see/VB ,/, it/PRP is/VBZ generally/RB believed/VBD that/IN a/DT tendency/NN to/TO reversion/NN is/VBZ retained/VBN by/IN this/DT remnant/NN of/IN foreign/JJ blood/NN ./. 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When/WRB a/DT character/NN which/WDT has/VBZ been/VBN lost/VBD in/IN a/DT breed/NN ,/, reappears/VBZ after/IN a/DT great/JJ number/NN of/IN generations/NNS ,/, the/DT most/RBS probable/JJ hypothesis/NN is/VBZ ,/, not/RB that/IN one/CD individual/JJ suddenly/RB takes/VBZ after/IN an/DT ancestor/NN removed/VBN by/IN some/DT hundred/CD generations/NNS ,/, but/CC that/IN in/IN each/DT successive/JJ generation/NN the/DT character/NN in/IN question/NN has/VBZ been/VBN lying/VBG latent/JJ ,/, and/CC at/IN last/JJ ,/, under/IN unknown/JJ favourable/JJ conditions/NNS ,/, is/VBZ developed/VBN ./. With/IN the/DT barb/NN pigeon/NN ,/, for/IN instance/NN ,/, which/WDT very/RB rarely/RB produces/VBZ a/DT blue/JJ bird/NN ,/, it/PRP is/VBZ probable/JJ that/IN there/EX is/VBZ a/DT latent/JJ tendency/NN in/IN each/DT generation/NN to/TO produce/VB blue/JJ plumage/NN ./. 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As/IN all/DT the/DT species/NN of/IN the/DT same/JJ genus/NN are/VBP supposed/VBN to/TO be/VB descended/VBD from/IN a/DT common/JJ progenitor/NN ,/, it/PRP might/MD be/VB expected/VBN that/IN they/PRP would/MD occasionally/RB vary/VBP in/IN an/DT analogous/JJ manner/NN ;/: so/RB that/IN the/DT varieties/NNS of/IN two/CD or/CC more/JJR species/NN would/MD resemble/VB each/DT other/JJ ,/, or/CC that/IN a/DT variety/NN of/IN one/CD species/NN would/MD resemble/VB in/IN certain/JJ characters/NNS another/DT and/CC distinct/JJ species/NN ,/, this/DT other/JJ species/NN being/VBG ,/, according/VBG to/TO our/PRP$ view/NN ,/, only/RB a/DT well/RB marked/VBN and/CC permanent/JJ variety/NN ./. But/CC characters/NNS exclusively/RB due/JJ to/TO analogous/JJ variation/NN would/MD probably/RB be/VB of/IN an/DT unimportant/JJ nature/NN ,/, for/IN the/DT preservation/NN of/IN all/DT functionally/RB important/JJ characters/NNS will/MD have/VB been/VBN determined/VBN through/IN natural/JJ selection/NN ,/, in/IN accordance/NN with/IN the/DT different/JJ habits/NNS of/IN the/DT species/NN ./. It/PRP might/MD further/JJR be/VB expected/VBN that/IN the/DT species/NN of/IN the/DT same/JJ genus/NN would/MD occasionally/RB exhibit/NN reversions/NNS to/TO long/JJ lost/VBD characters/NNS ./. As/IN ,/, however/RB ,/, we/PRP do/VBP not/RB know/VB the/DT common/JJ ancestors/NNS of/IN any/DT natural/JJ group/NN ,/, we/PRP cannot/MD distinguish/VB between/IN reversionary/JJ and/CC analogous/JJ characters/NNS ./. If/IN ,/, for/IN instance/NN ,/, we/PRP did/VBD not/RB know/VB that/IN the/DT parent/NN rock/NN pigeon/NN was/VBD not/RB feather/NN footed/VBN or/CC turn/VB crowned/VBN ,/, we/PRP could/MD not/RB have/VBP told/VBD ,/, whether/IN such/JJ characters/NNS in/IN our/PRP$ domestic/JJ breeds/NNS were/VBD reversions/NNS or/CC only/RB analogous/JJ variations/NNS ;/: but/CC we/PRP might/MD have/VB inferred/VBD that/IN the/DT blue/JJ colour/NN was/VBD a/DT case/NN of/IN reversion/NN from/IN the/DT number/NN of/IN the/DT markings/NNS ,/, which/WDT are/VBP correlated/JJ with/IN this/DT tint/VBP ,/, and/CC which/WDT would/MD not/RB probably/RB have/VBP all/DT appeared/VBD together/RB from/IN simple/JJ variation/NN ./. More/RBR especially/RB we/PRP might/MD have/VB inferred/VBD this/DT ,/, from/IN the/DT blue/JJ colour/NN and/CC the/DT several/JJ marks/NNS so/RB often/RB appearing/VBG when/WRB differently/RB coloured/JJ breeds/NNS are/VBP crossed/VBD ./. Hence/RB ,/, although/IN under/IN nature/NN it/PRP must/MD generally/RB be/VB left/VBN doubtful/JJ ,/, what/WP cases/NNS are/VBP reversions/NNS to/TO formerly/RB existing/VBG characters/NNS ,/, and/CC what/WP are/VBP new/JJ but/CC analogous/JJ variations/NNS ,/, yet/RB we/PRP ought/MD ,/, on/IN our/PRP$ theory/NN ,/, sometimes/RB to/TO find/VB the/DT varying/VBG offspring/NN of/IN a/DT species/NN assuming/VBG characters/NNS which/WDT are/VBP already/RB present/JJ in/IN other/JJ members/NNS of/IN the/DT same/JJ group/NN ./. And/CC this/DT undoubtedly/RB is/VBZ the/DT case/NN ./. The/DT difficulty/NN in/IN distinguishing/VBG variable/JJ species/NN is/VBZ largely/RB due/JJ to/TO the/DT varieties/NNS mocking/VBG ,/, as/IN it/PRP were/VBD ,/, other/JJ species/NN of/IN the/DT same/JJ genus/NN ./. A/DT considerable/JJ catalogue/NN ,/, also/RB ,/, could/MD be/VB given/VBN of/IN forms/NNS intermediate/JJ between/IN two/CD other/JJ forms/NNS ,/, which/WDT themselves/PRP can/MD only/RB doubtfully/RB be/VB ranked/VBD as/IN species/NN ;/: and/CC this/DT shows/VBZ ,/, unless/IN all/DT these/DT closely/RB allied/VBN forms/NNS be/VB considered/VBN as/IN independently/RB created/VBN species/NN ,/, that/IN they/PRP have/VBP in/IN varying/VBG assumed/VBN some/DT of/IN the/DT characters/NNS of/IN the/DT others/NNS ./. But/CC the/DT best/JJS evidence/NN of/IN analogous/JJ variations/NNS is/VBZ afforded/VBN by/IN parts/NNS or/CC organs/NNS which/WDT are/VBP generally/RB constant/JJ in/IN character/NN ,/, but/CC which/WDT occasionally/RB vary/VBP so/RB as/IN to/TO resemble/VB ,/, in/IN some/DT degree/NN ,/, the/DT same/JJ part/NN or/CC organ/NN in/IN an/DT allied/VBN species/NN ./. I/PRP have/VBP collected/VBN a/DT long/JJ list/NN of/IN such/JJ cases/NNS ;/: but/CC here/RB ,/, as/IN before/IN ,/, I/PRP lie/VB under/IN the/DT great/JJ disadvantage/NN of/IN not/RB being/VBG able/JJ to/TO give/VB them/PRP ./. I/PRP can/MD only/RB repeat/VB that/IN such/JJ cases/NNS certainly/RB occur/VB ,/, and/CC seem/VB to/TO me/PRP very/RB remarkable/JJ ./. I/PRP will/MD ,/, however/RB ,/, give/VB one/CD curious/JJ and/CC complex/JJ case/NN ,/, not/RB indeed/RB as/IN affecting/VBG any/DT important/JJ character/NN ,/, but/CC from/IN occurring/VBG in/IN several/JJ species/NN of/IN the/DT same/JJ genus/NN ,/, partly/RB under/IN domestication/NN and/CC partly/RB under/IN nature/NN ./. It/PRP is/VBZ a/DT case/NN almost/RB certainly/RB of/IN reversion/NN ./. The/DT ass/NN sometimes/RB has/VBZ very/RB distinct/JJ transverse/JJ bars/NNS on/IN its/PRP$ legs/NNS ,/, like/IN those/DT on/IN the/DT legs/NNS of/IN the/DT zebra/NN :/: it/PRP has/VBZ been/VBN asserted/VBD that/IN these/DT are/VBP plainest/JJS in/IN the/DT foal/NN ,/, and/CC ,/, from/IN inquiries/NNS which/WDT I/PRP have/VBP made/VBN ,/, I/PRP believe/VBP this/DT to/TO be/VB true/JJ ./. The/DT stripe/NN on/IN the/DT shoulder/NN is/VBZ sometimes/RB double/JJ ,/, and/CC is/VBZ very/RB variable/JJ in/IN length/NN and/CC outline/NN ./. A/DT white/JJ ass/NN ,/, but/CC not/RB an/DT albino/NN ,/, has/VBZ been/VBN described/VBN without/IN either/DT spinal/JJ or/CC shoulder/NN stripe/NN :/: and/CC these/DT stripes/NNS are/VBP sometimes/RB very/RB obscure/JJ ,/, or/CC actually/RB quite/RB lost/VBD ,/, in/IN dark/JJ coloured/JJ asses/NNS ./. The/DT koulan/NN of/IN Pallas/NNP is/VBZ said/VBD to/TO have/VB been/VBN seen/VBN with/IN a/DT double/JJ shoulder/NN stripe/NN ./. Mr/NNP ./. Blyth/NNP has/VBZ seen/VBN a/DT specimen/NN of/IN the/DT hemionus/JJ with/IN a/DT distinct/JJ shoulder/NN stripe/NN ,/, though/IN it/PRP properly/RB has/VBZ none/NN ;/: and/CC I/PRP have/VBP been/VBN informed/VBN by/IN Colonel/NNP Poole/NNP that/IN the/DT foals/NNS of/IN this/DT species/NN are/VBP generally/RB striped/JJ on/IN the/DT legs/NNS ,/, and/CC faintly/RB on/IN the/DT shoulder/NN ./. The/DT quagga/NN ,/, though/IN so/RB plainly/RB barred/VBN like/IN a/DT zebra/NN over/IN the/DT body/NN ,/, is/VBZ without/IN bars/NNS on/IN the/DT legs/NNS ;/: but/CC Dr/NNP ./. Gray/NNP has/VBZ figured/VBN one/CD specimen/NN with/IN very/RB distinct/JJ zebra/NN like/IN bars/NNS on/IN the/DT hocks/NNS ./. With/IN respect/NN to/TO the/DT horse/NN ,/, I/PRP have/VBP collected/VBN cases/NNS in/IN England/NNP of/IN the/DT spinal/JJ stripe/NN in/IN horses/NNS of/IN the/DT most/RBS distinct/JJ breeds/NNS ,/, and/CC of/IN all/DT colours/NNS :/: transverse/JJ bars/NNS on/IN the/DT legs/NNS are/VBP not/RB rare/JJ in/IN duns/NNS ,/, mouse/NN duns/NNS ,/, and/CC in/IN one/CD instance/NN in/IN a/DT chestnut/NN a/DT faint/JJ shoulder/NN stripe/NN may/MD sometimes/RB be/VB seen/VBN in/IN duns/NNS ,/, and/CC I/PRP have/VBP seen/VBN a/DT trace/NN in/IN a/DT bay/NN horse/NN ./. My/PRP$ son/NN made/VBN a/DT careful/JJ examination/NN and/CC sketch/NN for/IN me/PRP of/IN a/DT dun/NN Belgian/JJ cart/NN horse/NN with/IN a/DT double/JJ stripe/NN on/IN each/DT shoulder/NN and/CC with/IN leg/NN stripes/NNS ;/: I/PRP have/VBP myself/PRP seen/VBN a/DT dun/NN Devonshire/NNP pony/NN ,/, and/CC a/DT small/JJ dun/NN Welsh/NNP pony/NN has/VBZ been/VBN carefully/RB described/VBN to/TO me/PRP ,/, both/DT with/IN three/CD parallel/JJ stripes/NNS on/IN each/DT shoulder/NN ./. In/IN the/DT north/RB west/NN part/NN of/IN India/NNP the/DT kattywar/NN breed/NN of/IN horses/NNS is/VBZ so/RB generally/RB striped/JJ ,/, that/IN ,/, as/IN I/PRP hear/VB from/IN Colonel/NNP Poole/NNP ,/, who/WP examined/VBD this/DT breed/NN for/IN the/DT Indian/NNP Government/NNP ,/, a/DT horse/NN without/IN stripes/NNS is/VBZ not/RB considered/VBN as/IN purely/RB bred/VBN ./. 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I/PRP have/VBP myself/PRP recently/RB bred/VBN a/DT foal/NN from/IN a/DT bay/NN mare/NN (/( offspring/NN of/IN a/DT Turkoman/NNP horse/NN and/CC a/DT Flemish/NNP mare/NN )/SYM by/IN a/DT bay/NN English/NNP race/NN horse/NN ;/: this/DT foal/NN when/WRB a/DT week/NN old/JJ was/VBD marked/VBN on/IN its/PRP$ hinder/VB quarters/NNS and/CC on/IN its/PRP$ forehead/NN with/IN numerous/JJ ,/, very/RB narrow/JJ ,/, dark/JJ ,/, zebra/NN like/IN bars/NNS ,/, and/CC its/PRP$ legs/NNS were/VBD feebly/RB striped/JJ :/: all/DT the/DT stripes/NNS soon/RB disappeared/VBD completely/RB ./. Without/IN here/RB entering/VBG on/IN further/JJR details/NNS ,/, I/PRP may/MD state/NN that/IN I/PRP have/VBP collected/VBN cases/NNS of/IN leg/NN and/CC shoulder/NN stripes/NNS in/IN horses/NNS of/IN very/RB different/JJ breeds/NNS in/IN various/JJ countries/NNS from/IN Britain/NNP to/TO eastern/JJ China/NNP ;/: and/CC from/IN Norway/NNP in/IN the/DT north/RB to/TO the/DT Malay/NNP Archipelago/NNP in/IN the/DT south/RB ./. In/IN all/DT parts/NNS of/IN the/DT world/NN these/DT stripes/NNS occur/VB far/RB oftenest/JJS in/IN duns/NNS and/CC mouse/NN duns/NNS ;/: by/IN the/DT term/NN dun/NN a/DT large/JJ range/NN of/IN colour/NN is/VBZ included/VBN ,/, from/IN one/CD between/IN brown/JJ and/CC black/JJ to/TO a/DT close/VB approach/NN to/TO cream/NN colour/NN ./. 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Now/RB let/VB us/PRP turn/VB to/TO the/DT effects/NNS of/IN crossing/VBG the/DT several/JJ species/NN of/IN the/DT horse/NN genus/NN ./. Rollin/NNP asserts/VBZ ,/, that/IN the/DT common/JJ mule/NN from/IN the/DT ass/NN and/CC horse/NN is/VBZ particularly/RB apt/JJ to/TO have/VB bars/NNS on/IN its/PRP$ legs/NNS ;/: according/VBG to/TO Mr/NNP ./. Gosse/NNP ,/, in/IN certain/JJ parts/NNS of/IN the/DT United/NNP States/NNPS about/IN nine/CD out/IN of/IN ten/CD mules/NNS have/VBP striped/JJ legs/NNS ./. I/PRP once/RB saw/VBD a/DT mule/NN with/IN its/PRP$ legs/NNS so/RB much/JJ striped/JJ that/IN any/DT one/CD might/MD have/VB thought/VBD that/IN it/PRP was/VBD a/DT hybrid/JJ zebra/NN ;/: and/CC Mr/NNP ./. W/NNP ./. C/NN ./. Martin/NNP ,/, in/IN his/PRP$ excellent/JJ treatise/NN on/IN the/DT horse/NN ,/, has/VBZ given/VBN a/DT figure/NN of/IN a/DT similar/JJ mule/NN ./. 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Gray/NNP (/( and/CC he/PRP informs/VBZ me/PRP that/IN he/PRP knows/VBZ of/IN a/DT second/JJ case/NN )/SYM from/IN the/DT ass/NN and/CC the/DT hemionus/JJ ;/: and/CC this/DT hybrid/JJ ,/, though/IN the/DT ass/NN only/RB occasionally/RB has/VBZ stripes/NNS on/IN its/PRP$ legs/NNS and/CC the/DT hemionus/JJ has/VBZ none/NN and/CC has/VBZ not/RB even/RB a/DT shoulder/NN stripe/NN ,/, nevertheless/RB had/VBD all/DT four/CD legs/NNS barred/VBN ,/, and/CC had/VBD three/CD short/JJ shoulder/NN stripes/NNS ,/, like/IN those/DT on/IN the/DT dun/NN Devonshire/NNP and/CC Welsh/NNP ponies/NNS ,/, and/CC even/RB had/VBD some/DT zebra/NN like/IN stripes/NNS on/IN the/DT sides/NNS of/IN its/PRP$ face/NN ./. 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He/PRP who/WP believes/VBZ that/IN each/DT equine/NN species/NN was/VBD independently/RB created/VBN ,/, will/MD ,/, I/PRP presume/VB ,/, assert/VB that/IN each/DT species/NN has/VBZ been/VBN created/VBN with/IN a/DT tendency/NN to/TO vary/VB ,/, both/DT under/IN nature/NN and/CC under/IN domestication/NN ,/, in/IN this/DT particular/JJ manner/NN ,/, so/RB as/IN often/RB to/TO become/VB striped/JJ like/IN the/DT other/JJ species/NN of/IN the/DT genus/NN ;/: and/CC that/IN each/DT has/VBZ been/VBN created/VBN with/IN a/DT strong/JJ tendency/NN ,/, when/WRB crossed/VBD with/IN species/NN inhabiting/VBG distant/JJ quarters/NNS of/IN the/DT world/NN ,/, to/TO produce/VB hybrids/NNS resembling/VBG in/IN their/PRP$ stripes/NNS ,/, not/RB their/PRP$ own/JJ parents/NNS ,/, but/CC other/JJ species/NN of/IN the/DT genus/NN ./. To/TO admit/VB this/DT view/NN is/VBZ ,/, as/IN it/PRP seems/VBZ to/TO me/PRP ,/, to/TO reject/VB a/DT real/JJ for/IN an/DT unreal/JJ ,/, or/CC at/IN least/JJS for/IN an/DT unknown/JJ ,/, cause/NN ./. It/PRP makes/VBZ the/DT works/NNS of/IN God/NNP a/DT mere/JJ mockery/NN and/CC deception/NN ;/: I/PRP would/MD almost/RB as/IN soon/RB believe/VBP ,/, with/IN the/DT old/JJ and/CC ignorant/JJ cosmogonists/NNS ,/, that/IN fossil/JJ shells/NNS had/VBD never/RB lived/VBD ,/, but/CC had/VBD been/VBN created/VBN in/IN stone/NN so/RB as/IN to/TO mock/JJ the/DT shells/NNS living/VBG on/IN the/DT seashore/NN ./. Summary/NNP ./. Our/PRP$ ignorance/NN of/IN the/DT laws/NNS of/IN variation/NN is/VBZ profound/JJ ./. Not/RB in/IN one/CD case/NN out/IN of/IN a/DT hundred/CD can/MD we/PRP pretend/VB to/TO assign/VB any/DT reason/NN why/WRB this/DT or/CC that/IN part/NN has/VBZ varied/VBN ./. But/CC whenever/WRB we/PRP have/VBP the/DT means/VBZ of/IN instituting/VBG a/DT comparison/NN ,/, the/DT same/JJ laws/NNS appear/VB to/TO have/VB acted/VBD in/IN producing/VBG the/DT lesser/JJR differences/NNS between/IN varieties/NNS of/IN the/DT same/JJ species/NN ,/, and/CC the/DT greater/JJR differences/NNS between/IN species/NN of/IN the/DT same/JJ genus/NN ./. Changed/VBN conditions/NNS generally/RB induce/VB mere/JJ fluctuating/VBG variability/NN ,/, but/CC sometimes/RB they/PRP cause/NN direct/JJ and/CC definite/JJ effects/NNS ;/: and/CC these/DT may/MD become/VB strongly/RB marked/VBN in/IN the/DT course/NN of/IN time/NN ,/, though/IN we/PRP have/VBP not/RB sufficient/JJ evidence/NN on/IN this/DT head/NN ./. 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In/IN these/DT remarks/NNS we/PRP have/VBP referred/VBN to/TO special/JJ parts/NNS or/CC organs/NNS being/VBG still/RB variable/JJ ,/, because/IN they/PRP have/VBP recently/RB varied/VBN and/CC thus/RB come/VB to/TO differ/VB ;/: but/CC we/PRP have/VBP also/RB seen/VBN in/IN the/DT second/JJ chapter/NN that/IN the/DT same/JJ principle/NN applies/VBZ to/TO the/DT whole/JJ individual/JJ ;/: for/IN in/IN a/DT district/NN where/WRB many/JJ species/NN of/IN a/DT genus/NN are/VBP found/VBD that/IN is/VBZ ,/, where/WRB there/EX has/VBZ been/VBN much/JJ former/JJ variation/NN and/CC differentiation/NN ,/, or/CC where/WRB the/DT manufactory/JJ of/IN new/JJ specific/JJ forms/NNS has/VBZ been/VBN actively/RB at/IN work/NN in/IN that/IN district/NN and/CC amongst/IN these/DT species/NN ,/, we/PRP now/RB find/VB ,/, on/IN an/DT average/JJ ,/, most/RBS varieties/NNS ./. Secondary/JJ sexual/JJ characters/NNS are/VBP highly/RB variable/JJ ,/, and/CC such/JJ characters/NNS differ/VBP much/JJ in/IN the/DT species/NN of/IN the/DT same/JJ group/NN ./. Variability/NN in/IN the/DT same/JJ parts/NNS of/IN the/DT organisation/NN has/VBZ generally/RB been/VBN taken/VBN advantage/NN of/IN in/IN giving/VBG secondary/JJ sexual/JJ differences/NNS to/TO the/DT two/CD sexes/NNS of/IN the/DT same/JJ species/NN ,/, and/CC specific/JJ differences/NNS to/TO the/DT several/JJ species/NN of/IN the/DT same/JJ genus/NN ./. 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But/CC when/WRB a/DT species/NN with/IN any/DT extraordinarily/RB developed/VBN organ/NN has/VBZ become/VB the/DT parent/NN of/IN many/JJ modified/VBN descendants/NNS which/WDT on/IN our/PRP$ view/NN must/MD be/VB a/DT very/RB slow/JJ process/NN ,/, requiring/VBG long/JJ lapse/NN of/IN time/NN in/IN this/DT case/NN ,/, natural/JJ selection/NN has/VBZ succeeded/VBN in/IN giving/VBG a/DT fixed/VBN character/NN to/TO the/DT organ/NN ,/, in/IN however/RB extraordinary/JJ a/DT manner/NN it/PRP may/MD have/VB been/VBN developed/VBN ./. Species/NNP inheriting/VBG nearly/RB the/DT same/JJ constitution/NN from/IN a/DT common/JJ parent/NN ,/, and/CC exposed/VBN to/TO similar/JJ influences/NNS ,/, naturally/RB tend/VBP to/TO present/JJ analogous/JJ variations/NNS ,/, or/CC these/DT same/JJ species/NN may/MD occasionally/RB revert/VB to/TO some/DT of/IN the/DT characters/NNS of/IN their/PRP$ ancient/JJ progenitors/NNS ./. Although/IN new/JJ and/CC important/JJ modifications/NNS may/MD not/RB arise/VB from/IN reversion/NN and/CC analogous/JJ variation/NN ,/, such/JJ modifications/NNS will/MD add/VB to/TO the/DT beautiful/JJ and/CC harmonious/JJ diversity/NN of/IN nature/NN ./. Whatever/WDT the/DT cause/NN may/MD be/VB of/IN each/DT slight/JJ difference/NN between/IN the/DT offspring/NN and/CC their/PRP$ parents/NNS and/CC a/DT cause/NN for/IN each/DT must/MD exist/VB we/PRP have/VBP reason/NN to/TO believe/VB that/IN it/PRP is/VBZ the/DT steady/JJ accumulation/NN of/IN beneficial/JJ differences/NNS which/WDT has/VBZ given/VBN rise/NN to/TO all/DT the/DT more/JJR important/JJ modifications/NNS of/IN structure/NN in/IN relation/NN to/TO the/DT habits/NNS of/IN each/DT species/NN ./. CHAPTER/NNP VI/NNP DIFFICULTIES/NNP OF/IN THE/DT THEORY/NNP LONG/NNP before/IN the/DT reader/NN has/VBZ arrived/VBN at/IN this/DT part/NN of/IN my/PRP$ work/NN ,/, a/DT crowd/NN of/IN difficulties/NNS will/MD have/VB occurred/VBD to/TO him/PRP ./. Some/DT of/IN them/PRP are/VBP so/RB serious/JJ that/IN to/TO this/DT day/NN I/PRP can/MD hardly/RB reflect/VB on/IN them/PRP without/IN being/VBG in/IN some/DT degree/NN staggered/VBD ;/: but/CC ,/, to/TO the/DT best/JJS of/IN my/PRP$ judgment/NN ,/, the/DT greater/JJR number/NN are/VBP only/RB apparent/JJ ,/, and/CC those/DT that/IN are/VBP real/JJ are/VBP not/RB ,/, I/PRP think/VBP ,/, fatal/JJ to/TO the/DT theory/NN ./. 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Can/MD we/PRP believe/VBP that/IN natural/JJ selection/NN could/MD produce/VB ,/, on/IN the/DT one/CD hand/NN ,/, an/DT organ/NN of/IN trifling/JJ importance/NN ,/, such/JJ as/IN the/DT tail/NN of/IN a/DT giraffe/NN ,/, which/WDT serves/VBZ as/IN a/DT fly/VB flapper/NN ,/, and/CC ,/, on/IN the/DT other/JJ hand/NN ,/, an/DT organ/NN so/RB wonderful/JJ as/IN the/DT eye/NN ?/. Thirdly/RB ,/, can/MD instincts/NNS be/VB acquired/VBN and/CC modified/VBN through/IN natural/JJ selection/NN ?/. What/WP shall/MD we/PRP say/VBP to/TO the/DT instinct/NN which/WDT leads/VBZ the/DT bee/NN to/TO make/VB cells/NNS ,/, and/CC which/WDT has/VBZ practically/RB anticipated/VBN the/DT discoveries/NNS of/IN profound/JJ mathematicians/NNS ?/. 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As/IN natural/JJ selection/NN acts/NNS solely/RB by/IN the/DT preservation/NN of/IN profitable/JJ modifications/NNS ,/, each/DT new/JJ form/NN will/MD tend/VB in/IN a/DT fully/RB stocked/VBN country/NN to/TO take/VB the/DT place/NN of/IN ,/, and/CC finally/RB to/TO exterminate/VB ,/, its/PRP$ own/JJ less/JJR improved/VBN parent/NN form/NN and/CC other/JJ less/JJR favoured/VBN forms/NNS with/IN which/WDT it/PRP comes/VBZ into/IN competition/NN ./. Thus/RB extinction/NN and/CC natural/JJ selection/NN go/VB hand/NN in/IN hand/NN ./. Hence/RB ,/, if/IN we/PRP look/VB at/IN each/DT species/NN as/IN descended/VBD from/IN some/DT unknown/JJ form/NN ,/, both/DT the/DT parent/NN and/CC all/DT the/DT transitional/JJ varieties/NNS will/MD generally/RB have/VBP been/VBN exterminated/VBN by/IN the/DT very/RB process/NN of/IN the/DT formation/NN and/CC perfection/NN of/IN the/DT new/JJ form/NN ./. 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But/CC it/PRP may/MD be/VB urged/VBD that/IN when/WRB several/JJ closely/RB allied/VBN species/NN inhabit/VBP the/DT same/JJ territory/NN ,/, we/PRP surely/RB ought/MD to/TO find/VB at/IN the/DT present/JJ time/NN many/JJ transitional/JJ forms/NNS ./. Let/VB us/PRP take/VB a/DT simple/JJ case/NN :/: in/IN travelling/VBG from/IN north/RB to/TO south/RB over/IN a/DT continent/NN ,/, we/PRP generally/RB meet/VB at/IN successive/JJ intervals/NNS with/IN closely/RB allied/VBN or/CC representative/NN species/NN ,/, evidently/RB filling/VBG nearly/RB the/DT same/JJ place/NN in/IN the/DT natural/JJ economy/NN of/IN the/DT land/NN ./. These/DT representative/NN species/NN often/RB meet/VB and/CC interlock/NN ;/: and/CC as/IN the/DT one/CD becomes/VBZ rarer/JJR and/CC rarer/JJR ,/, the/DT other/JJ becomes/VBZ more/JJR and/CC more/JJR frequent/JJ ,/, till/IN the/DT one/CD replaces/VBZ the/DT other/JJ ./. But/CC if/IN we/PRP compare/VB these/DT species/NN where/WRB they/PRP intermingle/VBP ,/, they/PRP are/VBP generally/RB as/IN absolutely/RB distinct/JJ from/IN each/DT other/JJ in/IN every/DT detail/NN of/IN structure/NN as/IN are/VBP specimens/NNS taken/VBN from/IN the/DT metropolis/NN inhabited/VBN by/IN each/DT ./. By/IN my/PRP$ theory/NN these/DT allied/VBN species/NN are/VBP descended/VBD from/IN a/DT common/JJ parent/NN ;/: and/CC during/IN the/DT process/NN of/IN modification/NN ,/, each/DT has/VBZ become/VB adapted/VBN to/TO the/DT conditions/NNS of/IN life/NN of/IN its/PRP$ own/JJ region/NN ,/, and/CC has/VBZ supplanted/VBN and/CC exterminated/VBN its/PRP$ original/JJ parent/NN form/NN and/CC all/DT the/DT transitional/JJ varieties/NNS between/IN its/PRP$ past/JJ and/CC present/JJ states/NNS ./. Hence/RB we/PRP ought/MD not/RB to/TO expect/VB at/IN the/DT present/JJ time/NN to/TO meet/VB with/IN numerous/JJ transitional/JJ varieties/NNS in/IN each/DT region/NN ,/, though/IN they/PRP must/MD have/VB existed/VBD there/EX ,/, and/CC may/MD be/VB embedded/VBN there/EX in/IN a/DT fossil/JJ condition/NN ./. But/CC in/IN the/DT intermediate/JJ region/NN ,/, having/VBG intermediate/JJ conditions/NNS of/IN life/NN ,/, why/WRB do/VBP we/PRP not/RB now/RB find/VB closely/RB linking/VBG intermediate/JJ varieties/NNS ?/. This/DT difficulty/NN for/IN a/DT long/JJ time/NN quite/RB confounded/VBD me/PRP ./. But/CC I/PRP think/VBP it/PRP can/MD be/VB in/IN large/JJ part/NN explained/VBD ./. In/IN the/DT first/JJ place/NN we/PRP should/MD be/VB extremely/RB cautious/JJ in/IN inferring/VBG ,/, because/IN an/DT area/NN is/VBZ now/RB continuous/JJ ,/, that/IN it/PRP has/VBZ been/VBN continuous/JJ during/IN a/DT long/JJ period/NN ./. Geology/NNP would/MD lead/VB us/PRP to/TO believe/VB that/IN most/RBS continents/NNS have/VBP been/VBN broken/VBN up/IN into/IN islands/NNS even/RB during/IN the/DT later/RB tertiary/JJ periods/NNS ;/: and/CC in/IN such/JJ islands/NNS distinct/JJ species/NN might/MD have/VB been/VBN separately/RB formed/VBN without/IN the/DT possibility/NN of/IN intermediate/JJ varieties/NNS existing/VBG in/IN the/DT intermediate/JJ zones/NNS ./. By/IN changes/NNS in/IN the/DT form/NN of/IN the/DT land/NN and/CC of/IN climate/NN ,/, marine/NN areas/NNS now/RB continuous/JJ must/MD often/RB have/VBP existed/VBD within/IN recent/JJ times/NNS in/IN a/DT far/RB less/JJR continuous/JJ and/CC uniform/NN condition/NN than/IN at/IN present/JJ ./. 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Hence/RB the/DT neutral/JJ territory/NN between/IN two/CD representative/NN species/NN is/VBZ generally/RB narrow/JJ in/IN comparison/NN with/IN the/DT territory/NN proper/JJ to/TO each/DT ./. We/PRP see/VB the/DT same/JJ fact/NN in/IN ascending/VBG mountains/NNS ,/, and/CC sometimes/RB it/PRP is/VBZ quite/RB remarkable/JJ how/WRB abruptly/RB ,/, as/IN Alph/NNP ./. de/FW Candolle/NNP has/VBZ observed/VBN ,/, a/DT common/JJ alpine/NN species/NN disappears/VBZ ./. The/DT same/JJ fact/NN has/VBZ been/VBN noticed/VBD by/IN E/NN ./. Forbes/NNP in/IN sounding/VBG the/DT depths/NNS of/IN the/DT sea/NN with/IN the/DT dredge/NN ./. To/TO those/DT who/WP look/VB at/IN climate/NN and/CC the/DT physical/JJ conditions/NNS of/IN life/NN as/IN the/DT all/DT important/JJ elements/NNS of/IN distribution/NN ,/, these/DT facts/NNS ought/MD to/TO cause/NN surprise/NN ,/, as/IN climate/NN and/CC height/NN or/CC depth/NN graduate/NN away/RB insensibly/RB ./. 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I/PRP may/MD illustrate/VB what/WP I/PRP mean/VB by/IN supposing/VBG three/CD varieties/NNS of/IN sheep/NN to/TO be/VB kept/VBD ,/, one/CD adapted/VBN to/TO an/DT extensive/JJ mountainous/JJ region/NN ;/: a/DT second/JJ to/TO a/DT comparatively/RB narrow/JJ ,/, hilly/JJ tract/NN ;/: and/CC a/DT third/JJ to/TO the/DT wide/JJ plains/NNS at/IN the/DT base/NN ;/: and/CC that/IN the/DT inhabitants/NNS are/VBP all/DT trying/VBG with/IN equal/JJ steadiness/NN and/CC skill/NN to/TO improve/VB their/PRP$ stocks/NNS by/IN selection/NN ;/: the/DT chances/NNS in/IN this/DT case/NN will/MD be/VB strongly/RB in/IN favour/NN of/IN the/DT great/JJ holders/NNS on/IN the/DT mountains/NNS or/CC on/IN the/DT plains/NNS ,/, improving/VBG their/PRP$ breeds/NNS more/JJR quickly/RB than/IN the/DT small/JJ holders/NNS on/IN the/DT intermediate/JJ narrow/JJ ,/, hilly/JJ tract/NN ;/: and/CC consequently/RB the/DT improved/VBN mountain/NN or/CC plain/JJ breed/NN will/MD soon/RB take/VB the/DT place/NN of/IN the/DT less/JJR improved/VBN hill/NN breed/NN ;/: and/CC thus/RB the/DT two/CD breeds/NNS ,/, which/WDT originally/RB existed/VBD in/IN greater/JJR numbers/NNS ,/, will/MD come/VB into/IN close/VB contact/NN with/IN each/DT other/JJ ,/, without/IN the/DT interposition/NN of/IN the/DT supplanted/VBN ,/, intermediate/JJ hill/NN variety/NN ./. 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Secondly/RB ,/, areas/NNS now/RB continuous/JJ must/MD often/RB have/VBP existed/VBD within/IN the/DT recent/JJ period/NN as/IN isolated/VBN portions/NNS ,/, in/IN which/WDT many/JJ forms/NNS ,/, more/JJR especially/RB amongst/IN the/DT classes/NNS which/WDT unite/VB for/IN each/DT birth/NN and/CC wander/VB much/JJ ,/, may/MD have/VB separately/RB been/VBN rendered/VBN sufficiently/RB distinct/JJ to/TO rank/NN as/IN representative/NN species/NN ./. In/IN this/DT ,/, case/NN ,/, intermediate/JJ varieties/NNS between/IN the/DT several/JJ representative/NN species/NN and/CC their/PRP$ common/JJ parent/NN ,/, must/MD formerly/RB have/VBP existed/VBD within/IN each/DT isolated/VBN portion/NN of/IN the/DT land/NN ,/, but/CC these/DT links/NNS during/IN the/DT process/NN of/IN natural/JJ selection/NN will/MD have/VB been/VBN supplanted/VBN and/CC exterminated/VBN ,/, so/RB that/IN they/PRP will/MD no/DT longer/RB be/VB found/VBD in/IN a/DT living/VBG state/NN ./. 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Nor/CC can/MD I/PRP see/VB any/DT insuperable/JJ difficulty/NN in/IN further/JJR believing/VBG that/IN the/DT membrane/NN connected/VBN fingers/NNS and/CC fore/NN arm/NN of/IN the/DT Galeopithecus/NNP might/MD have/VB been/VBN greatly/RB lengthened/VBN by/IN natural/JJ selection/NN ;/: and/CC this/DT ,/, as/IN far/RB as/IN the/DT organs/NNS of/IN flight/NN are/VBP concerned/VBN ,/, would/MD have/VB converted/VBN the/DT animal/NN into/IN a/DT bat/NN ./. In/IN certain/JJ bats/NNS in/IN which/WDT the/DT wing/NN membrane/NN extends/VBZ from/IN the/DT top/JJ of/IN the/DT shoulder/NN to/TO the/DT tail/NN and/CC includes/VBZ the/DT hind/JJ legs/NNS ,/, we/PRP perhaps/RB see/VB traces/NNS of/IN an/DT apparatus/NN originally/RB fitted/VBN for/IN gliding/VBG through/IN the/DT air/NN rather/RB than/IN for/IN flight/NN ./. 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It/PRP must/MD not/RB be/VB inferred/VBD from/IN these/DT remarks/NNS that/IN any/DT of/IN the/DT grades/NNS of/IN wing/NN structure/NN here/RB alluded/VBD to/TO ,/, which/WDT perhaps/RB may/MD all/DT be/VB the/DT result/NN of/IN disuse/NN ,/, indicate/VB the/DT steps/NNS by/IN which/WDT birds/NNS actually/RB acquired/VBN their/PRP$ perfect/JJ power/NN of/IN flight/NN ;/: but/CC they/PRP serve/VB to/TO show/NN what/WP diversified/JJ means/VBZ of/IN transition/NN are/VBP at/IN least/JJS possible/JJ ./. Seeing/VBG that/IN a/DT few/JJ members/NNS of/IN such/JJ water/NN breathing/NN classes/NNS as/IN the/DT Crustacea/NNP and/CC Mollusca/NNP are/VBP adapted/VBN to/TO live/VB on/IN the/DT land/NN ;/: and/CC seeing/VBG that/IN we/PRP have/VBP flying/VBG birds/NNS and/CC mammals/NNS ,/, flying/VBG insects/NNS of/IN the/DT most/RBS diversified/JJ types/NNS ,/, and/CC formerly/RB had/VBD flying/VBG reptiles/NNS ,/, it/PRP is/VBZ conceivable/JJ that/IN flying/VBG fish/NN ,/, which/WDT now/RB glide/VB far/RB through/IN the/DT air/NN ,/, slightly/RB rising/VBG and/CC turning/VBG by/IN the/DT aid/NN of/IN their/PRP$ fluttering/VBG fins/NNS ,/, might/MD have/VB been/VBN modified/VBN into/IN perfectly/RB winged/VBD animals/NNS ./. If/IN this/DT had/VBD been/VBN effected/VBN ,/, who/WP would/MD have/VB ever/RB imagined/VBN that/IN in/IN an/DT early/JJ transitional/JJ state/NN they/PRP had/VBD been/VBN the/DT inhabitants/NNS of/IN the/DT open/JJ ocean/NN ,/, and/CC had/VBD used/VBN their/PRP$ incipient/JJ organs/NNS of/IN flight/NN exclusively/RB ,/, as/IN far/RB as/IN we/PRP know/VB ,/, to/TO escape/VB being/VBG devoured/VBN by/IN other/JJ fish/NN ?/. 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It/PRP is/VBZ ,/, however/RB ,/, difficult/JJ to/TO decide/VB ,/, and/CC immaterial/JJ for/IN us/PRP ,/, whether/IN habits/NNS generally/RB change/NN first/JJ and/CC structure/NN afterwards/RB ;/: or/CC whether/IN slight/JJ modifications/NNS of/IN structure/NN lead/VB to/TO changed/VBN habits/NNS ;/: both/DT probably/RB often/RB occurring/VBG almost/RB simultaneously/RB ./. Of/IN cases/NNS of/IN changed/VBN habits/NNS it/PRP will/MD suffice/VB merely/RB to/TO allude/NN to/TO that/IN of/IN the/DT many/JJ British/JJ insects/NNS which/WDT now/RB feed/NN on/IN exotic/JJ plants/NNS ,/, or/CC exclusively/RB on/IN artificial/JJ substances/NNS ./. Of/IN diversified/JJ habits/NNS innumerable/JJ instances/NNS could/MD be/VB given/VBN :/: I/PRP have/VBP often/RB watched/VBD a/DT tyrant/NN flycatcher/NN (/( Saurophagus/NNP sulphuratus/JJ )/SYM in/IN South/NNP America/NNP ,/, hovering/VBG over/IN one/CD spot/NN and/CC then/RB proceeding/NN to/TO another/DT ,/, like/IN a/DT kestrel/NN ,/, and/CC at/IN other/JJ times/NNS standing/VBG stationary/JJ on/IN the/DT margin/NN of/IN water/NN ,/, and/CC then/RB dashing/VBG into/IN it/PRP like/IN a/DT kingfisher/NN at/IN a/DT fish/NN ./. In/IN our/PRP$ own/JJ country/NN the/DT larger/JJR titmouse/NN (/( Parus/NNP major/JJ )/SYM may/MD be/VB seen/VBN climbing/VBG branches/NNS ,/, almost/RB like/IN a/DT creeper/NN ;/: it/PRP sometimes/RB ,/, like/IN a/DT shrike/NN ,/, kills/VBZ small/JJ birds/NNS by/IN blows/NNS on/IN the/DT head/NN ;/: and/CC I/PRP have/VBP many/JJ times/NNS seen/VBN and/CC heard/VBN it/PRP hammering/VBG the/DT seeds/NNS of/IN the/DT yew/NN on/IN a/DT branch/NN ,/, and/CC thus/RB breaking/VBG them/PRP like/IN a/DT nuthatch/NN ./. In/IN North/NNP America/NNP the/DT black/JJ bear/VB was/VBD seen/VBN by/IN Hearne/NNP swimming/VBG for/IN hours/NNS with/IN widely/RB open/JJ mouth/NN ,/, thus/RB catching/VBG ,/, almost/RB like/IN a/DT whale/NN ,/, insects/NNS in/IN the/DT water/NN ./. 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Hence/RB this/DT Colaptes/NNP in/IN all/DT the/DT essential/JJ parts/NNS of/IN its/PRP$ structure/NN is/VBZ a/DT woodpecker/NN ./. Even/RB in/IN such/JJ trifling/JJ characters/NNS as/IN the/DT colouring/VBG ,/, the/DT harsh/JJ tone/NN of/IN the/DT voice/NN ,/, and/CC undulatory/JJ flight/NN ,/, its/PRP$ close/VB blood/NN relationship/NN to/TO our/PRP$ common/JJ woodpecker/NN is/VBZ plainly/RB declared/VBD ;/: yet/RB ,/, as/IN I/PRP can/MD assert/VB ,/, not/RB only/RB from/IN my/PRP$ own/JJ observation/NN ,/, but/CC from/IN those/DT of/IN the/DT accurate/JJ Azara/NNP ,/, in/IN certain/JJ large/JJ districts/NNS it/PRP does/VBZ not/RB climb/VB trees/NNS ,/, and/CC it/PRP makes/VBZ its/PRP$ nest/NN in/IN holes/NNS in/IN banks!/NN In/IN certain/JJ other/JJ districts/NNS ,/, however/RB ,/, this/DT same/JJ woodpecker/NN ,/, as/IN Mr/NNP ./. Hudson/NNP states/NNS ,/, frequents/VBZ trees/NNS ,/, and/CC bores/NNS holes/NNS in/IN the/DT trunk/NN for/IN its/PRP$ nest/NN ./. 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In/IN the/DT case/NN of/IN the/DT waterouzel/NN ,/, the/DT acutest/JJS observer/NN by/IN examining/VBG its/PRP$ dead/JJ body/NN would/MD never/RB have/VBP suspected/VBN its/PRP$ subaquatic/JJ habits/NNS ;/: yet/RB this/DT bird/NN ,/, which/WDT is/VBZ allied/VBN to/TO the/DT thrush/NN family/NN ,/, subsists/NNS by/IN diving/VBG using/VBG its/PRP$ wings/NNS under/IN water/NN ,/, and/CC grasping/VBG stones/NNS with/IN its/PRP$ feet/NNS ./. 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Reason/NNP tells/VBZ me/PRP ,/, that/IN if/IN numerous/JJ gradations/NNS from/IN a/DT simple/JJ and/CC imperfect/JJ eye/NN to/TO one/CD complex/JJ and/CC perfect/JJ can/MD be/VB shown/VBN to/TO exist/VB ,/, each/DT grade/NN being/VBG useful/JJ to/TO its/PRP$ possessor/NN ,/, as/IN is/VBZ certainly/RB the/DT case/NN ;/: if/IN further/JJR ,/, the/DT eye/NN ever/RB varies/VBZ and/CC the/DT variations/NNS be/VB inherited/VBN ,/, as/IN is/VBZ likewise/RB certainly/RB the/DT case/NN and/CC if/IN such/JJ variations/NNS should/MD be/VB useful/JJ to/TO any/DT animal/NN under/IN changing/VBG conditions/NNS of/IN life/NN ,/, then/RB the/DT difficulty/NN of/IN believing/VBG that/IN a/DT perfect/JJ and/CC complex/JJ eye/NN could/MD be/VB formed/VBN by/IN natural/JJ selection/NN ,/, though/IN insuperable/JJ by/IN our/PRP$ imagination/NN ,/, should/MD not/RB be/VB considered/VBN as/IN subversive/JJ of/IN the/DT theory/NN ./. How/WRB a/DT nerve/NN comes/VBZ to/TO be/VB sensitive/JJ to/TO light/NN ,/, hardly/RB concerns/NNS us/PRP more/JJR than/IN how/WRB life/NN itself/PRP originated/VBD ;/: but/CC I/PRP may/MD remark/NN that/IN ,/, as/IN some/DT of/IN the/DT lowest/JJS organisms/NNS ,/, in/IN which/WDT nerves/NNS cannot/MD be/VB detected/VBN ,/, are/VBP capable/JJ of/IN perceiving/VBG light/NN ,/, it/PRP does/VBZ not/RB seem/VB impossible/JJ that/IN certain/JJ sensitive/JJ elements/NNS in/IN their/PRP$ sarcode/NN should/MD become/VB aggregated/VBN and/CC developed/VBN into/IN nerves/NNS ,/, endowed/VBN with/IN this/DT special/JJ sensibility/NN ./. In/IN searching/VBG for/IN the/DT gradations/NNS through/IN which/WDT an/DT orgain/NN in/IN any/DT species/NN has/VBZ been/VBN perfected/VBN ,/, we/PRP ought/MD to/TO look/VB exclusively/RB to/TO its/PRP$ lineal/JJ progenitors/NNS ;/: but/CC this/DT is/VBZ scarcely/RB ever/RB possible/JJ ,/, and/CC we/PRP are/VBP forced/VBN to/TO look/VB to/TO other/JJ species/NN and/CC genera/NN of/IN the/DT same/JJ group/NN ,/, that/IN is/VBZ to/TO the/DT collateral/NN descendants/NNS from/IN the/DT same/JJ parent/NN form/NN ,/, in/IN order/NN to/TO see/VB what/WP gradations/NNS are/VBP possible/JJ ,/, and/CC for/IN the/DT chance/NN of/IN some/DT gradations/NNS having/VBG been/VBN transmitted/VBN in/IN an/DT unaltered/JJ or/CC little/JJ altered/VBN condition/NN ./. But/CC the/DT state/NN of/IN the/DT same/JJ organ/NN in/IN distinct/JJ classes/NNS may/MD incidentally/RB throw/VB light/NN on/IN the/DT steps/NNS by/IN which/WDT it/PRP has/VBZ been/VBN perfected/VBN ./. The/DT simplest/JJS organ/NN which/WDT can/MD be/VB called/VBN an/DT eye/NN consists/VBZ of/IN an/DT optic/JJ nerve/NN ,/, surrounded/VBN by/IN pigment/NN cells/NNS ,/, and/CC covered/VBN by/IN translucent/JJ skin/NN ,/, but/CC without/IN any/DT lens/NN or/CC other/JJ refractive/JJ body/NN ./. We/PRP may/MD ,/, however/RB ,/, according/VBG to/TO M/NNP ./. Jourdain/NNP ,/, descend/VB even/RB a/DT step/NN lower/JJR and/CC find/VB aggregates/NNS of/IN pigment/NN cells/NNS ,/, apparently/RB serving/VBG as/IN organs/NNS of/IN vision/NN ,/, without/IN any/DT nerves/NNS ,/, and/CC resting/VBG merely/RB on/IN sarcodic/JJ tissue/NN ./. Eyes/NNP of/IN the/DT above/IN simple/JJ nature/NN are/VBP not/RB capable/JJ of/IN distinct/JJ vision/NN ,/, and/CC serve/VB only/RB to/TO distinguish/VB light/NN from/IN darkness/NN ./. In/IN certain/JJ star/NN fishes/NNS ,/, small/JJ depressions/NNS in/IN the/DT layer/NN of/IN pigment/NN which/WDT surrounds/VBZ the/DT nerve/NN are/VBP filled/VBN ,/, as/IN described/VBN by/IN the/DT author/NN just/RB quoted/VBN ,/, with/IN transparent/JJ gelatinous/JJ matter/NN ,/, projecting/VBG with/IN a/DT convex/JJ surface/NN ,/, like/IN the/DT cornea/NN in/IN the/DT higher/JJR animals/NNS ./. He/PRP suggests/VBZ that/IN this/DT serves/VBZ not/RB to/TO form/NN an/DT image/NN ,/, but/CC only/RB to/TO concentrate/VB the/DT luminous/JJ rays/NNS and/CC render/VB their/PRP$ perception/NN more/JJR easy/JJ ./. In/IN this/DT concentration/NN of/IN the/DT rays/NNS we/PRP gain/NN the/DT first/JJ and/CC by/IN far/RB the/DT most/RBS important/JJ step/NN towards/IN the/DT formation/NN of/IN a/DT true/JJ ,/, picture/NN forming/VBG eye/NN ;/: for/IN we/PRP have/VBP only/RB to/TO place/NN the/DT naked/JJ extremity/NN of/IN the/DT optic/JJ nerve/NN ,/, which/WDT in/IN some/DT of/IN the/DT lower/JJR animals/NNS lies/VBZ deeply/RB buried/VBN in/IN the/DT body/NN ,/, and/CC in/IN some/DT near/IN the/DT surface/NN ,/, at/IN the/DT right/NN distance/NN from/IN the/DT concentrating/VBG apparatus/NN ,/, and/CC an/DT image/NN will/MD be/VB formed/VBN on/IN it/PRP ./. In/IN the/DT great/JJ class/NN of/IN the/DT Articulata/NNP ,/, we/PRP may/MD start/VB from/IN an/DT optic/JJ nerve/NN simply/RB coated/VBN with/IN pigment/NN ,/, the/DT latter/NN sometimes/RB forming/VBG a/DT sort/NN of/IN pupil/NN ,/, but/CC destitute/JJ of/IN a/DT lens/NN or/CC other/JJ optical/JJ contrivance/NN ./. With/IN insects/NNS it/PRP is/VBZ now/RB known/VBN that/IN the/DT numerous/JJ facets/NNS on/IN the/DT cornea/NN of/IN their/PRP$ great/JJ compound/NN eyes/NNS form/NN true/JJ lenses/NNS ,/, and/CC that/IN the/DT cones/NNS include/VBP curiously/RB modified/VBN nervous/JJ filaments/NNS ./. But/CC these/DT organs/NNS in/IN the/DT Articulata/NNP are/VBP so/RB much/JJ diversified/JJ that/IN Muller/NNP formerly/RB made/VBN three/CD main/JJ classes/NNS with/IN seven/CD subdivisions/NNS ,/, besides/IN a/DT fourth/JJ main/JJ class/NN of/IN aggregated/VBN simple/JJ eyes/NNS ./. When/WRB we/PRP reflect/VB on/IN these/DT facts/NNS ,/, here/RB given/VBN much/JJ too/RB briefly/NN ,/, with/IN respect/NN to/TO the/DT wide/JJ ,/, diversified/JJ ,/, and/CC graduated/VBN range/NN of/IN structure/NN in/IN the/DT eyes/NNS of/IN the/DT lower/JJR animals/NNS ;/: and/CC when/WRB we/PRP bear/VB in/IN mind/NN how/WRB small/JJ the/DT number/NN of/IN all/DT living/VBG forms/NNS must/MD be/VB in/IN comparison/NN with/IN those/DT which/WDT have/VBP become/VB extinct/JJ ,/, the/DT difficulty/NN ceases/VBZ to/TO be/VB very/RB great/JJ in/IN believing/VBG that/IN natural/JJ selection/NN may/MD have/VB converted/VBN the/DT simple/JJ apparatus/NN of/IN an/DT optic/JJ nerve/NN ,/, coated/VBN with/IN pigment/NN and/CC invested/VBN by/IN transparent/JJ membrane/NN ,/, into/IN an/DT optical/JJ instrument/NN as/IN perfect/JJ as/IN is/VBZ possessed/VBN by/IN any/DT member/NN of/IN the/DT articulate/JJ class/NN ./. He/PRP who/WP will/MD go/VB thus/RB far/RB ,/, ought/MD not/RB to/TO hesitate/VB to/TO go/VB one/CD step/NN further/JJR ,/, if/IN he/PRP finds/VBZ on/IN finishing/VBG this/DT volume/NN that/IN large/JJ bodies/NNS of/IN facts/NNS ,/, otherwise/RB inexplicable/JJ ,/, can/MD be/VB explained/VBD by/IN the/DT theory/NN of/IN modification/NN through/IN natural/JJ selection/NN ;/: he/PRP ought/MD to/TO admit/VB that/IN a/DT structure/NN even/RB as/IN perfect/JJ as/IN an/DT eagle's/NNS eye/NN might/MD thus/RB be/VB formed/VBN ,/, although/IN in/IN this/DT case/NN he/PRP does/VBZ not/RB know/VB the/DT transitional/JJ states/NNS ./. It/PRP has/VBZ been/VBN objected/VBD that/IN in/IN order/NN to/TO modify/VB the/DT eye/NN and/CC still/RB preserve/VB it/PRP as/IN a/DT perfect/JJ instrument/NN ,/, many/JJ changes/NNS would/MD have/VB to/TO be/VB effected/VBN simultaneously/RB ,/, which/WDT ,/, it/PRP is/VBZ assumed/VBN ,/, could/MD not/RB be/VB done/VBN through/IN natural/JJ selection/NN ;/: but/CC as/IN I/PRP have/VBP attempted/VBD to/TO show/NN in/IN my/PRP$ work/NN on/IN the/DT variation/NN of/IN domestic/JJ animals/NNS ,/, it/PRP is/VBZ not/RB necessary/JJ to/TO suppose/VB that/IN the/DT modifications/NNS were/VBD all/DT simultaneous/JJ ,/, if/IN they/PRP were/VBD extremely/RB slight/JJ and/CC gradual/JJ ./. Different/JJ kinds/NNS of/IN modification/NN would/MD ,/, also/RB ,/, serve/VB for/IN the/DT same/JJ general/JJ purpose/NN :/: as/IN Mr/NNP ./. Wallace/NNP has/VBZ remarked/VBN ,/, "/" if/IN a/DT lens/NN has/VBZ too/RB short/JJ or/CC too/RB long/JJ a/DT focus/NN ,/, it/PRP may/MD be/VB amended/VBN either/DT by/IN an/DT alteration/NN of/IN curvature/NN ,/, or/CC an/DT alteration/NN of/IN density/NN ;/: if/IN the/DT curvature/NN be/VB irregular/JJ ,/, and/CC the/DT rays/NNS do/VBP not/RB converge/VB to/TO a/DT point/NN ,/, then/RB any/DT increased/VBN regularity/NN of/IN curvature/NN will/MD be/VB an/DT improvement/NN ./. So/RB the/DT contraction/NN of/IN the/DT iris/NN and/CC the/DT muscular/JJ movements/NNS of/IN the/DT eye/NN are/VBP neither/DT of/IN them/PRP essential/JJ to/TO vision/NN ,/, but/CC only/RB improvements/NNS which/WDT might/MD have/VB been/VBN added/VBD and/CC perfected/VBN at/IN any/DT stage/NN of/IN the/DT construction/NN of/IN the/DT instrument/NN ./. "/" Within/IN the/DT highest/JJS division/NN of/IN the/DT animal/NN kingdom/NN ,/, namely/RB ,/, the/DT Vertebrata/NNP ,/, we/PRP can/MD start/VB from/IN an/DT eye/NN so/RB simple/JJ ,/, that/IN it/PRP consists/VBZ ,/, as/IN in/IN the/DT lancelet/NN ,/, of/IN a/DT little/JJ sack/NN of/IN transparent/JJ skin/NN ,/, furnished/VBN with/IN a/DT nerve/NN and/CC lined/VBN with/IN pigment/NN ,/, but/CC destitute/JJ of/IN any/DT other/JJ apparatus/NN ./. In/IN fishes/NNS and/CC reptiles/NNS ,/, as/IN Owen/NNP has/VBZ remarked/VBN ,/, "/" the/DT range/NN of/IN gradations/NNS of/IN dioptric/JJ structures/NNS is/VBZ very/RB great/JJ ./. "/" It/PRP is/VBZ a/DT significant/JJ fact/NN that/IN even/RB in/IN man/NN ,/, according/VBG to/TO the/DT high/JJ authority/NN of/IN Virchow/NNP ,/, the/DT beautiful/JJ crystalline/JJ lens/NN is/VBZ formed/VBN in/IN the/DT embryo/NN by/IN an/DT accumulation/NN of/IN epidermic/JJ cells/NNS ,/, lying/VBG in/IN a/DT sack/NN like/IN fold/VB of/IN the/DT skin/NN ;/: and/CC the/DT vitreous/JJ body/NN is/VBZ formed/VBN from/IN embryonic/JJ sub/NN cutaneous/JJ tissue/NN ./. To/TO arrive/VB ,/, however/RB ,/, at/IN a/DT just/RB conclusion/NN regarding/VBG the/DT formation/NN of/IN the/DT eye/NN ,/, with/IN all/DT its/PRP$ marvellous/JJ yet/RB not/RB absolutely/RB perfect/JJ characters/NNS ,/, it/PRP is/VBZ indispensable/JJ that/IN the/DT reason/NN should/MD conquer/VB the/DT imagination/NN ;/: but/CC I/PRP have/VBP felt/VBD the/DT difficulty/NN far/RB too/RB keenly/RB to/TO be/VB surprised/VBN at/IN others/NNS hesitating/VBG to/TO extend/VB the/DT principle/NN of/IN natural/JJ selection/NN to/TO so/RB startling/JJ a/DT length/NN ./. It/PRP is/VBZ scarcely/RB possible/JJ to/TO avoid/VB comparing/VBG the/DT eye/NN with/IN a/DT telescope/NN ./. We/PRP know/VB that/IN this/DT instrument/NN has/VBZ been/VBN perfected/VBN by/IN the/DT long/JJ continued/VBD efforts/NNS of/IN the/DT highest/JJS human/JJ intellects/NNS ;/: and/CC we/PRP naturally/RB infer/VB that/IN the/DT eye/NN has/VBZ been/VBN formed/VBN by/IN a/DT somewhat/RB analogous/JJ process/NN ./. But/CC may/MD not/RB this/DT inference/NN be/VB presumptuous/JJ ?/. Have/VBP we/PRP any/DT right/NN to/TO assume/VB that/IN the/DT Creator/NNP works/NNS by/IN intellectual/JJ powers/NNS like/IN those/DT of/IN man/NN ?/. If/IN we/PRP must/MD compare/VB the/DT eye/NN to/TO an/DT optical/JJ instrument/NN ,/, we/PRP ought/MD in/IN imagination/NN to/TO take/VB a/DT thick/JJ layer/NN of/IN transparent/JJ tissue/NN ,/, with/IN spaces/NNS filled/VBN with/IN fluid/NN ,/, and/CC with/IN a/DT nerve/NN sensitive/JJ to/TO light/NN beneath/IN ,/, and/CC then/RB suppose/VBP every/DT part/NN of/IN this/DT layer/NN to/TO be/VB continually/RB changing/VBG slowly/RB in/IN density/NN ,/, so/RB as/IN to/TO separate/JJ into/IN layers/NNS of/IN different/JJ densities/NNS and/CC thicknesses/NNS ,/, placed/VBN at/IN different/JJ distances/NNS from/IN each/DT other/JJ ,/, and/CC with/IN the/DT surfaces/NNS of/IN each/DT layer/NN slowly/RB changing/VBG in/IN form/NN ./. Further/RB we/PRP must/MD suppose/VB that/IN there/EX is/VBZ a/DT power/NN ,/, represented/VBN by/IN natural/JJ selection/NN or/CC the/DT survival/NN of/IN the/DT fittest/JJS ,/, always/RB intently/RB watching/VBG each/DT slight/JJ alteration/NN in/IN the/DT transparent/JJ layers/NNS ;/: and/CC carefully/RB preserving/VBG each/DT which/WDT ,/, under/IN varied/VBN circumstances/NNS ,/, in/IN any/DT way/NN or/CC in/IN any/DT degree/NN ,/, tends/VBZ to/TO produce/VB a/DT distincter/NN image/NN ./. We/PRP must/MD suppose/VB each/DT new/JJ state/NN of/IN the/DT instrument/NN to/TO be/VB multiplied/VBN by/IN the/DT million/CD ;/: each/DT to/TO be/VB preserved/VBN until/IN a/DT better/JJR one/CD is/VBZ produced/VBN ,/, and/CC then/RB the/DT old/JJ ones/NNS to/TO be/VB all/DT destroyed/VBN ./. In/IN living/VBG bodies/NNS ,/, variation/NN will/MD cause/NN the/DT slight/JJ alterations/NNS ,/, generation/NN will/MD multiply/VB them/PRP almost/RB infinitely/RB ,/, and/CC natural/JJ selection/NN will/MD pick/VB out/IN with/IN unerring/JJ skill/NN each/DT improvement/NN ./. Let/VB this/DT process/NN go/VB on/IN for/IN millions/NNS of/IN years/NNS ;/: and/CC during/IN each/DT year/NN on/IN millions/NNS of/IN individuals/NNS of/IN many/JJ kinds/NNS ;/: and/CC may/MD we/PRP not/RB believe/VBP that/IN a/DT living/VBG optical/JJ instrument/NN might/MD thus/RB be/VB formed/VBN as/IN superior/JJ to/TO one/CD of/IN glass/NN ,/, as/IN the/DT works/NNS of/IN the/DT Creator/NNP are/VBP to/TO those/DT of/IN man/NN ?/. Modes/NNP of/IN Transition/NN If/IN it/PRP could/MD be/VB demonstrated/VBN that/IN any/DT complex/JJ organ/NN existed/VBD ,/, which/WDT could/MD not/RB possibly/RB have/VBP been/VBN formed/VBN by/IN numerous/JJ ,/, successive/JJ ,/, slight/JJ modifications/NNS ,/, my/PRP$ theory/NN would/MD absolutely/RB break/VB down/RB ./. But/CC I/PRP can/MD find/VB out/IN no/DT such/JJ case/NN ./. No/DT doubt/NN many/JJ organs/NNS exist/VB of/IN which/WDT we/PRP do/VBP not/RB know/VB the/DT transitional/JJ grades/NNS ,/, more/JJR especially/RB if/IN we/PRP look/VB to/TO much/JJ isolated/VBN species/NN ,/, round/NN which/WDT ,/, according/VBG to/TO the/DT theory/NN ,/, there/EX has/VBZ been/VBN much/JJ extinction/NN ./. Or/CC again/RB ,/, if/IN we/PRP take/VB an/DT organ/NN common/JJ to/TO all/DT the/DT members/NNS of/IN a/DT class/NN ,/, for/IN in/IN this/DT latter/NN case/NN the/DT organ/NN must/MD have/VB been/VBN originally/RB formed/VBN at/IN a/DT remote/JJ period/NN ,/, since/IN which/WDT all/DT the/DT many/JJ members/NNS of/IN the/DT class/NN have/VBP been/VBN developed/VBN ;/: and/CC in/IN order/NN to/TO discover/VB the/DT early/JJ transitional/JJ grades/NNS through/IN which/WDT the/DT organ/NN has/VBZ passed/VBN ,/, we/PRP should/MD have/VB to/TO look/VB to/TO very/RB ancient/JJ ancestral/JJ forms/NNS ,/, long/JJ since/IN become/VB extinct/JJ ./. We/PRP should/MD be/VB extremely/RB cautious/JJ in/IN concluding/VBG that/IN an/DT organ/NN could/MD not/RB have/VBP been/VBN formed/VBN by/IN transitional/JJ gradations/NNS of/IN some/DT kind/NN ./. Numerous/JJ cases/NNS could/MD be/VB given/VBN amongst/IN the/DT lower/JJR animals/NNS of/IN the/DT same/JJ organ/NN performing/VBG at/IN the/DT same/JJ time/NN wholly/RB distinct/JJ functions/NNS ;/: thus/RB in/IN the/DT larva/NN of/IN the/DT dragon/NN fly/VB and/CC in/IN the/DT fish/NN Cobitis/NNP the/DT alimentary/JJ canal/NN respires/NNS ,/, digests/NNS ,/, and/CC excretes/NNS ./. In/IN the/DT Hydra/NNP ,/, the/DT animal/NN may/MD be/VB turned/VBD inside/IN out/IN ,/, and/CC the/DT exterior/JJ surface/NN will/MD then/RB digest/VB and/CC the/DT stomach/NN respire/NN ./. In/IN such/JJ cases/NNS natural/JJ selection/NN might/MD specialise/NN ,/, if/IN any/DT advantage/NN were/VBD thus/RB gained/VBD ,/, the/DT whole/JJ or/CC part/NN of/IN an/DT organ/NN ,/, which/WDT had/VBD previously/RB performed/VBN two/CD functions/NNS ,/, for/IN one/CD function/NN alone/RB ,/, and/CC thus/RB by/IN insensible/JJ steps/NNS greatly/RB change/NN its/PRP$ nature/NN ./. Many/JJ plants/NNS are/VBP known/VBN which/WDT regularly/RB produce/VB at/IN the/DT same/JJ time/NN differently/RB constructed/VBN flowers/NNS ;/: and/CC if/IN such/JJ plants/NNS were/VBD to/TO produce/VB one/CD kind/NN alone/RB ,/, a/DT great/JJ change/NN would/MD be/VB effected/VBN with/IN comparative/JJ suddenness/NN in/IN the/DT character/NN of/IN the/DT species/NN ./. It/PRP is/VBZ ,/, however/RB ,/, probable/JJ that/IN the/DT two/CD sorts/NNS of/IN flowers/NNS borne/VBN by/IN the/DT same/JJ plant/NN were/VBD originally/RB differentiated/VBN by/IN finely/RB graduated/VBN steps/NNS ,/, which/WDT may/MD still/RB be/VB followed/VBD in/IN some/DT few/JJ cases/NNS ./. Again/RB ,/, two/CD distinct/JJ organs/NNS ,/, or/CC the/DT same/JJ organ/NN under/IN two/CD very/RB different/JJ forms/NNS ,/, may/MD simultaneously/RB perform/VB in/IN the/DT same/JJ individual/JJ the/DT same/JJ function/NN ,/, and/CC this/DT is/VBZ an/DT extremely/RB important/JJ means/VBZ of/IN transition/NN :/: to/TO give/VB one/CD instance/NN ,/, there/EX are/VBP fish/NN with/IN gills/NNS or/CC branchiae/NN that/IN breathe/VB the/DT air/NN dissolved/VBN in/IN the/DT water/NN ,/, at/IN the/DT same/JJ time/NN that/IN they/PRP breathe/VB free/JJ air/NN in/IN their/PRP$ swimbladders/NNS ,/, this/DT latter/NN organ/NN being/VBG divided/VBN by/IN highly/RB vascular/JJ partitions/NNS and/CC having/VBG a/DT ductus/JJ pneumaticus/JJ for/IN the/DT supply/NN of/IN air/NN ./. To/TO give/VB another/DT instance/NN from/IN the/DT vegetable/NN kingdom/NN :/: plants/NNS climb/VB by/IN three/CD distinct/JJ means/VBZ ,/, by/IN spirally/RB twining/VBG ,/, by/IN clasping/VBG a/DT support/NN with/IN their/PRP$ sensitive/JJ tendrils/NNS ,/, and/CC by/IN the/DT emission/NN of/IN aerial/JJ rootlets/NNS ;/: these/DT three/CD means/VBZ are/VBP usually/RB found/VBD in/IN distinct/JJ groups/NNS ,/, but/CC some/DT few/JJ species/NN exhibit/NN two/CD of/IN the/DT means/VBZ ,/, or/CC even/RB all/DT three/CD ,/, combined/VBN in/IN the/DT same/JJ individual/JJ ./. In/IN all/DT such/JJ cases/NNS one/CD of/IN the/DT two/CD organs/NNS might/MD readily/RB be/VB modified/VBN and/CC perfected/VBN so/RB as/IN to/TO perform/VB all/DT the/DT work/NN ,/, being/VBG aided/VBN during/IN the/DT progress/NN of/IN modification/NN by/IN the/DT other/JJ organ/NN ;/: and/CC then/RB this/DT other/JJ organ/NN might/MD be/VB modified/VBN for/IN some/DT other/JJ and/CC quite/RB distinct/JJ purpose/NN ,/, or/CC be/VB wholly/RB obliterated/VBN ./. The/DT illustration/NN of/IN the/DT swimbladder/NN in/IN fishes/NNS is/VBZ a/DT good/JJ one/CD ,/, because/IN it/PRP shows/VBZ us/PRP clearly/RB the/DT highly/RB important/JJ fact/NN that/IN an/DT organ/NN originally/RB constructed/VBN for/IN one/CD purpose/NN ,/, namely/RB ,/, flotation/NN ,/, may/MD be/VB converted/VBN into/IN one/CD for/IN a/DT widely/RB different/JJ purpose/NN ,/, namely/RB ,/, respiration/NN ./. The/DT swimbladder/NN has/VBZ ,/, also/RB ,/, been/VBN worked/VBD in/IN as/IN an/DT accessory/NN to/TO the/DT auditory/JJ organs/NNS of/IN certain/JJ fishes/NNS ./. All/DT physiologists/NNS admit/VB that/IN the/DT swimbladder/NN is/VBZ homologous/RB ,/, or/CC "/" ideally/RB similar/JJ "/" in/IN position/NN and/CC structure/NN with/IN the/DT lungs/NNS of/IN the/DT higher/JJR vertebrate/JJ animals/NNS :/: hence/RB there/EX is/VBZ no/DT reason/NN to/TO doubt/NN that/IN the/DT swimbladder/NN has/VBZ actually/RB been/VBN converted/VBN into/IN lungs/NNS ,/, or/CC an/DT organ/NN used/VBN exclusively/RB for/IN respiration/NN ./. According/VBG to/TO this/DT view/NN it/PRP may/MD be/VB inferred/VBD that/IN all/DT vertebrate/JJ animals/NNS with/IN true/JJ lungs/NNS are/VBP descended/VBD by/IN ordinary/JJ generation/NN from/IN an/DT ancient/JJ and/CC unknown/JJ prototype/NN ,/, which/WDT was/VBD furnished/VBN with/IN a/DT floating/VBG apparatus/NN or/CC swimbladder/NN ./. We/PRP can/MD thus/RB ,/, as/IN I/PRP infer/VB from/IN Owen's/NNP interesting/JJ description/NN of/IN these/DT parts/NNS ,/, understand/VB the/DT strange/JJ fact/NN that/IN every/DT particle/NN of/IN food/NN and/CC drink/NN &/CC which/WDT we/PRP swallow/VB has/VBZ to/TO pass/VB over/IN the/DT orifice/NN of/IN the/DT trachea/NN ,/, with/IN some/DT risk/NN of/IN falling/VBG into/IN the/DT lungs/NNS ,/, notwithstanding/IN the/DT beautiful/JJ contrivance/NN by/IN which/WDT the/DT glottis/NN is/VBZ closed/VBN ./. In/IN the/DT higher/JJR Vertebrate/NNP the/DT branchiae/NN have/VBP wholly/RB disappeared/VBD but/CC in/IN the/DT embryo/NN the/DT slits/NNS on/IN the/DT sides/NNS of/IN the/DT neck/NN and/CC the/DT loop/NN like/IN course/NN of/IN the/DT arteries/NNS still/RB mark/NN their/PRP$ former/JJ position/NN ./. But/CC it/PRP is/VBZ conceivable/JJ that/IN the/DT now/RB utterly/RB lost/VBD branchiae/NN might/MD have/VB been/VBN gradually/RB worked/VBD in/IN by/IN natural/JJ selection/NN for/IN some/DT distinct/JJ purpose/NN :/: for/IN instance/NN ,/, Landois/NNP has/VBZ shown/VBN that/IN the/DT wings/NNS of/IN insects/NNS are/VBP developed/VBN from/IN the/DT tracheae/NN ;/: it/PRP is/VBZ therefore/RB highly/RB probable/JJ that/IN in/IN this/DT great/JJ class/NN organs/NNS which/WDT once/RB served/VBN for/IN respiration/NN have/VBP been/VBN actually/RB converted/VBN into/IN organs/NNS for/IN flight/NN ./. In/IN considering/VBG transitions/NNS of/IN organs/NNS ,/, it/PRP is/VBZ so/RB important/JJ to/TO bear/VB in/IN mind/NN the/DT probability/NN of/IN conversion/NN from/IN one/CD function/NN to/TO another/DT ,/, that/IN I/PRP will/MD give/VB another/DT instance/NN ./. Pedunculated/VBN cirripedes/NNS have/VBP two/CD minute/NN folds/NNS of/IN skin/NN ,/, called/VBN by/IN me/PRP the/DT ovigerous/JJ frena/NN ,/, which/WDT serve/VB ,/, through/IN the/DT means/VBZ of/IN a/DT sticky/JJ secretion/NN ,/, to/TO retain/VB the/DT eggs/NNS until/IN they/PRP are/VBP hatched/VBN within/IN the/DT sack/NN ./. These/DT cirripedes/NNS have/VBP no/DT branchiae/NN ,/, the/DT whole/JJ surface/NN of/IN the/DT body/NN and/CC of/IN the/DT sack/NN ,/, together/RB with/IN the/DT small/JJ frena/NN ,/, serving/VBG for/IN respiration/NN ./. The/DT Balanidae/NNP or/CC sessile/NN cirripedes/NNS ,/, on/IN the/DT other/JJ hand/NN ,/, have/VBP no/DT ovigerous/JJ frena/NN ,/, the/DT eggs/NNS lying/VBG loose/JJ at/IN the/DT bottom/NN of/IN the/DT sack/NN ,/, within/IN the/DT well/RB enclosed/VBN shell/NN ;/: but/CC they/PRP have/VBP ,/, in/IN the/DT same/JJ relative/JJ position/NN with/IN the/DT frena/NN ,/, large/JJ ,/, much/JJ folded/VBN membranes/NNS ,/, which/WDT freely/RB communicate/VB with/IN the/DT circulatory/JJ lacunae/NN of/IN the/DT sack/NN and/CC body/NN ,/, and/CC which/WDT have/VBP been/VBN considered/VBN by/IN all/DT naturalists/NNS to/TO act/NN as/IN branchiae/NN ./. Now/RB I/PRP think/VBP no/DT one/CD will/MD dispute/NN that/IN the/DT ovigerous/JJ frena/NN in/IN the/DT one/CD family/NN are/VBP strictly/RB homologous/RB with/IN the/DT branchiae/NN of/IN the/DT other/JJ family/NN ;/: indeed/RB ,/, they/PRP graduate/NN into/IN each/DT other/JJ ./. Therefore/RB it/PRP need/NN not/RB be/VB doubted/VBD that/IN the/DT two/CD little/JJ folds/NNS of/IN skin/NN ,/, which/WDT originally/RB served/VBN as/IN ovigerous/JJ frena/NN ,/, but/CC which/WDT ,/, likewise/RB ,/, very/RB slightly/RB aided/VBN in/IN the/DT act/NN of/IN respiration/NN ,/, have/VBP been/VBN gradually/RB converted/VBN by/IN natural/JJ selection/NN into/IN branchiae/NN simply/RB through/IN an/DT increase/NN in/IN their/PRP$ size/NN and/CC the/DT obliteration/NN of/IN their/PRP$ adhesive/JJ glands/NNS ./. If/IN all/DT pedunculated/VBN cirripedes/NNS had/VBD become/VB extinct/JJ ,/, and/CC they/PRP have/VBP suffered/VBD far/RB more/JJR extinction/NN than/IN have/VBP sessile/NN cirripedes/NNS ,/, who/WP would/MD ever/RB have/VBP imagined/VBN that/IN the/DT branchiae/NN in/IN this/DT latter/NN family/NN had/VBD originally/RB existed/VBD as/IN organs/NNS for/IN preventing/VBG the/DT ova/NN from/IN being/VBG washed/VBN out/IN of/IN the/DT sack/NN ?/. There/EX is/VBZ another/DT possible/JJ mode/NN of/IN transition/NN ,/, namely/RB ,/, through/IN the/DT acceleration/NN or/CC retardation/NN of/IN the/DT period/NN of/IN reproduction/NN ./. This/DT has/VBZ lately/RB been/VBN insisted/VBD on/IN by/IN Prof/NNP ./. Cope/NNP and/CC others/NNS in/IN the/DT United/NNP States/NNPS ./. It/PRP is/VBZ now/RB known/VBN that/IN some/DT animals/NNS are/VBP capable/JJ of/IN reproduction/NN at/IN a/DT very/RB early/JJ age/NN ,/, before/IN they/PRP have/VBP acquired/VBN their/PRP$ perfect/JJ characters/NNS ;/: and/CC if/IN this/DT power/NN became/VBD thoroughly/RB well/RB developed/VBN in/IN a/DT species/NN ,/, it/PRP seems/VBZ probable/JJ that/IN the/DT adult/NN stage/NN of/IN development/NN would/MD sooner/RBR or/CC later/RB be/VB lost/VBD ;/: and/CC in/IN this/DT case/NN ,/, especially/RB if/IN the/DT larva/NN differed/VBD much/JJ from/IN the/DT mature/JJ form/NN ,/, the/DT character/NN of/IN the/DT species/NN would/MD be/VB greatly/RB changed/VBN and/CC degraded/JJ ./. Again/RB ,/, not/RB a/DT few/JJ animals/NNS ,/, after/IN arriving/VBG at/IN maturity/NN ,/, go/VB on/IN changing/VBG in/IN character/NN during/IN nearly/RB their/PRP$ whole/JJ lives/NNS ./. With/IN mammals/NNS ,/, for/IN instance/NN ,/, the/DT form/NN of/IN the/DT skull/NN is/VBZ often/RB much/JJ altered/VBN with/IN age/NN ,/, of/IN which/WDT Dr/NNP ./. Murie/NNP has/VBZ given/VBN some/DT striking/JJ instances/NNS with/IN seals/NNS ;/: every/DT one/CD knows/VBZ how/WRB the/DT horns/NNS of/IN stags/NNS become/VB more/JJR and/CC more/JJR branched/VBN ,/, and/CC the/DT plumes/NNS of/IN some/DT birds/NNS become/VB more/JJR finely/RB developed/VBN ,/, as/IN they/PRP grow/VB older/JJR ./. Prof/NNP ./. Cope/NNP states/NNS that/IN the/DT teeth/NNS of/IN certain/JJ lizards/NNS change/NN much/JJ in/IN shape/NN with/IN advancing/VBG years/NNS ;/: with/IN crustaceans/NNS not/RB only/RB many/JJ trivial/JJ ,/, but/CC some/DT important/JJ parts/NNS assume/VB a/DT new/JJ character/NN ,/, as/IN recorded/VBN by/IN Fritz/NNP Muller/NNP ,/, after/IN maturity/NN ./. In/IN all/DT such/JJ cases/NNS ,/, and/CC many/JJ could/MD be/VB given/VBN ,/, if/IN the/DT age/NN for/IN reproduction/NN were/VBD retarded/JJ ,/, the/DT character/NN of/IN the/DT species/NN ,/, at/IN least/JJS in/IN its/PRP$ adult/NN state/NN ,/, would/MD be/VB modified/VBN ;/: nor/CC is/VBZ it/PRP improbable/JJ that/IN the/DT previous/JJ and/CC earlier/RBR stages/NNS of/IN development/NN would/MD in/IN some/DT cases/NNS be/VB hurried/VBD through/IN and/CC finally/RB lost/VBD ./. Whether/IN species/NN have/VBP often/RB or/CC ever/RB been/VBN modified/VBN through/IN this/DT comparatively/RB sudden/JJ mode/NN of/IN transition/NN ,/, I/PRP can/MD form/NN no/DT opinion/NN ;/: but/CC if/IN this/DT has/VBZ occurred/VBN ,/, it/PRP is/VBZ probable/JJ that/IN the/DT differences/NNS between/IN the/DT young/JJ and/CC the/DT mature/JJ ,/, and/CC between/IN the/DT mature/JJ and/CC the/DT old/JJ ,/, were/VBD primordially/RB acquired/VBN by/IN graduated/VBN steps/NNS ./. Special/JJ Difficulties/NNP of/IN the/DT Theory/NNP Of/IN Natural/NNP Selection/NN Although/IN we/PRP must/MD be/VB extremely/RB cautious/JJ in/IN concluding/VBG that/IN any/DT organ/NN could/MD not/RB have/VBP been/VBN produced/VBN by/IN successive/JJ ,/, small/JJ ,/, transitional/JJ gradations/NNS ,/, yet/RB undoubtedly/RB serious/JJ cases/NNS of/IN difficulty/NN occur/VB ./. One/CD of/IN the/DT most/RBS serious/JJ is/VBZ that/IN of/IN neuter/NN insects/NNS ,/, which/WDT are/VBP often/RB differently/RB constructed/VBN from/IN either/DT the/DT males/NNS or/CC fertile/JJ females/NNS ;/: but/CC this/DT case/NN will/MD be/VB treated/VBN of/IN in/IN the/DT next/JJ chapter/NN ./. The/DT electric/JJ organs/NNS of/IN fishes/NNS offer/NN another/DT case/NN of/IN special/JJ difficulty/NN ;/: for/IN it/PRP is/VBZ impossible/JJ to/TO conceive/VB by/IN ,/, what/WP steps/NNS these/DT wondrous/JJ organs/NNS have/VBP been/VBN produced/VBN ./. But/CC this/DT is/VBZ not/RB surprising/JJ ,/, for/IN we/PRP do/VBP not/RB even/RB know/VB of/IN what/WP use/NN they/PRP are/VBP ./. In/IN the/DT Gymnotus/NNP and/CC torpedo/VB they/PRP no/DT doubt/NN serve/VB as/IN powerful/JJ means/VBZ of/IN defence/NN ,/, and/CC perhaps/RB for/IN securing/VBG prey/NN ;/: yet/RB in/IN the/DT ray/NN ,/, as/IN observed/VBN by/IN Matteucci/NNP ,/, an/DT analogous/JJ organ/NN in/IN the/DT tail/NN manifests/NNS but/CC little/JJ electricity/NN ,/, even/RB when/WRB the/DT animal/NN is/VBZ greatly/RB irritated/VBN ;/: so/RB little/JJ ,/, that/IN it/PRP can/MD hardly/RB be/VB of/IN any/DT use/NN for/IN the/DT above/IN purposes/NNS ./. Moreover/RB ,/, in/IN the/DT ray/NN ,/, besides/IN the/DT organ/NN just/RB referred/VBN to/TO ,/, there/EX is/VBZ ,/, as/IN Dr/NNP ./. R/NN ./. McDonnell/NNP has/VBZ shown/VBN ,/, another/DT organ/NN near/IN the/DT head/NN ,/, not/RB known/VBN to/TO be/VB electrical/JJ ,/, but/CC which/WDT appears/VBZ to/TO be/VB the/DT real/JJ homologue/NN of/IN the/DT electric/JJ battery/NN in/IN the/DT torpedo/VB ./. It/PRP is/VBZ generally/RB admitted/VBD that/IN there/EX exists/VBZ between/IN these/DT organs/NNS and/CC ordinary/JJ muscle/NN a/DT close/VB analogy/NN ,/, in/IN intimate/JJ structure/NN ,/, in/IN the/DT distribution/NN of/IN the/DT nerves/NNS ,/, and/CC in/IN the/DT manner/NN in/IN which/WDT they/PRP are/VBP acted/VBD on/IN by/IN various/JJ reagents/NNS ./. It/PRP should/MD ,/, also/RB ,/, be/VB especially/RB observed/VBN that/IN muscular/JJ contraction/NN is/VBZ accompanied/VBN by/IN an/DT electrical/JJ discharge/NN ;/: and/CC ,/, as/IN Dr/NNP ./. Radcliffe/NNP insists/VBZ ,/, "/" in/IN the/DT electrical/JJ apparatus/NN of/IN the/DT torpedo/VB during/IN rest/NN ,/, there/EX would/MD seem/VB be/VB a/DT charge/NN in/IN every/DT respect/NN like/IN that/IN which/WDT is/VBZ met/VBN with/IN in/IN muscle/NN and/CC nerve/NN during/IN rest/NN ,/, and/CC the/DT discharge/NN of/IN the/DT torpedo/VB ,/, instead/RB of/IN being/VBG peculiar/JJ ,/, may/MD be/VB only/RB another/DT form/NN of/IN the/DT discharge/NN which/WDT depends/VBZ upon/IN the/DT action/NN of/IN muscle/NN and/CC motor/NN nerve/NN ./. "/" Beyond/IN this/DT we/PRP cannot/MD at/IN present/JJ go/VB in/IN the/DT way/NN of/IN explanation/NN ;/: but/CC as/IN we/PRP know/VB so/RB little/JJ about/IN the/DT uses/VBZ of/IN these/DT organs/NNS ,/, and/CC as/IN we/PRP know/VB nothing/NN about/IN the/DT habits/NNS and/CC structure/NN of/IN the/DT progenitors/NNS of/IN the/DT existing/VBG electric/JJ fishes/NNS ,/, it/PRP would/MD be/VB extremely/RB bold/JJ to/TO maintain/VB that/IN no/DT serviceable/JJ transitions/NNS are/VBP possible/JJ by/IN which/WDT these/DT organs/NNS might/MD have/VB been/VBN gradually/RB developed/VBN ./. These/DT organs/NNS appear/VB at/IN first/JJ to/TO offer/NN another/DT and/CC far/RB more/JJR serious/JJ difficulty/NN ;/: for/IN they/PRP occur/VB in/IN about/IN a/DT dozen/NN kinds/NNS of/IN fish/NN ,/, of/IN which/WDT several/JJ are/VBP widely/RB remote/JJ in/IN their/PRP$ affinities/NNS ./. When/WRB the/DT same/JJ organ/NN is/VBZ found/VBN in/IN several/JJ members/NNS of/IN the/DT same/JJ class/NN ,/, especially/RB if/IN in/IN members/NNS having/VBG very/RB different/JJ habits/NNS of/IN life/NN ,/, we/PRP may/MD generally/RB attribute/VBP its/PRP$ presence/NN to/TO inheritance/NN from/IN a/DT common/JJ ancestor/NN ;/: and/CC its/PRP$ absence/NN in/IN some/DT of/IN the/DT members/NNS to/TO loss/NN through/IN disuse/NN or/CC natural/JJ selection/NN ./. So/RB that/IN ,/, if/IN the/DT electric/JJ organs/NNS had/VBD been/VBN inherited/VBN from/IN some/DT one/CD ancient/JJ progenitor/NN ,/, we/PRP might/MD have/VB expected/VBN that/IN all/DT electric/JJ fishes/NNS would/MD have/VB been/VBN specially/RB related/VBN to/TO each/DT other/JJ ;/: but/CC this/DT is/VBZ far/RB from/IN the/DT case/NN ./. Nor/CC does/VBZ geology/NN at/IN all/DT lead/VB to/TO the/DT belief/NN that/IN most/RBS fishes/NNS formerly/RB possessed/VBD electric/JJ organs/NNS ,/, which/WDT their/PRP$ modified/VBN descendants/NNS have/VBP now/RB lost/VBD ./. But/CC when/WRB we/PRP look/VB at/IN the/DT subject/NN more/JJR closely/RB ,/, we/PRP find/VB in/IN the/DT several/JJ fishes/NNS provided/VBN with/IN electric/JJ organs/NNS ,/, that/IN these/DT are/VBP situated/VBN in/IN different/JJ parts/NNS of/IN the/DT body/NN ,/, that/IN they/PRP differ/VBP in/IN construction/NN ,/, as/IN in/IN the/DT arrangement/NN of/IN the/DT plates/NNS ,/, and/CC ,/, according/VBG to/TO Pacini/NNP ,/, in/IN the/DT process/NN or/CC means/VBZ by/IN which/WDT the/DT electricity/NN is/VBZ excited/VBN and/CC lastly/RB ,/, in/IN being/VBG supplied/VBN with/IN nerves/NNS proceeding/NN from/IN different/JJ sources/NNS ,/, and/CC this/DT is/VBZ perhaps/RB the/DT most/RBS important/JJ of/IN all/DT the/DT differences/NNS ./. Hence/RB in/IN the/DT several/JJ fishes/NNS furnished/VBN with/IN electric/JJ organs/NNS ,/, these/DT cannot/MD be/VB considered/VBN as/IN homologous/RB ,/, but/CC only/RB as/IN analogous/JJ in/IN function/NN ./. Consequently/RB there/EX is/VBZ no/DT reason/NN to/TO suppose/VB that/IN they/PRP have/VBP been/VBN inherited/VBN from/IN a/DT common/JJ progenitor/NN ;/: for/IN had/VBD this/DT been/VBN the/DT case/NN they/PRP would/MD have/VB closely/RB resembled/VBD each/DT other/JJ in/IN all/DT respects/NNS ./. Thus/RB the/DT difficulty/NN of/IN an/DT organ/NN ,/, apparently/RB the/DT same/JJ ,/, arising/VBG in/IN several/JJ remotely/RB allied/VBN species/NN ,/, disappears/VBZ ,/, leaving/VBG only/RB the/DT lesser/JJR yet/RB still/RB great/JJ difficulty/NN ;/: namely/RB ,/, by/IN what/WP graduated/VBN steps/NNS these/DT organs/NNS have/VBP been/VBN developed/VBN in/IN each/DT separate/JJ group/NN of/IN fishes/NNS ./. The/DT luminous/JJ organs/NNS which/WDT occur/VB in/IN a/DT few/JJ insects/NNS ,/, belonging/VBG to/TO widely/RB different/JJ families/NNS ,/, and/CC which/WDT are/VBP situated/VBN in/IN different/JJ parts/NNS of/IN the/DT body/NN ,/, offer/NN ,/, under/IN our/PRP$ present/JJ state/NN of/IN ignorance/NN ,/, a/DT difficulty/NN almost/RB exactly/RB parallel/JJ with/IN that/IN of/IN the/DT electric/JJ organs/NNS ./. Other/JJ similar/JJ cases/NNS could/MD be/VB given/VBN ;/: for/IN instance/NN in/IN plants/NNS ,/, the/DT very/RB curious/JJ contrivance/NN of/IN a/DT mass/NN of/IN pollen/NN grains/NNS ,/, borne/VBN on/IN a/DT foot/NN stalk/VBP with/IN an/DT adhesive/JJ gland/NN ,/, is/VBZ apparently/RB the/DT same/JJ in/IN Orchis/NNP and/CC Asclepias/NNP ,/, genera/NN almost/RB as/IN remote/JJ as/IN is/VBZ possible/JJ amongst/IN flowering/NN plants/NNS ;/: but/CC here/RB again/RB the/DT parts/NNS are/VBP not/RB homologous/RB ./. In/IN all/DT cases/NNS of/IN beings/NNS ,/, far/RB removed/VBN from/IN each/DT other/JJ in/IN the/DT scale/NN of/IN organisation/NN ,/, which/WDT are/VBP furnished/VBN with/IN similar/JJ and/CC peculiar/JJ organs/NNS ,/, it/PRP will/MD be/VB found/VBD that/IN although/IN the/DT general/JJ appearance/NN and/CC function/NN of/IN the/DT organs/NNS may/MD be/VB the/DT same/JJ ,/, yet/RB fundamental/JJ differences/NNS between/IN them/PRP can/MD always/RB be/VB detected/VBN ./. For/IN instance/NN ,/, the/DT eyes/NNS of/IN cephalopods/NNS or/CC cuttle/NN fish/NN and/CC of/IN vertebrate/JJ animals/NNS appear/VB wonderfully/RB alike/RB ;/: and/CC in/IN such/JJ widely/RB sundered/VBN groups/NNS no/DT part/NN of/IN this/DT resemblance/NN can/MD be/VB due/JJ to/TO inheritance/NN from/IN a/DT common/JJ progenitor/NN ./. Mr/NNP ./. Mivart/NNP has/VBZ advanced/VBN this/DT case/NN as/IN one/CD of/IN special/JJ difficulty/NN ,/, but/CC I/PRP am/VBP unable/JJ to/TO see/VB the/DT force/NN of/IN his/PRP$ argument/NN ./. An/DT organ/NN for/IN vision/NN must/MD be/VB formed/VBN of/IN transparent/JJ tissue/NN ,/, and/CC must/MD include/VB some/DT sort/NN of/IN lens/NN for/IN throwing/VBG an/DT image/NN at/IN the/DT back/RB of/IN a/DT darkened/VBD chamber/NN ./. Beyond/IN this/DT superficial/JJ resemblance/NN ,/, there/EX is/VBZ hardly/RB any/DT real/JJ similarity/NN between/IN the/DT eyes/NNS of/IN cuttle/NN fish/NN and/CC vertebrates/NNS ,/, as/IN may/MD be/VB seen/VBN by/IN consulting/NN Hensen's/NNP admirable/JJ memoir/NN on/IN these/DT organs/NNS in/IN the/DT Cephalopoda/NNP ./. It/PRP is/VBZ impossible/JJ for/IN me/PRP here/RB to/TO enter/VB on/IN details/NNS ,/, but/CC I/PRP may/MD specify/VB a/DT few/JJ of/IN the/DT points/NNS of/IN difference/NN ./. The/DT crystalline/JJ lens/NN in/IN the/DT higher/JJR cuttle/NN fish/NN consists/VBZ of/IN two/CD parts/NNS ,/, placed/VBN one/CD behind/IN the/DT other/JJ like/IN two/CD lenses/NNS ,/, both/DT having/VBG a/DT very/RB different/JJ structure/NN and/CC disposition/NN to/TO what/WP occurs/VBZ in/IN the/DT vertebrata/NN ./. The/DT retina/NN is/VBZ wholly/RB different/JJ ,/, with/IN an/DT actual/JJ inversion/NN of/IN the/DT elemental/JJ parts/NNS ,/, and/CC with/IN a/DT large/JJ nervous/JJ ganglion/NN included/VBD within/IN the/DT membranes/NNS of/IN the/DT eye/NN ./. The/DT relations/NNS of/IN the/DT muscles/NNS are/VBP as/IN different/JJ as/IN it/PRP is/VBZ possible/JJ to/TO conceive/VB ,/, and/CC so/RB in/IN other/JJ points/NNS ./. Hence/RB it/PRP is/VBZ not/RB a/DT little/JJ difficult/JJ to/TO decide/VB how/WRB far/RB even/RB the/DT same/JJ terms/NNS ought/MD to/TO be/VB employed/VBN in/IN describing/VBG the/DT eyes/NNS of/IN the/DT Cephalopoda/NNP and/CC Vertebrata/NNP ./. It/PRP is/VBZ ,/, of/IN course/NN ,/, open/JJ to/TO any/DT one/CD to/TO deny/VB that/IN the/DT eye/NN in/IN either/DT case/NN could/MD have/VB been/VBN developed/VBN through/IN the/DT natural/JJ selection/NN of/IN successive/JJ slight/JJ variations/NNS ;/: but/CC if/IN this/DT be/VB admitted/VBD in/IN the/DT one/CD case/NN ,/, it/PRP is/VBZ clearly/RB possible/JJ in/IN the/DT other/JJ ;/: and/CC fundamental/JJ differences/NNS of/IN structure/NN in/IN the/DT visual/JJ organs/NNS of/IN two/CD groups/NNS might/MD have/VB been/VBN anticipated/VBN ,/, in/IN accordance/NN with/IN this/DT view/NN of/IN their/PRP$ manner/NN of/IN formation/NN ./. As/IN two/CD men/NNS have/VBP sometimes/RB independently/RB hit/VBD on/IN the/DT same/JJ invention/NN ,/, so/RB in/IN the/DT several/JJ foregoing/NN cases/NNS it/PRP appears/VBZ that/IN natural/JJ selection/NN ,/, working/VBG for/IN the/DT good/JJ of/IN each/DT being/VBG ,/, and/CC taking/VBG advantage/NN of/IN all/DT favourable/JJ variations/NNS ,/, has/VBZ produced/VBN similar/JJ organs/NNS ,/, as/IN far/RB as/IN function/NN is/VBZ concerned/VBN ,/, in/IN distinct/JJ organic/JJ beings/NNS ,/, which/WDT owe/VBP none/NN of/IN their/PRP$ structure/NN in/IN common/JJ to/TO inheritance/NN from/IN a/DT common/JJ progenitor/NN ./. Fritz/NNP Muller/NNP ,/, in/IN order/NN to/TO test/NN the/DT conclusions/NNS arrived/VBD at/IN in/IN this/DT volume/NN ,/, has/VBZ followed/VBN out/IN with/IN much/JJ care/NN a/DT nearly/RB similar/JJ line/NN of/IN argument/NN ./. Several/JJ families/NNS of/IN crustaceans/NNS include/VBP a/DT few/JJ species/NN ,/, possessing/VBG an/DT air/NN breathing/NN apparatus/NN and/CC fitted/VBN to/TO live/VB out/IN of/IN the/DT water/NN ./. In/IN two/CD of/IN these/DT families/NNS ,/, which/WDT were/VBD more/JJR especially/RB examined/VBD by/IN Muller/NNP and/CC which/WDT are/VBP nearly/RB related/VBN to/TO each/DT other/JJ ,/, the/DT species/NN agree/VB most/RBS closely/RB in/IN all/DT important/JJ characters/NNS ;/: namely/RB ,/, in/IN their/PRP$ sense/NN organs/NNS ,/, circulating/VBG system/NN ,/, in/IN the/DT position/NN of/IN the/DT tufts/NNS of/IN hair/NN within/IN their/PRP$ complex/JJ stomachs/NNS ,/, and/CC lastly/RB in/IN the/DT whole/JJ structure/NN of/IN the/DT water/NN breathing/NN branchiae/NN ,/, even/RB to/TO the/DT microscopical/JJ hooks/NNS by/IN which/WDT they/PRP are/VBP cleansed/VBD ./. Hence/RB it/PRP might/MD have/VB been/VBN expected/VBN that/IN in/IN the/DT few/JJ species/NN belonging/VBG to/TO both/DT families/NNS which/WDT live/VB on/IN the/DT land/NN ,/, the/DT equally/RB important/JJ air/NN breathing/NN apparatus/NN would/MD have/VB been/VBN the/DT same/JJ ;/: for/IN why/WRB should/MD this/DT one/CD apparatus/NN ,/, given/VBN for/IN the/DT same/JJ purpose/NN ,/, have/VBP been/VBN made/VBN to/TO differ/VB ,/, whilst/NN all/DT the/DT other/JJ important/JJ organs/NNS were/VBD closely/RB similar/JJ or/CC rather/RB identical/JJ ?/. Fritz/NNP Muller/NNP argues/VBZ that/IN this/DT close/VB similarity/NN in/IN so/RB many/JJ points/NNS of/IN structure/NN must/MD ,/, in/IN accordance/NN with/IN the/DT views/NNS advanced/VBD by/IN me/PRP ,/, be/VB accounted/VBD for/IN by/IN inheritance/NN from/IN a/DT common/JJ progenitor/NN ./. But/CC as/IN the/DT vast/JJ majority/NN of/IN the/DT species/NN in/IN the/DT above/IN two/CD families/NNS ,/, as/IN well/RB as/IN most/RBS other/JJ crustaceans/NNS ,/, are/VBP aquatic/JJ in/IN their/PRP$ habits/NNS ,/, it/PRP is/VBZ improbable/JJ in/IN the/DT highest/JJS degree/NN ,/, that/IN their/PRP$ common/JJ progenitor/NN should/MD have/VB been/VBN adapted/VBN for/IN breathing/NN air/NN was/VBD thus/RB led/VBN carefully/RB to/TO examine/VB the/DT apparatus/NN in/IN the/DT air/NN breathing/NN species/NN ;/: and/CC he/PRP found/VBD it/PRP to/TO differ/VB in/IN each/DT in/IN several/JJ important/JJ points/NNS ,/, as/IN in/IN the/DT position/NN of/IN the/DT orifices/NNS ,/, in/IN the/DT manner/NN in/IN which/WDT they/PRP are/VBP opened/VBD and/CC closed/VBD ,/, and/CC in/IN some/DT accessory/NN details/NNS ./. 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Consequently/RB natural/JJ selection/NN would/MD have/VB had/VBD different/JJ materials/NNS or/CC variations/NNS to/TO work/NN on/IN ,/, in/IN order/NN to/TO arrive/VB at/IN the/DT same/JJ functional/JJ result/NN ;/: and/CC the/DT structures/NNS thus/RB acquired/VBN would/MD almost/RB necessarily/RB have/VBP differed/VBD ./. On/IN the/DT hypothesis/NN of/IN separate/JJ acts/NNS of/IN creation/NN the/DT whole/JJ case/NN remains/VBZ unintelligible/JJ ./. This/DT line/NN of/IN argument/NN seems/VBZ to/TO have/VB had/VBD great/JJ weight/NN in/IN leading/VBG Fritz/NNP Muller/NNP to/TO accept/VB the/DT views/NNS maintained/VBN by/IN me/PRP in/IN this/DT volume/NN ./. Another/DT distinguished/VBN zoologist/NN ,/, the/DT late/JJ Professor/NNP Claparide/NNP ,/, has/VBZ argued/VBN in/IN the/DT same/JJ manner/NN ,/, and/CC has/VBZ arrived/VBN at/IN the/DT same/JJ result/NN ./. 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I/PRP will/MD give/VB one/CD other/JJ instance/NN ;/: for/IN this/DT subject/NN of/IN the/DT same/JJ end/NN being/VBG gained/VBD by/IN the/DT most/RBS diversified/JJ means/VBZ well/RB deserves/VBZ attention/NN ./. Some/DT authors/NNS maintain/VB that/IN organic/JJ beings/NNS have/VBP been/VBN formed/VBN in/IN many/JJ ways/NNS for/IN the/DT sake/NN of/IN mere/JJ variety/NN ,/, almost/RB like/IN toys/NNS in/IN a/DT shop/NN ,/, but/CC such/JJ a/DT view/NN of/IN nature/NN is/VBZ incredible/JJ ./. With/IN plants/NNS having/VBG separated/VBN sexes/NNS ,/, and/CC with/IN those/DT in/IN which/WDT ,/, though/IN hermaphrodites/NNS ,/, the/DT pollen/NN does/VBZ not/RB spontaneously/RB fall/NN on/IN the/DT stigma/NN ,/, some/DT aid/NN is/VBZ necessary/JJ for/IN their/PRP$ fertilisation/NN ./. 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Cruger/NNP saw/VBD crowds/NNS of/IN large/JJ humble/JJ bees/NNS visiting/VBG the/DT gigantic/JJ flowers/NNS of/IN this/DT orchid/JJ ,/, not/RB in/IN order/NN to/TO suck/VB nectar/NN ,/, but/CC to/TO gnaw/VB off/IN the/DT ridges/NNS within/IN the/DT chamber/NN above/IN the/DT bucket/NN ;/: in/IN doing/VBG this/DT they/PRP frequently/RB pushed/VBD each/DT other/JJ into/IN the/DT bucket/NN ,/, and/CC their/PRP$ wings/NNS being/VBG thus/RB wetted/VBN they/PRP could/MD not/RB fly/VB away/RB ,/, but/CC were/VBD compelled/VBN to/TO crawl/VB out/IN through/IN the/DT passage/NN formed/VBN by/IN the/DT spout/NN or/CC overflow/NN ./. Dr/NNP ./. Cruger/NNP saw/VBD a/DT "/" continual/JJ procession/NN "/" of/IN bees/NNS thus/RB crawling/VBG out/IN of/IN their/PRP$ involuntary/JJ bath/NN ./. The/DT passage/NN is/VBZ narrow/JJ ,/, and/CC is/VBZ roofed/VBN over/IN by/IN the/DT column/NN ,/, so/RB that/IN a/DT bee/NN ,/, in/IN forcing/VBG its/PRP$ way/NN out/IN ,/, first/JJ rubs/NNS its/PRP$ back/RB against/IN the/DT viscid/JJ stigma/NN and/CC then/RB against/IN the/DT viscid/JJ glands/NNS of/IN the/DT pollen/NN masses/NNS ./. The/DT pollen/NN masses/NNS are/VBP thus/RB glued/VBN to/TO the/DT back/RB of/IN the/DT be/VB which/WDT first/JJ happens/VBZ to/TO crawl/VB out/IN through/IN the/DT passage/NN of/IN a/DT lately/RB expanded/VBN flower/NN ,/, and/CC are/VBP thus/RB carried/VBD away/RB ./. Dr/NNP ./. Cruger/NNP sent/VBD me/PRP a/DT flower/NN in/IN spirits/NNS of/IN wine/NN ,/, with/IN a/DT bee/NN which/WDT he/PRP had/VBD killed/VBN before/IN it/PRP had/VBD quite/RB crawled/VBD out/IN with/IN a/DT pollen/NN mass/NN still/RB fastened/VBN to/TO its/PRP$ back/RB ./. 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The/DT construction/NN of/IN the/DT flower/NN in/IN another/DT closely/RB allied/VBN orchid/JJ ,/, namely/RB the/DT Catasetum/NNP ,/, is/VBZ widely/RB different/JJ ,/, though/IN serving/VBG the/DT same/JJ end/NN ;/: and/CC is/VBZ equally/RB curious/JJ ./. Bees/NNP visit/NN these/DT flowers/NNS ,/, like/IN those/DT of/IN the/DT Coryanthes/NNP ,/, in/IN order/NN to/TO gnaw/VB the/DT labellum/NN ;/: in/IN doing/VBG this/DT they/PRP inevitably/RB touch/NN a/DT long/JJ ,/, tapering/VBG ,/, sensitive/JJ projection/NN ,/, or/CC ,/, as/IN I/PRP have/VBP called/VBN it/PRP ,/, the/DT antenna/NN ./. 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We/PRP should/MD also/RB bear/VB in/IN mind/NN that/IN every/DT highly/RB developed/VBN organism/NN has/VBZ passed/VBN through/IN many/JJ changes/NNS ;/: and/CC that/IN each/DT modified/VBN structure/NN tends/VBZ to/TO be/VB inherited/VBN ,/, so/RB that/IN each/DT modification/NN will/MD not/RB readily/RB be/VB quite/RB lost/VBD ,/, but/CC may/MD be/VB again/RB and/CC again/RB further/JJR altered/VBN ./. Hence/RB the/DT structure/NN of/IN each/DT part/NN of/IN each/DT species/NN ,/, for/IN whatever/WDT purpose/NN it/PRP may/MD serve/VB ,/, is/VBZ the/DT sum/NN of/IN many/JJ inherited/VBN changes/NNS ,/, through/IN which/WDT the/DT species/NN has/VBZ passed/VBN during/IN its/PRP$ successive/JJ adaptations/NNS to/TO changed/VBN habits/NNS and/CC conditions/NNS of/IN life/NN ./. Finally/RB then/RB ,/, although/IN in/IN many/JJ cases/NNS it/PRP is/VBZ most/RBS difficult/JJ even/RB to/TO conjecture/NN by/IN what/WP transitions/NNS organs/NNS have/VBP arrived/VBD at/IN their/PRP$ present/JJ state/NN ;/: yet/RB ,/, considering/VBG how/WRB small/JJ the/DT proportion/NN of/IN living/VBG and/CC known/VBN forms/NNS is/VBZ to/TO the/DT extinct/JJ and/CC unknown/JJ ,/, I/PRP have/VBP been/VBN astonished/VBN how/WRB rarely/RB an/DT organ/NN can/MD be/VB named/VBN ,/, towards/IN which/WDT no/DT transitional/JJ grade/NN is/VBZ known/VBN to/TO lead/VB ./. It/PRP certainly/RB is/VBZ true/JJ ,/, that/IN new/JJ organs/NNS appearing/VBG as/IN if/IN created/VBN for/IN some/DT special/JJ purpose/NN ,/, rarely/RB or/CC never/RB appear/VB in/IN any/DT being/VBG ;/: as/IN indeed/RB is/VBZ shown/VBN by/IN that/IN old/JJ ,/, but/CC somewhat/RB exaggerated/VBN ,/, canon/NN in/IN natural/JJ history/NN of/IN "/" Natura/NNP non/FW facit/FW saltum/FW ./. "/" We/PRP meet/VB with/IN this/DT admission/NN in/IN the/DT writings/NNS of/IN almost/RB every/DT experienced/VBN naturalist/NN ;/: or/CC as/IN Milne/NNP Edwards/NNP has/VBZ well/RB expressed/VBN it/PRP ,/, Nature/NNP is/VBZ prodigal/JJ in/IN variety/NN ,/, but/CC niggard/JJ in/IN innovation/NN ./. Why/WRB ,/, on/IN the/DT theory/NN of/IN Creation/NN ,/, should/MD there/EX be/VB so/RB much/JJ variety/NN and/CC so/RB little/JJ real/JJ novelty/NN ?/. Why/WRB should/MD all/DT the/DT parts/NNS and/CC organs/NNS of/IN many/JJ independent/JJ beings/NNS ,/, each/DT supposed/VBN to/TO have/VB been/VBN separately/RB created/VBN for/IN its/PRP$ proper/JJ place/NN in/IN nature/NN ,/, be/VB so/RB commonly/RB linked/VBN together/RB by/IN graduated/VBN steps/NNS ?/. Why/WRB should/MD not/RB Nature/NNP take/VB a/DT sudden/JJ leap/NN from/IN structure/NN to/TO structure/NN ?/. On/IN the/DT theory/NN of/IN natural/JJ selection/NN ,/, we/PRP can/MD clearly/RB understand/VB why/WRB she/PRP should/MD not/RB ;/: for/IN natural/JJ selection/NN acts/NNS only/RB by/IN taking/VBG advantage/NN of/IN slight/JJ successive/JJ variations/NNS ;/: she/PRP can/MD never/RB take/VB a/DT great/JJ and/CC sudden/JJ leap/NN ,/, but/CC must/MD advance/NN by/IN short/JJ and/CC sure/JJ ,/, though/IN slow/JJ steps/NNS ./. Organs/NNPS of/IN little/JJ apparent/JJ Importance/NN ,/, as/IN affected/VBN by/IN Natural/NNP Selection/NN As/IN natural/JJ selection/NN acts/NNS by/IN life/NN and/CC death/NN ,/, by/IN the/DT survival/NN of/IN the/DT fittest/JJS ,/, and/CC by/IN the/DT destruction/NN of/IN the/DT less/JJR well/RB fitted/VBN individuals/NNS ,/, I/PRP have/VBP sometimes/RB felt/VBD great/JJ difficulty/NN in/IN understanding/NN the/DT origin/NN or/CC formation/NN of/IN parts/NNS of/IN little/JJ importance/NN ;/: almost/RB as/IN great/JJ ,/, though/IN of/IN a/DT very/RB different/JJ kind/NN ,/, as/IN in/IN the/DT case/NN of/IN the/DT most/RBS perfect/JJ and/CC complex/JJ organs/NNS ./. In/IN the/DT first/JJ place/NN ,/, we/PRP are/VBP much/JJ too/RB ignorant/JJ in/IN regard/NN to/TO the/DT whole/JJ economy/NN of/IN any/DT one/CD organic/JJ being/VBG ,/, to/TO say/VB what/WP slight/JJ modifications/NNS would/MD be/VB of/IN importance/NN or/CC not/RB ./. 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In/IN these/DT several/JJ cases/NNS ,/, with/IN the/DT exception/NN of/IN that/IN of/IN the/DT well/RB developed/VBN rayflorets/NNS ,/, which/WDT are/VBP of/IN service/NN in/IN making/VBG the/DT flowers/NNS conspicuous/JJ to/TO insects/NNS ,/, natural/JJ selection/NN cannot/MD ,/, as/IN far/RB as/IN we/PRP can/MD judge/NN ,/, have/VBP come/VB into/IN play/VB ,/, or/CC only/RB in/IN a/DT quite/RB subordinate/JJ manner/NN ./. All/DT these/DT modifications/NNS follow/VB from/IN the/DT relative/JJ position/NN and/CC inter/FW action/NN of/IN the/DT parts/NNS ;/: and/CC it/PRP can/MD hardly/RB be/VB doubted/VBD that/IN if/IN all/DT the/DT flowers/NNS and/CC leaves/VBZ on/IN the/DT same/JJ plant/NN had/VBD been/VBN subjected/VBN to/TO the/DT same/JJ external/JJ and/CC internal/JJ condition/NN ,/, as/IN are/VBP the/DT flowers/NNS and/CC leaves/VBZ in/IN certain/JJ positions/NNS ,/, all/DT would/MD have/VB been/VBN modified/VBN in/IN the/DT same/JJ manner/NN ./. 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It/PRP is/VBZ so/RB common/JJ to/TO observe/VB on/IN the/DT same/JJ plant/NN ,/, flowers/NNS indifferently/RB tetramerous/JJ ,/, pentamerous/JJ ,/, &c/NN ./. ,/, that/IN I/PRP need/NN not/RB give/VB examples/NNS ;/: but/CC as/IN numerical/JJ variations/NNS are/VBP comparatively/RB rare/JJ when/WRB the/DT parts/NNS are/VBP few/JJ ,/, I/PRP may/MD mention/VB that/IN ,/, according/VBG to/TO De/NNP Candolle/NNP ,/, the/DT flowers/NNS of/IN Papaver/NNP bracteatum/NN offer/NN either/DT two/CD sepals/NNS with/IN four/CD petals/NNS (/( which/WDT is/VBZ the/DT common/JJ type/NN with/IN poppies/NNS )/SYM ,/, or/CC three/CD sepals/NNS with/IN six/CD petals/NNS ./. 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Thus/RB ,/, as/IN I/PRP am/VBP inclined/VBN to/TO believe/VB ,/, differences/NNS ,/, which/WDT we/PRP consider/VB as/IN important/JJ such/JJ as/IN the/DT arrangement/NN of/IN the/DT leaves/VBZ ,/, the/DT divisions/NNS of/IN the/DT flower/NN or/CC of/IN the/DT ovarium/NN ,/, the/DT position/NN of/IN the/DT ovules/NNS ,/, &c/NN ./. first/JJ appeared/VBD in/IN many/JJ cases/NNS as/IN fluctuating/VBG variations/NNS ,/, which/WDT sooner/RBR or/CC later/RB became/VBD constant/JJ through/IN the/DT nature/NN of/IN the/DT organism/NN and/CC of/IN the/DT surrounding/VBG conditions/NNS ,/, as/IN well/RB as/IN through/IN the/DT intercrossing/VBG of/IN distinct/JJ individuals/NNS ,/, but/CC not/RB through/IN natural/JJ selection/NN ;/: for/IN as/IN these/DT morphological/JJ characters/NNS do/VBP not/RB affect/VB the/DT welfare/NN of/IN the/DT species/NN ,/, any/DT slight/JJ deviations/NNS in/IN them/PRP could/MD not/RB have/VBP been/VBN governed/VBN or/CC accumulated/VBN through/IN this/DT latter/NN agency/NN ./. 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For/IN the/DT best/JJS definition/NN which/WDT has/VBZ ever/RB been/VBN given/VBN of/IN a/DT high/JJ standard/JJ of/IN organisation/NN ,/, is/VBZ the/DT degree/NN to/TO which/WDT the/DT parts/NNS have/VBP been/VBN specialised/VBN or/CC differentiated/VBN ;/: and/CC natural/JJ selection/NN tends/VBZ towards/IN this/DT end/NN ,/, inasmuch/RB as/IN the/DT parts/NNS are/VBP thus/RB enabled/VBD to/TO perform/VB their/PRP$ functions/NNS more/JJR efficiently/RB ./. A/DT distinguished/VBN zoologist/NN ,/, Mr/NNP ./. St/NNP ./. George/NNP Mivart/NNP ,/, has/VBZ recently/RB collected/VBN all/DT the/DT objections/NNS which/WDT have/VBP ever/RB been/VBN advanced/VBD by/IN myself/PRP and/CC others/NNS against/IN the/DT theory/NN of/IN natural/JJ selection/NN ,/, as/IN propounded/VBD by/IN Mr/NNP ./. Wallace/NNP and/CC myself/PRP ,/, and/CC has/VBZ illustrated/VBN them/PRP with/IN admirable/JJ art/NN and/CC force/NN ./. When/WRB thus/RB marshalled/VBD ,/, they/PRP make/VB a/DT formidable/JJ array/NN ;/: and/CC as/IN it/PRP forms/NNS no/DT part/NN of/IN Mr/NNP ./. Mivart's/NNP plan/NN to/TO give/VB the/DT various/JJ facts/NNS and/CC considerations/NNS opposed/VBN to/TO his/PRP$ conclusions/NNS ,/, no/DT slight/JJ effort/NN of/IN reason/NN and/CC memory/NN is/VBZ left/VBN to/TO the/DT reader/NN ,/, who/WP may/MD wish/VB to/TO weigh/VB the/DT evidence/NN on/IN both/DT sides/NNS ./. When/WRB discussing/VBG special/JJ cases/NNS ,/, Mr/NNP ./. Mivart/NNP passes/VBZ over/IN the/DT effects/NNS of/IN the/DT increased/VBN use/NN and/CC disuse/NN of/IN parts/NNS ,/, which/WDT I/PRP have/VBP always/RB maintained/VBN to/TO be/VB highly/RB important/JJ ,/, and/CC have/VBP treated/VBN in/IN my/PRP$ Variation/NNP under/IN Domestication/NNP at/IN greater/JJR length/NN than/IN ,/, as/IN I/PRP believe/VBP ,/, any/DT other/JJ writer/NN ./. He/PRP likewise/RB often/RB assumes/VBZ that/IN I/PRP attribute/VBP nothing/NN to/TO variation/NN ,/, independently/RB of/IN natural/JJ selection/NN ,/, whereas/IN in/IN the/DT work/NN just/RB referred/VBN to/TO I/PRP have/VBP collected/VBN a/DT greater/JJR number/NN of/IN well/RB established/VBN cases/NNS than/IN can/MD be/VB found/VBD in/IN any/DT other/JJ work/NN known/VBN to/TO me/PRP ./. My/PRP$ judgment/NN may/MD not/RB be/VB trustworthy/JJ ,/, but/CC after/IN reading/NN with/IN care/NN Mr/NNP ./. Mivart's/NNP book/NN ,/, and/CC comparing/VBG each/DT section/NN with/IN what/WP I/PRP have/VBP said/VBD on/IN the/DT same/JJ head/NN ,/, I/PRP never/RB before/IN felt/VBD so/RB strongly/RB convinced/VBN of/IN the/DT general/JJ truth/NN of/IN the/DT conclusions/NNS here/RB arrived/VBD at/IN ,/, subject/NN ,/, of/IN course/NN ,/, in/IN so/RB intricate/JJ a/DT subject/NN ,/, to/TO much/JJ partial/JJ error/NN ./. All/DT Mr/NNP ./. Mivart's/NNP objections/NNS will/MD be/VB ,/, or/CC have/VBP been/VBN ,/, considered/VBN in/IN the/DT present/JJ volume/NN ./. The/DT one/CD new/JJ point/NN which/WDT appears/VBZ to/TO have/VB struck/VBD many/JJ readers/NNS is/VBZ ,/, "/" that/IN natural/JJ selection/NN is/VBZ incompetent/JJ to/TO account/NN for/IN the/DT incipient/JJ stages/NNS of/IN useful/JJ structures/NNS ./. "/" This/DT subject/NN is/VBZ intimately/RB connected/VBN with/IN that/IN of/IN the/DT gradation/NN of/IN characters/NNS ,/, often/RB accompanied/VBN by/IN a/DT change/NN of/IN function/NN ,/, for/IN instance/NN ,/, the/DT conversion/NN of/IN a/DT swimbladder/NN into/IN lungs/NNS ,/, points/NNS which/WDT were/VBD discussed/VBN in/IN the/DT last/JJ chapter/NN under/IN two/CD headings/NNS ./. Nevertheless/RB ,/, I/PRP will/MD here/RB consider/VB in/IN some/DT detail/NN several/JJ of/IN the/DT cases/NNS advanced/VBD by/IN Mr/NNP ./. Mivart/NNP ,/, selecting/VBG those/DT which/WDT are/VBP the/DT most/RBS illustrative/JJ ,/, as/IN want/VBP of/IN space/NN prevents/VBZ me/PRP from/IN considering/VBG all/DT ./. The/DT giraffe/NN ,/, by/IN its/PRP$ lofty/JJ stature/NN ,/, much/JJ elongated/VBN neck/NN ,/, fore/NN legs/NNS ,/, head/NN and/CC tongue/NN ,/, has/VBZ its/PRP$ whole/JJ frame/NN beautifully/RB adapted/VBN for/IN browsing/VBG on/IN the/DT higher/JJR branches/NNS of/IN trees/NNS ./. It/PRP can/MD thus/RB obtain/VB food/NN beyond/IN the/DT reach/VB of/IN the/DT other/JJ Ungulata/NNP or/CC hoofed/VBN animals/NNS inhabiting/VBG the/DT same/JJ country/NN ;/: and/CC this/DT must/MD be/VB a/DT great/JJ advantage/NN to/TO it/PRP during/IN dearths/NNS ./. The/DT Niata/NNP cattle/NNS in/IN S/NNP ./. America/NNP show/NN us/PRP how/WRB small/JJ a/DT difference/NN in/IN structure/NN may/MD make/VB ,/, during/IN such/JJ periods/NNS ,/, a/DT great/JJ difference/NN in/IN preserving/VBG an/DT animal's/NNS life/NN ./. These/DT cattle/NNS can/MD browse/VB as/IN well/RB as/IN others/NNS on/IN grass/NN ,/, but/CC from/IN the/DT projection/NN of/IN the/DT lower/JJR jaw/NN they/PRP cannot/MD ,/, during/IN the/DT often/RB recurrent/JJ droughts/NNS ,/, browse/VB on/IN the/DT twigs/NNS of/IN trees/NNS ,/, reeds/NNS ,/, &c/NN ./. ,/, to/TO which/WDT food/NN the/DT common/JJ cattle/NNS and/CC horses/NNS are/VBP then/RB driven/VBN ;/: so/RB that/IN at/IN these/DT times/NNS the/DT Niatas/NNP perish/VB ,/, if/IN not/RB fed/VBN by/IN their/PRP$ owners/NNS ./. Before/IN coming/VBG to/TO Mr/NNP ./. Mivart's/NNP objections/NNS ,/, it/PRP may/MD be/VB well/RB to/TO explain/VB once/RB again/RB how/WRB natural/JJ selection/NN will/MD act/NN in/IN all/DT ordinary/JJ cases/NNS ./. Man/NN has/VBZ modified/VBN some/DT of/IN his/PRP$ animals/NNS ,/, without/IN necessarily/RB having/VBG attended/VBD to/TO special/JJ points/NNS of/IN structure/NN ,/, by/IN simply/RB preserving/VBG and/CC breeding/VBG from/IN the/DT fleetest/JJS individuals/NNS ,/, as/IN with/IN the/DT race/NN horse/NN and/CC greyhound/NN ,/, or/CC as/IN with/IN the/DT game/NN cock/NN ,/, by/IN breeding/VBG from/IN the/DT victorious/JJ birds/NNS ./. So/RB under/IN nature/NN with/IN the/DT nascent/JJ giraffe/NN the/DT individuals/NNS which/WDT were/VBD the/DT highest/JJS browsers/NNS ,/, and/CC were/VBD able/JJ during/IN dearths/NNS to/TO reach/VB even/RB an/DT inch/NN or/CC two/CD above/IN the/DT others/NNS ,/, will/MD often/RB have/VBP been/VBN preserved/VBN ;/: for/IN they/PRP will/MD have/VB roamed/VBD over/IN the/DT whole/JJ country/NN in/IN search/NN of/IN food/NN ./. That/DT the/DT individuals/NNS of/IN the/DT same/JJ species/NN often/RB differ/VBP slightly/RB in/IN the/DT relative/JJ lengths/NNS of/IN all/DT their/PRP$ parts/NNS may/MD be/VB seen/VBN in/IN many/JJ works/NNS of/IN natural/JJ history/NN ,/, in/IN which/WDT careful/JJ measurements/NNS are/VBP given/VBN ./. These/DT slight/JJ proportional/JJ differences/NNS ,/, due/JJ to/TO the/DT laws/NNS of/IN growth/NN and/CC variation/NN ,/, are/VBP not/RB of/IN the/DT slightest/JJS use/NN or/CC importance/NN to/TO most/RBS species/NN ./. But/CC it/PRP will/MD have/VB been/VBN otherwise/RB with/IN the/DT nascent/JJ giraffe/NN ,/, considering/VBG its/PRP$ probable/JJ habits/NNS of/IN life/NN ;/: for/IN those/DT individuals/NNS which/WDT had/VBD some/DT one/CD part/NN or/CC several/JJ parts/NNS of/IN their/PRP$ bodies/NNS rather/RB more/JJR elongated/VBN than/IN usual/JJ ,/, would/MD generally/RB have/VBP survived/VBD ./. These/DT will/MD have/VB intercrossed/VBN and/CC left/VBN offspring/NN ,/, either/DT inheriting/VBG the/DT same/JJ bodily/JJ peculiarities/NNS ,/, or/CC with/IN a/DT tendency/NN to/TO vary/VB again/RB in/IN the/DT same/JJ manner/NN ;/: whilst/NN the/DT individuals/NNS ,/, less/JJR favoured/VBN in/IN the/DT same/JJ respects/NNS ,/, will/MD have/VB been/VBN the/DT most/RBS liable/JJ to/TO perish/VB ./. We/PRP here/RB see/VB that/IN there/EX is/VBZ no/DT need/NN to/TO separate/JJ single/JJ pairs/NNS ,/, as/IN man/NN does/VBZ ,/, when/WRB he/PRP methodically/RB improves/VBZ a/DT breed/NN :/: natural/JJ selection/NN will/MD preserve/VB and/CC thus/RB separate/JJ all/DT the/DT superior/JJ individuals/NNS ,/, allowing/VBG them/PRP freely/RB to/TO intercross/NN ,/, and/CC will/MD destroy/VB all/DT the/DT inferior/JJ individuals/NNS ./. By/IN this/DT process/NN long/JJ continued/VBD ,/, which/WDT exactly/RB corresponds/VBZ with/IN what/WP I/PRP have/VBP called/VBN unconscious/JJ selection/NN by/IN man/NN ,/, combined/VBN no/DT doubt/NN in/IN a/DT most/RBS important/JJ manner/NN with/IN the/DT inherited/VBN effects/NNS of/IN the/DT increased/VBN use/NN of/IN parts/NNS ,/, it/PRP seems/VBZ to/TO me/PRP almost/RB certain/JJ that/IN an/DT ordinary/JJ hoofed/VBN quadruped/VBD might/MD be/VB converted/VBN into/IN a/DT giraffe/NN ./. To/TO this/DT conclusion/NN Mr/NNP ./. Mivart/NNP brings/VBZ forward/RB two/CD objections/NNS ./. One/CD is/VBZ that/IN the/DT increased/VBN size/NN of/IN the/DT body/NN would/MD obviously/RB require/VB an/DT increased/VBN supply/NN of/IN food/NN ,/, and/CC he/PRP considers/VBZ it/PRP as/IN "/" very/RB problematical/JJ whether/IN the/DT disadvantages/NNS thence/RB arising/VBG would/MD not/RB ,/, in/IN times/NNS of/IN scarcity/NN ,/, more/JJR than/IN counterbalance/VB the/DT advantages/NNS ./. "/" But/CC as/IN the/DT giraffe/NN does/VBZ actually/RB exist/VB in/IN large/JJ numbers/NNS in/IN S/NNP ./. Africa/NNP ,/, and/CC as/IN some/DT of/IN the/DT largest/JJS antelopes/NNS in/IN the/DT world/NN ,/, taller/JJR than/IN an/DT ox/NN ,/, abound/VBP there/EX ,/, why/WRB should/MD we/PRP doubt/NN that/IN ,/, as/IN far/RB as/IN size/NN is/VBZ concerned/VBN ,/, intermediate/JJ gradations/NNS could/MD formerly/RB have/VBP existed/VBD there/EX ,/, subjected/VBN as/IN now/RB to/TO severe/JJ dearths/NNS ./. Assuredly/RB the/DT being/VBG able/JJ to/TO reach/VB ,/, at/IN each/DT stage/NN of/IN increased/VBN size/NN ,/, to/TO a/DT supply/NN of/IN food/NN ,/, left/VBN untouched/JJ by/IN the/DT other/JJ hoofed/VBN quadrupeds/NNS of/IN the/DT country/NN ,/, would/MD have/VB been/VBN of/IN some/DT advantage/NN to/TO the/DT nascent/JJ giraffe/NN ./. Nor/CC must/MD we/PRP overlook/VB the/DT fact/NN ,/, that/IN increased/VBN bulk/NN would/MD act/NN as/IN a/DT protection/NN against/IN almost/RB all/DT beasts/NNS of/IN prey/NN excepting/VBG the/DT lion/NN ;/: and/CC against/IN this/DT animal/NN ,/, its/PRP$ tall/JJ neck/NN ,/, and/CC the/DT taller/JJR the/DT better/JJR ,/, would/MD ,/, as/IN Mr/NNP ./. Chauncey/NNP Wright/NNP has/VBZ remarked/VBN ,/, serve/VB as/IN a/DT watch/VB tower/NN ./. It/PRP is/VBZ from/IN this/DT cause/NN ,/, as/IN Sir/NNP S/NNP ./. Baker/NNP remarks/NNS ,/, that/IN no/DT animal/NN is/VBZ more/JJR difficult/JJ to/TO stalk/VBP than/IN the/DT giraffe/NN ./. This/DT animal/NN also/RB uses/VBZ its/PRP$ long/JJ neck/NN as/IN a/DT means/VBZ of/IN offence/NN or/CC defence/NN ,/, by/IN violently/RB swinging/VBG his/PRP$ head/NN armed/VBN with/IN stump/NN like/IN horns/NNS ./. The/DT preservation/NN of/IN each/DT species/NN can/MD rarely/RB be/VB determined/VBN by/IN any/DT one/CD advantage/NN ,/, but/CC by/IN the/DT union/NN of/IN all/DT ,/, great/JJ and/CC small/JJ ./. Mr/NNP ./. Mivart/NNP then/RB asks/VBZ (/( and/CC this/DT is/VBZ his/PRP$ second/JJ objection/NN )/SYM ,/, if/IN natural/JJ selection/NN be/VB so/RB potent/JJ ,/, and/CC if/IN high/JJ browsing/VBG be/VB so/RB great/JJ an/DT advantage/NN ,/, why/WRB has/VBZ not/RB any/DT other/JJ hoofed/VBN quadruped/VBD acquired/VBN a/DT long/JJ neck/NN and/CC lofty/JJ stature/NN ,/, besides/IN the/DT giraffe/NN ,/, and/CC ,/, in/IN a/DT lesser/JJR degree/NN ,/, the/DT camel/NN ,/, guanaeo/NN ,/, and/CC macrauchenia/NN ?/. Or/CC ,/, again/RB ,/, why/WRB has/VBZ not/RB any/DT member/NN of/IN the/DT group/NN acquired/VBN a/DT long/JJ proboscis/NN ?/. With/IN respect/NN to/TO S/NNP ./. Africa/NNP ,/, which/WDT was/VBD formerly/RB inhabited/VBN by/IN numerous/JJ herds/NNS of/IN the/DT giraffe/NN ,/, the/DT answer/NN is/VBZ not/RB difficult/JJ ,/, and/CC can/MD best/JJS be/VB given/VBN by/IN an/DT illustration/NN ./. In/IN every/DT meadow/NN in/IN England/NNP in/IN which/WDT trees/NNS grow/VB ,/, we/PRP see/VB the/DT lower/JJR branches/NNS trimmed/VBN or/CC planed/VBN to/TO an/DT exact/JJ level/NN by/IN the/DT browsing/VBG of/IN the/DT horses/NNS or/CC cattle/NNS ;/: and/CC what/WP advantage/NN would/MD it/PRP be/VB ,/, for/IN instance/NN ,/, to/TO sheep/NN ,/, if/IN kept/VBD there/EX ,/, to/TO acquire/VB slightly/RB longer/RB necks/NNS ?/. In/IN every/DT district/NN some/DT one/CD kind/NN of/IN animal/NN will/MD almost/RB certainly/RB be/VB able/JJ to/TO browse/VB higher/JJR than/IN the/DT others/NNS ;/: and/CC it/PRP is/VBZ almost/RB equally/RB certain/JJ that/IN this/DT one/CD kind/NN alone/RB could/MD have/VB its/PRP$ neck/NN elongated/VBN for/IN this/DT purpose/NN ,/, through/IN natural/JJ selection/NN and/CC the/DT effects/NNS of/IN increased/VBN use/NN ./. In/IN S/NNP ./. Africa/NNP the/DT competition/NN for/IN browsing/VBG on/IN the/DT higher/JJR branches/NNS of/IN the/DT acacias/NNS and/CC other/JJ trees/NNS must/MD be/VB between/IN giraffe/NN and/CC giraffe/NN ,/, and/CC not/RB with/IN the/DT other/JJ ungulate/VB animals/NNS ./. Why/WRB ,/, in/IN other/JJ quarters/NNS of/IN the/DT world/NN ,/, various/JJ animals/NNS belonging/VBG to/TO this/DT same/JJ order/NN have/VBP not/RB acquired/VBN either/DT an/DT elongated/VBN neck/NN or/CC a/DT proboscis/NN ,/, cannot/MD be/VB distinctly/RB answered/VBD ;/: but/CC it/PRP is/VBZ as/IN unreasonable/JJ to/TO expect/VB a/DT distinct/JJ answer/NN to/TO such/JJ a/DT question/NN ,/, as/IN why/WRB some/DT event/NN in/IN the/DT history/NN of/IN mankind/NN did/VBD not/RB occur/VB in/IN one/CD country/NN ,/, whilst/NN it/PRP did/VBD in/IN another/DT ./. We/PRP are/VBP ignorant/JJ with/IN respect/NN to/TO the/DT conditions/NNS which/WDT determine/VB the/DT numbers/NNS and/CC range/NN of/IN each/DT species/NN ;/: and/CC we/PRP cannot/MD even/RB conjecture/NN what/WP changes/NNS of/IN structure/NN would/MD be/VB favourable/JJ to/TO its/PRP$ increase/NN in/IN some/DT new/JJ country/NN ./. We/PRP can/MD ,/, however/RB ,/, see/VB in/IN a/DT general/JJ manner/NN that/IN various/JJ causes/NNS might/MD have/VB interfered/VBD with/IN the/DT development/NN of/IN a/DT long/JJ neck/NN or/CC proboscis/NN ./. To/TO reach/VB the/DT foliage/NN at/IN a/DT considerable/JJ height/NN (/( without/IN climbing/VBG ,/, for/IN which/WDT hoofed/VBN animals/NNS are/VBP singularly/RB ill/JJ constructed/VBN )/SYM implies/VBZ greatly/RB increased/VBN bulk/NN of/IN body/NN ;/: and/CC we/PRP know/VB that/IN some/DT areas/NNS support/NN singularly/RB few/JJ large/JJ quadrupeds/NNS ,/, for/IN instance/NN S/NNP ./. America/NNP ,/, though/IN it/PRP is/VBZ so/RB luxuriant/NN ;/: whilst/NN S/NNP ./. Africa/NNP abounds/VBZ with/IN them/PRP to/TO an/DT unparalleled/JJ degree/NN ./. Why/WRB this/DT should/MD be/VB so/RB ,/, we/PRP do/VBP not/RB know/VB ;/: nor/CC why/WRB the/DT later/RB tertiary/JJ periods/NNS should/MD have/VB been/VBN so/RB much/JJ more/JJR favourable/JJ for/IN their/PRP$ existence/NN than/IN the/DT present/JJ time/NN ./. Whatever/WDT the/DT causes/NNS may/MD have/VB been/VBN ,/, we/PRP can/MD see/VB that/IN certain/JJ districts/NNS and/CC times/NNS would/MD have/VB been/VBN much/JJ more/JJR favourable/JJ than/IN others/NNS for/IN the/DT development/NN of/IN so/RB large/JJ a/DT quadruped/VBD as/IN the/DT giraffe/NN ./. In/IN order/NN that/IN an/DT animal/NN should/MD acquire/VB some/DT structure/NN specially/RB and/CC largely/RB developed/VBN ,/, it/PRP is/VBZ almost/RB indispensable/JJ that/IN several/JJ other/JJ parts/NNS should/MD be/VB modified/VBN and/CC co/NN adapted/VBN ./. Although/IN every/DT part/NN of/IN the/DT body/NN varies/VBZ slightly/RB ,/, it/PRP does/VBZ not/RB follow/VB that/IN the/DT necessary/JJ parts/NNS should/MD always/RB vary/VBP in/IN the/DT right/NN direction/NN and/CC to/TO the/DT right/NN degree/NN ./. With/IN the/DT different/JJ species/NN of/IN our/PRP$ domesticated/VBN animals/NNS we/PRP know/VB that/IN the/DT parts/NNS vary/VBP in/IN a/DT different/JJ manner/NN and/CC degree/NN ;/: and/CC that/IN some/DT species/NN are/VBP much/JJ more/JJR variable/JJ than/IN others/NNS ./. Even/RB if/IN the/DT fitting/JJ variations/NNS did/VBD arise/VB ,/, it/PRP does/VBZ not/RB follow/VB that/IN natural/JJ selection/NN would/MD be/VB able/JJ to/TO act/NN on/IN them/PRP ,/, and/CC produce/VB a/DT structure/NN which/WDT apparently/RB would/MD be/VB beneficial/JJ to/TO the/DT species/NN ./. For/IN instance/NN ,/, if/IN the/DT number/NN of/IN individuals/NNS existing/VBG in/IN a/DT country/NN is/VBZ determined/VBN chiefly/RB through/IN destruction/NN by/IN beasts/NNS of/IN prey/NN ,/, by/IN external/JJ or/CC internal/JJ parasites/NNS ,/, &c/NN ./. ,/, as/IN seems/VBZ often/RB to/TO be/VB the/DT case/NN ,/, then/RB natural/JJ selection/NN will/MD be/VB able/JJ to/TO do/VB little/JJ ,/, or/CC will/MD be/VB greatly/RB retarded/JJ ,/, in/IN modifying/VBG any/DT particular/JJ structure/NN for/IN obtaining/VBG food/NN ./. Lastly/RB ,/, natural/JJ selection/NN is/VBZ a/DT slow/JJ process/NN ,/, and/CC the/DT same/JJ favourable/JJ conditions/NNS must/MD long/JJ endure/VB in/IN order/NN that/IN any/DT marked/VBN effect/NN should/MD thus/RB be/VB produced/VBN ./. Except/IN by/IN assigning/VBG such/JJ general/JJ and/CC vague/JJ reasons/NNS ,/, we/PRP cannot/MD explain/VB why/WRB ,/, in/IN many/JJ quarters/NNS of/IN the/DT world/NN ,/, hoofed/VBN quadrupeds/NNS have/VBP not/RB acquired/VBN much/JJ elongated/VBN necks/NNS or/CC other/JJ means/VBZ for/IN browsing/VBG on/IN the/DT higher/JJR branches/NNS of/IN trees/NNS ./. Objections/NNS of/IN the/DT same/JJ nature/NN as/IN the/DT foregoing/NN have/VBP been/VBN advanced/VBD by/IN man/NN writers/NNS ./. In/IN each/DT case/NN various/JJ causes/NNS ,/, besides/IN the/DT general/JJ ones/NNS just/RB indicated/VBD ,/, have/VBP probably/RB interfered/VBD with/IN the/DT acquisition/NN through/IN natural/JJ selection/NN of/IN structures/NNS ,/, which/WDT it/PRP is/VBZ thought/VBN would/MD be/VB beneficial/JJ to/TO certain/JJ species/NN ./. One/CD writer/NN asks/VBZ ,/, why/WRB has/VBZ not/RB the/DT ostrich/JJ acquired/VBN the/DT power/NN of/IN flight/NN ?/. But/CC a/DT moment's/NNS reflection/NN will/MD show/NN what/WP an/DT enormous/JJ supply/NN of/IN food/NN would/MD be/VB necessary/JJ to/TO give/VB to/TO this/DT bird/NN of/IN the/DT desert/NN force/NN to/TO move/NN its/PRP$ huge/JJ body/NN through/IN the/DT air/NN ./. Oceanic/NNP islands/NNS are/VBP inhabited/VBN by/IN bats/NNS and/CC seals/NNS ,/, but/CC by/IN no/DT terrestrial/JJ mammals/NNS ;/: yet/RB as/IN some/DT of/IN these/DT bats/NNS are/VBP peculiar/JJ species/NN ,/, they/PRP must/MD have/VB long/JJ inhabited/VBN their/PRP$ present/JJ homes/NNS ./. Therefore/RB Sir/NNP C/NN ./. Lyell/NNP asks/VBZ ,/, and/CC assigns/VBZ certain/JJ reasons/NNS in/IN answer/NN ,/, why/WRB have/VBP not/RB seals/NNS and/CC bats/NNS given/VBN birth/NN on/IN such/JJ islands/NNS to/TO forms/NNS fitted/VBN to/TO live/VB on/IN the/DT land/NN ?/. But/CC seals/NNS would/MD necessarily/RB be/VB first/JJ converted/VBN into/IN terrestrial/JJ carnivorous/JJ animals/NNS of/IN considerable/JJ size/NN ,/, and/CC bats/NNS into/IN terrestrial/JJ insectivorous/JJ animals/NNS ;/: for/IN the/DT former/JJ there/EX would/MD be/VB no/DT prey/NN ;/: for/IN the/DT bats/NNS ground/NN insects/NNS would/MD serve/VB as/IN food/NN ,/, but/CC these/DT would/MD already/RB be/VB largely/RB preyed/VBN on/IN by/IN the/DT reptiles/NNS or/CC birds/NNS ,/, which/WDT first/JJ colonise/NN and/CC abound/VBP on/IN most/RBS oceanic/JJ islands/NNS ./. Gradations/NNS of/IN structure/NN ,/, with/IN each/DT stage/NN beneficial/JJ to/TO a/DT changing/VBG species/NN ,/, will/MD be/VB favoured/VBN only/RB under/IN certain/JJ peculiar/JJ conditions/NNS ./. A/DT strictly/RB terrestrial/JJ animal/NN ,/, by/IN occasionally/RB hunting/NN for/IN food/NN in/IN shallow/JJ water/NN ,/, then/RB in/IN streams/NNS or/CC lakes/NNS ,/, might/MD at/IN last/JJ be/VB converted/VBN into/IN an/DT animal/NN so/RB thoroughly/RB aquatic/JJ as/IN to/TO brave/JJ the/DT open/JJ ocean/NN ./. But/CC seals/NNS would/MD not/RB find/VB on/IN oceanic/JJ islands/NNS the/DT conditions/NNS favourable/JJ to/TO their/PRP$ gradual/JJ reconversion/NN into/IN a/DT terrestrial/JJ form/NN ./. Bats/NNS ,/, as/IN formerly/RB shown/VBN ,/, probably/RB acquired/VBN their/PRP$ wings/NNS by/IN at/IN first/JJ gliding/VBG through/IN the/DT air/NN from/IN tree/NN to/TO tree/NN ,/, like/IN the/DT so/RB called/VBN flying/VBG squirrels/NNS ,/, for/IN the/DT sake/NN of/IN escaping/VBG from/IN their/PRP$ enemies/NNS ,/, or/CC for/IN avoiding/VBG falls/VBZ ;/: but/CC when/WRB the/DT power/NN of/IN true/JJ flight/NN had/VBD once/RB been/VBN acquired/VBN ,/, it/PRP would/MD never/RB be/VB reconverted/VBN back/RB ,/, at/IN least/JJS for/IN the/DT above/IN purposes/NNS ,/, into/IN the/DT less/JJR efficient/JJ power/NN of/IN gliding/VBG through/IN the/DT air/NN ./. Bats/NNS might/MD ,/, indeed/RB ,/, like/IN many/JJ birds/NNS ,/, have/VBP had/VBD their/PRP$ wings/NNS greatly/RB reduced/VBN in/IN size/NN ,/, or/CC completely/RB lost/VBD ,/, through/IN disuse/NN ;/: but/CC in/IN this/DT case/NN it/PRP would/MD be/VB necessary/JJ that/IN they/PRP should/MD first/JJ have/VBP acquired/VBN the/DT power/NN of/IN running/VBG quickly/RB on/IN the/DT ground/NN ,/, by/IN the/DT aid/NN of/IN their/PRP$ hind/JJ legs/NNS alone/RB ,/, so/RB as/IN to/TO compete/VB with/IN birds/NNS or/CC other/JJ ground/NN animals/NNS ;/: and/CC for/IN such/JJ a/DT change/NN a/DT bat/NN seems/VBZ singularly/RB ill/JJ fitted/VBN ./. These/DT conjectural/JJ remarks/NNS have/VBP been/VBN made/VBN merely/RB to/TO show/NN that/IN a/DT transition/NN of/IN structure/NN ,/, with/IN each/DT step/NN beneficial/JJ ,/, is/VBZ a/DT highly/RB complex/JJ affair/NN ;/: and/CC that/IN there/EX is/VBZ nothing/NN strange/JJ in/IN a/DT transition/NN not/RB having/VBG occurred/VBD in/IN any/DT particular/JJ case/NN ./. Lastly/RB ,/, more/JJR than/IN one/CD writer/NN has/VBZ asked/VBN ,/, why/WRB have/VBP some/DT animals/NNS had/VBD their/PRP$ mental/JJ powers/NNS more/JJR highly/RB developed/VBN than/IN others/NNS ,/, as/IN such/JJ development/NN would/MD be/VB advantageous/JJ to/TO an/DT ?/. Why/WRB have/VBP not/RB apes/NNS acquired/VBN the/DT intellectual/JJ powers/NNS of/IN man/NN ?/. Various/JJ causes/NNS could/MD be/VB assigned/VBN ;/: but/CC as/IN they/PRP are/VBP conjectural/JJ ,/, and/CC their/PRP$ relative/JJ probability/NN cannot/MD be/VB weighed/VBD ,/, it/PRP would/MD be/VB useless/JJ to/TO give/VB them/PRP ./. A/DT definite/JJ answer/NN to/TO the/DT latter/NN question/NN ought/MD not/RB to/TO be/VB expected/VBN ,/, seeing/VBG that/IN no/DT one/CD can/MD solve/VB the/DT simpler/JJR problem/NN why/WRB ,/, of/IN two/CD races/NNS of/IN savages/NNS ,/, one/CD has/VBZ risen/VBN higher/JJR in/IN the/DT scale/NN of/IN civilisation/NN than/IN the/DT other/JJ ;/: and/CC this/DT apparently/RB implies/VBZ increased/VBN brain/NN power/NN ./. We/PRP will/MD return/NN to/TO Mr/NNP ./. Mivart's/NNP other/JJ objections/NNS ./. Insects/NNS often/RB resemble/VB for/IN the/DT sake/NN of/IN protection/NN various/JJ objects/NNS ,/, such/JJ as/IN green/JJ or/CC decayed/JJ leaves/VBZ ,/, dead/JJ twigs/NNS ,/, bits/NNS of/IN lichen/NN ,/, flowers/NNS ,/, spines/NNS ,/, excrement/NN of/IN birds/NNS ,/, and/CC living/VBG insects/NNS ;/: but/CC to/TO this/DT latter/NN point/NN I/PRP shall/MD hereafter/RB recur/VB ./. The/DT resemblance/NN is/VBZ often/RB wonderfully/RB close/VB ,/, and/CC is/VBZ not/RB confined/VBN to/TO colour/NN ,/, but/CC extends/VBZ to/TO form/NN ,/, and/CC even/RB to/TO the/DT manner/NN in/IN which/WDT the/DT insects/NNS hold/VB themselves/PRP ./. The/DT caterpillars/NNS which/WDT project/NN motionless/JJ like/IN dead/JJ twigs/NNS from/IN the/DT bushes/NNS on/IN which/WDT they/PRP feed/NN ,/, offer/NN an/DT excellent/JJ instance/NN of/IN a/DT resemblance/NN of/IN this/DT kind/NN ./. The/DT cases/NNS of/IN the/DT imitation/NN of/IN such/JJ objects/NNS as/IN the/DT excrement/NN of/IN birds/NNS ,/, are/VBP rare/JJ and/CC exceptional/JJ ./. On/IN this/DT head/NN ,/, Mr/NNP ./. Mivart/NNP remarks/NNS ,/, "/" As/IN ,/, according/VBG to/TO Mr/NNP ./. Darwin's/NNP theory/NN ,/, there/EX is/VBZ a/DT constant/JJ tendency/NN to/TO indefinite/JJ variation/NN ,/, and/CC as/IN the/DT minute/NN incipient/JJ variations/NNS will/MD be/VB in/IN all/DT directions/NNS ,/, they/PRP must/MD tend/VB to/TO neutralise/NN each/DT other/JJ ,/, and/CC at/IN first/JJ to/TO form/NN such/JJ unstable/JJ modifications/NNS that/IN it/PRP is/VBZ difficult/JJ ,/, if/IN not/RB impossible/JJ ,/, to/TO see/VB how/WRB such/JJ indefinite/JJ oscillations/NNS of/IN infinitesimal/JJ beginnings/NNS can/MD ever/RB build/VB up/IN a/DT sufficiently/RB appreciable/JJ resemblance/NN to/TO a/DT leaf/NN ,/, bamboo/NN ,/, or/CC other/JJ object/NN ,/, for/IN Natural/NNP Selection/NN to/TO seize/VB upon/IN and/CC perpetuate/VB ./. "/" But/CC in/IN all/DT the/DT foregoing/NN cases/NNS the/DT insects/NNS in/IN their/PRP$ original/JJ state/NN no/DT doubt/NN presented/VBN some/DT rude/JJ and/CC accidental/JJ resemblance/NN to/TO an/DT object/NN commonly/RB found/VBD in/IN the/DT stations/NNS frequented/VBD by/IN them/PRP ./. Nor/CC is/VBZ this/DT at/IN all/DT improbable/JJ ,/, considering/VBG the/DT almost/RB infinite/JJ number/NN of/IN surrounding/VBG objects/NNS and/CC the/DT diversity/NN in/IN form/NN and/CC colour/NN of/IN the/DT hosts/NNS of/IN insects/NNS which/WDT exist/VB ./. As/IN some/DT rude/JJ resemblance/NN is/VBZ necessary/JJ for/IN the/DT first/JJ start/VB ,/, we/PRP can/MD understand/VB how/WRB it/PRP is/VBZ that/IN the/DT larger/JJR and/CC higher/JJR animals/NNS do/VBP not/RB (/( with/IN the/DT exception/NN ,/, as/IN far/RB as/IN I/PRP know/VB ,/, of/IN one/CD fish/NN )/SYM resemble/VB for/IN the/DT sake/NN of/IN protection/NN special/JJ objects/NNS ,/, but/CC only/RB the/DT surface/NN which/WDT commonly/RB surrounds/VBZ them/PRP ,/, and/CC this/DT chiefly/RB in/IN colour/NN ./. Assuming/VBG that/IN an/DT insect/NN originally/RB happened/VBD to/TO resemble/VB in/IN some/DT degree/NN a/DT dead/JJ twig/NN or/CC a/DT decayed/JJ leaf/NN ,/, and/CC that/IN it/PRP varied/VBN slightly/RB in/IN many/JJ ways/NNS ,/, then/RB all/DT the/DT variations/NNS which/WDT rendered/VBN the/DT insect/NN at/IN all/DT more/JJR like/IN any/DT such/JJ object/NN ,/, and/CC thus/RB favoured/VBN its/PRP$ escape/VB ,/, would/MD be/VB preserved/VBN ,/, whilst/NN other/JJ variations/NNS would/MD be/VB neglected/VBN and/CC ultimately/RB lost/VBD ;/: or/CC ,/, if/IN they/PRP rendered/VBN the/DT insect/NN at/IN all/DT less/JJR like/IN the/DT imitated/VBN object/NN ,/, they/PRP would/MD be/VB eliminated/VBN ./. There/EX would/MD indeed/RB be/VB force/NN in/IN Mr/NNP ./. Mivart's/NNP objection/NN ,/, if/IN we/PRP were/VBD to/TO attempt/NN to/TO account/NN for/IN the/DT above/IN resemblances/NNS ,/, independently/RB of/IN natural/JJ selection/NN ,/, through/IN mere/JJ fluctuating/VBG variability/NN ;/: but/CC as/IN the/DT case/NN stands/VBZ there/EX is/VBZ none/NN ./. Nor/CC can/MD I/PRP see/VB any/DT force/NN in/IN Mr/NNP ./. Mivart's/NNP difficulty/NN with/IN respect/NN to/TO "/" the/DT last/JJ touches/NNS of/IN perfection/NN in/IN the/DT mimicry/NN "/" ;/: as/IN in/IN the/DT case/NN given/VBN by/IN Mr/NNP ./. Wallace/NNP ,/, of/IN a/DT walking/VBG stick/VB insect/NN (/( Ceroxylus/NNP laceratus/JJ )/SYM ,/, which/WDT resembles/VBZ "/" a/DT stick/VB grown/VBN over/IN by/IN a/DT creeping/VBG moss/NN or/CC jungermannia/NN ./. "/" So/RB close/VB was/VBD this/DT resemblance/NN ,/, that/IN a/DT native/JJ Dyak/NNP maintained/VBN that/IN the/DT foliaceous/JJ excrescences/NNS were/VBD really/RB moss/NN ./. Insects/NNS are/VBP preyed/VBN on/IN by/IN birds/NNS and/CC other/JJ enemies/NNS ,/, whose/WP$ sight/NN is/VBZ probably/RB sharper/JJR than/IN ours/PRP ,/, and/CC every/DT grade/NN in/IN resemblance/NN which/WDT aided/VBN an/DT insect/NN to/TO escape/VB notice/NN or/CC detection/NN ,/, would/MD tend/VB towards/IN its/PRP$ preservation/NN ;/: and/CC the/DT more/JJR perfect/JJ the/DT resemblance/NN so/RB much/JJ the/DT better/JJR for/IN the/DT insect/NN ./. Considering/VBG the/DT nature/NN of/IN the/DT differences/NNS between/IN the/DT species/NN in/IN the/DT group/NN which/WDT includes/VBZ the/DT above/IN Ceroxylus/NNP ,/, there/EX is/VBZ nothing/NN improbable/JJ in/IN this/DT insect/NN having/VBG varied/VBN in/IN the/DT irregularities/NNS on/IN its/PRP$ surface/NN ,/, and/CC in/IN these/DT having/VBG become/VB more/JJR or/CC less/JJR green/JJ coloured/JJ ;/: for/IN in/IN every/DT group/NN the/DT characters/NNS which/WDT differ/VBP in/IN the/DT several/JJ species/NN are/VBP the/DT most/RBS apt/JJ to/TO vary/VB ,/, whilst/NN the/DT generic/JJ characters/NNS ,/, or/CC those/DT common/JJ to/TO all/DT the/DT species/NN ,/, are/VBP the/DT most/RBS constant/JJ ./. The/DT Greenland/NNP whale/NN is/VBZ one/CD of/IN the/DT most/RBS wonderful/JJ animals/NNS in/IN the/DT world/NN ,/, and/CC the/DT baleen/NN ,/, or/CC whale/NN bone/NN ,/, one/CD of/IN its/PRP$ greatest/JJS peculiarities/NNS ./. The/DT baleen/NN consists/VBZ of/IN a/DT row/NN ,/, on/IN each/DT side/NN of/IN the/DT upper/JJ jaw/NN ,/, of/IN about/IN 300/CD plates/NNS or/CC laminae/NN ,/, which/WDT stand/VB close/VB together/RB transversely/RB to/TO the/DT longer/RB axis/NN of/IN the/DT mouth/NN ./. Within/IN the/DT main/JJ row/NN there/EX are/VBP some/DT subsidiary/NN rows/NNS ./. The/DT extremities/NNS and/CC inner/JJ margins/NNS of/IN all/DT the/DT plates/NNS are/VBP frayed/JJ into/IN stiff/JJ bristles/VBZ ,/, which/WDT clothe/VB the/DT whole/JJ gigantic/JJ palate/NN ,/, and/CC serve/VB to/TO strain/NN or/CC sift/VB the/DT water/NN ,/, and/CC thus/RB to/TO secure/VB the/DT minute/NN prey/NN on/IN which/WDT these/DT great/JJ animals/NNS subsist/VB ./. The/DT middle/NN and/CC longest/JJS lamina/NN in/IN the/DT Greenland/NNP whale/NN is/VBZ ten/CD ,/, twelve/CD ,/, or/CC even/RB fifteen/CD feet/NNS in/IN length/NN ;/: but/CC in/IN the/DT different/JJ species/NN of/IN cetaceans/NNS there/EX are/VBP gradations/NNS in/IN length/NN ;/: the/DT middle/NN lamina/NN being/VBG in/IN one/CD species/NN ,/, according/VBG to/TO Scoresby/NNP ,/, four/CD feet/NNS ,/, in/IN another/DT three/CD ,/, in/IN another/DT eighteen/CD inches/NNS ,/, and/CC in/IN the/DT Balaenoptera/NNP rostrata/NN only/RB about/IN nine/CD inches/NNS in/IN length/NN ./. The/DT quality/NN of/IN the/DT whale/NN bone/NN also/RB differs/VBZ in/IN the/DT different/JJ species/NN ./. With/IN respect/NN to/TO the/DT baleen/NN ,/, Mr/NNP ./. Mivart/NNP remarks/NNS that/IN if/IN it/PRP "/" had/VBD once/RB attained/VBD such/JJ a/DT size/NN and/CC development/NN as/IN to/TO be/VB at/IN all/DT useful/JJ ,/, then/RB its/PRP$ preservation/NN and/CC augmentation/NN within/IN serviceable/JJ limits/NNS would/MD be/VB promoted/VBN by/IN natural/JJ selection/NN alone/RB ./. But/CC how/WRB to/TO obtain/VB the/DT beginning/VBG of/IN such/JJ useful/JJ development/NN ?/. "/" In/IN answer/NN ,/, it/PRP may/MD be/VB asked/VBD ,/, why/WRB should/MD not/RB the/DT early/JJ progenitors/NNS of/IN the/DT whales/NNS with/IN baleen/NN have/VBP possessed/VBD a/DT mouth/NN constructed/VBN something/NN like/IN the/DT lamellated/VBN beak/NN of/IN a/DT duck/NN ?/. Ducks/NNP ,/, like/IN whales/NNS ,/, subsist/VB by/IN sifting/NN the/DT mud/NN and/CC water/NN ;/: and/CC the/DT family/NN has/VBZ sometimes/RB been/VBN called/VBN Criblatores/NNP ,/, or/CC sifters/NNS ./. I/PRP hope/NN that/IN I/PRP may/MD not/RB be/VB misconstrued/VBN into/IN saying/VBG that/IN the/DT progenitors/NNS of/IN whales/NNS did/VBD actually/RB possess/VBP mouths/NNS lamellated/VBN like/IN the/DT beak/NN of/IN a/DT duck/NN ./. I/PRP wish/VBP only/RB to/TO show/NN that/IN this/DT is/VBZ not/RB incredible/JJ ,/, and/CC that/IN the/DT immense/JJ plates/NNS of/IN baleen/NN in/IN the/DT Greenland/NNP whale/NN might/MD have/VB been/VBN developed/VBN from/IN such/JJ lamellae/NN by/IN finely/RB graduated/VBN steps/NNS ,/, each/DT of/IN service/NN to/TO its/PRP$ possessor/NN ./. The/DT beak/NN of/IN a/DT shoveller/NN duck/NN (/( Spatula/NNP elypedta/NN )/SYM is/VBZ a/DT more/JJR beautiful/JJ and/CC complex/JJ structure/NN than/IN the/DT mouth/NN of/IN a/DT whale/NN ./. The/DT upper/JJ mandible/JJ is/VBZ furnished/VBN on/IN each/DT side/NN (/( in/IN the/DT specimen/NN examined/VBD by/IN me/PRP )/SYM with/IN a/DT row/NN or/CC comb/NN formed/VBN of/IN 188/CD thin/JJ ,/, elastic/JJ lamellae/NN ,/, obliquely/RB bevelled/VBN so/RB as/IN to/TO be/VB pointed/VBD ,/, and/CC placed/VBN transversely/RB to/TO the/DT longer/RB axis/NN of/IN the/DT mouth/NN ./. They/PRP arise/VB from/IN the/DT palate/NN ,/, and/CC are/VBP attached/VBN by/IN flexible/JJ membrane/NN to/TO the/DT sides/NNS of/IN the/DT mandible/JJ ./. Those/DT standing/VBG towards/IN the/DT middle/NN are/VBP the/DT longest/JJS ,/, being/VBG about/IN one/CD third/JJ of/IN an/DT inch/NN in/IN length/NN ,/, and/CC they/PRP project/NN ./. 14/CD of/IN an/DT inch/NN beneath/IN the/DT edge/NN ./. At/IN their/PRP$ bases/NNS there/EX is/VBZ a/DT short/JJ subsidiary/NN row/NN of/IN obliquely/RB transverse/JJ lamellae/NN ./. In/IN these/DT several/JJ respects/NNS they/PRP resemble/VB the/DT plates/NNS of/IN baleen/NN in/IN the/DT mouth/NN of/IN a/DT whale/NN ./. But/CC towards/IN the/DT extremity/NN of/IN the/DT beak/NN they/PRP differ/VBP much/JJ ,/, as/IN they/PRP project/NN inwards/NNS ,/, instead/RB of/IN straight/JJ downwards/NNS ./. The/DT entire/JJ head/NN of/IN the/DT shoveller/NN ,/, though/IN incomparably/RB less/JJR bulky/JJ ,/, is/VBZ about/IN one/CD eighteenth/JJ of/IN the/DT length/NN of/IN the/DT head/NN of/IN a/DT moderately/RB large/JJ Balaenoptera/NNP rostrata/NN ,/, in/IN which/WDT species/NN the/DT baleen/NN is/VBZ only/RB nine/CD inches/NNS long/JJ ;/: so/RB that/IN if/IN we/PRP were/VBD to/TO make/VB the/DT head/NN of/IN the/DT shoveller/NN as/IN long/JJ as/IN that/IN of/IN the/DT Balaenoptera/NNP ,/, the/DT lamellae/NN would/MD be/VB six/CD inches/NNS in/IN length/NN ,/, that/IN is/VBZ ,/, two/CD thirds/NNS of/IN the/DT length/NN of/IN the/DT baleen/NN in/IN this/DT species/NN of/IN whale/NN ./. The/DT lower/JJR mandible/JJ of/IN the/DT shoveller/NN duck/NN is/VBZ furnished/VBN with/IN lamellae/NN of/IN equal/JJ length/NN with/IN those/DT above/IN ,/, but/CC finer/JJR ;/: and/CC in/IN being/VBG thus/RB furnished/VBN it/PRP differs/VBZ conspicuously/RB from/IN the/DT lower/JJR jaw/NN of/IN a/DT whale/NN ,/, which/WDT is/VBZ destitute/JJ of/IN baleen/NN ./. On/IN the/DT other/JJ hand/NN the/DT extremities/NNS of/IN these/DT lower/JJR lamellae/NN are/VBP frayed/JJ into/IN fine/JJ bristly/RB points/NNS ,/, so/RB that/IN they/PRP thus/RB curiously/RB resemble/VB the/DT plates/NNS of/IN baleen/NN ./. In/IN the/DT genus/NN Prion/NNP ,/, a/DT member/NN of/IN the/DT distinct/JJ family/NN of/IN the/DT petrels/NNS ,/, the/DT upper/JJ mandible/JJ alone/RB is/VBZ furnished/VBN with/IN lamellae/NN ,/, which/WDT are/VBP well/RB developed/VBN and/CC project/NN beneath/IN the/DT margin/NN ;/: so/RB that/IN the/DT beak/NN of/IN this/DT bird/NN resembles/VBZ in/IN this/DT respect/NN the/DT mouth/NN of/IN a/DT whale/NN ./. From/IN the/DT highly/RB developed/VBN structure/NN of/IN the/DT shoveller's/NNS beak/NN we/PRP may/MD proceed/VB (/( as/IN I/PRP have/VBP learnt/NN from/IN information/NN and/CC specimens/NNS sent/VBD to/TO me/PRP by/IN Mr/NNP ./. Salvin/NNP )/SYM ,/, without/IN any/DT great/JJ break/VB ,/, as/IN far/RB as/IN fitness/NN for/IN sifting/NN is/VBZ concerned/VBN ,/, through/IN the/DT beak/NN of/IN the/DT Merganetta/NNP armata/NNP ,/, and/CC in/IN some/DT respects/NNS through/IN that/IN of/IN the/DT Aix/NNP sponsa/NN ,/, to/TO the/DT beak/NN of/IN the/DT common/JJ duck/NN ./. In/IN this/DT latter/NN species/NN ,/, the/DT lamellae/NN are/VBP much/JJ coarser/NN than/IN in/IN the/DT shoveller/NN ,/, and/CC are/VBP firmly/RB attached/VBN to/TO the/DT sides/NNS of/IN the/DT mandible/JJ ;/: they/PRP are/VBP only/RB about/IN 50/CD in/IN number/NN on/IN each/DT side/NN ,/, and/CC do/VBP not/RB project/NN at/IN all/DT beneath/IN the/DT margin/NN ./. They/PRP are/VBP square/NN topped/VBD ,/, and/CC are/VBP edged/VBD with/IN translucent/JJ hardish/JJ tissue/NN ,/, as/IN if/IN for/IN crushing/VBG food/NN ./. The/DT edges/NNS of/IN the/DT lower/JJR mandible/JJ are/VBP crossed/VBD by/IN numerous/JJ fine/JJ ridges/NNS ,/, which/WDT project/NN very/RB little/JJ ./. Although/IN the/DT beak/NN is/VBZ thus/RB very/RB inferior/JJ as/IN a/DT sifter/NN to/TO that/IN of/IN the/DT shoveller/NN ,/, yet/RB this/DT bird/NN ,/, as/IN every/DT one/CD knows/VBZ ,/, constantly/RB uses/VBZ it/PRP for/IN this/DT purpose/NN ./. There/EX are/VBP other/JJ species/NN ,/, as/IN I/PRP hear/VB from/IN Mr/NNP ./. Salvin/NNP ,/, in/IN which/WDT the/DT lamellae/NN are/VBP considerably/RB less/JJR developed/VBN than/IN in/IN the/DT common/JJ duck/NN ;/: but/CC I/PRP do/VBP not/RB know/VB whether/IN they/PRP use/NN their/PRP$ beaks/NNS for/IN sifting/NN the/DT water/NN ./. Turning/VBG to/TO another/DT group/NN of/IN the/DT same/JJ family/NN :/: in/IN the/DT Egyptian/JJ goose/NN (/( Chenalopex/NNP )/SYM the/DT beak/NN closely/RB resembles/VBZ that/IN of/IN the/DT common/JJ ducks/NNS ;/: but/CC the/DT lamellae/NN are/VBP not/RB so/RB numerous/JJ ,/, nor/CC so/RB distinct/JJ from/IN each/DT other/JJ ,/, nor/CC do/VBP they/PRP project/NN so/RB much/JJ inwards/NNS ;/: yet/RB this/DT goose/NN ,/, as/IN I/PRP am/VBP informed/VBN by/IN Mr/NNP ./. E/NN ./. Bartlett/NNP ,/, "/" uses/VBZ its/PRP$ bill/NN like/IN a/DT duck/NN by/IN throwing/VBG the/DT water/NN out/IN at/IN the/DT corners/NNS ./. "/" Its/PRP$ chief/JJ food/NN ,/, however/RB ,/, is/VBZ grass/NN ,/, which/WDT it/PRP crops/NNS like/IN the/DT common/JJ goose/NN ./. In/IN this/DT latter/NN bird/NN ,/, the/DT lamellae/NN of/IN the/DT upper/JJ mandible/JJ are/VBP much/JJ coarser/NN than/IN in/IN the/DT common/JJ duck/NN ,/, almost/RB confluent/JJ ,/, about/IN 27/CD in/IN number/NN on/IN each/DT side/NN ,/, and/CC terminating/VBG upwards/RB in/IN teeth/NNS like/IN knobs/NNS ./. The/DT palate/NN is/VBZ also/RB covered/VBN with/IN hard/JJ rounded/VBN knobs/NNS ./. The/DT edges/NNS of/IN the/DT lower/JJR mandible/JJ are/VBP serrated/VBN with/IN teeth/NNS much/JJ more/JJR prominent/JJ ,/, coarser/NN ,/, and/CC sharper/JJR than/IN in/IN the/DT duck/NN ./. The/DT common/JJ goose/NN does/VBZ not/RB sift/VB the/DT water/NN ,/, but/CC uses/VBZ its/PRP$ beak/NN exclusively/RB for/IN tearing/VBG or/CC cutting/VBG herbage/NN ,/, for/IN which/WDT purpose/NN it/PRP is/VBZ so/RB well/RB fitted/VBN ,/, that/IN it/PRP can/MD crop/NN grass/NN closer/JJR than/IN almost/RB any/DT other/JJ animal/NN ./. There/EX are/VBP other/JJ species/NN of/IN geese/NNS ,/, as/IN I/PRP hear/VB from/IN Mr/NNP ./. Bartlett/NNP ,/, in/IN which/WDT the/DT lamellae/NN are/VBP less/JJR developed/VBN than/IN in/IN the/DT common/JJ goose/NN ./. We/PRP thus/RB see/VB that/IN a/DT member/NN of/IN the/DT duck/NN family/NN ,/, with/IN a/DT beak/NN constructed/VBN like/IN that/IN of/IN the/DT common/JJ goose/NN and/CC adapted/VBN solely/RB for/IN grazing/VBG ,/, or/CC even/RB a/DT member/NN with/IN a/DT beak/NN having/VBG less/JJR well/RB developed/VBN lamellae/NN ,/, might/MD be/VB converted/VBN by/IN small/JJ changes/NNS into/IN a/DT species/NN like/IN the/DT Egyptian/JJ goose/NN ,/, this/DT into/IN one/CD like/IN the/DT common/JJ duck/NN ,/, and/CC ,/, lastly/RB ,/, into/IN one/CD like/IN the/DT shoveller/NN ,/, provided/VBN with/IN a/DT beak/NN almost/RB exclusively/RB adapted/VBN for/IN sifting/NN the/DT water/NN ;/: for/IN this/DT bird/NN could/MD hardly/RB use/NN any/DT part/NN of/IN its/PRP$ beak/NN ,/, except/IN the/DT hooked/VBN tip/NN ,/, for/IN seizing/VBG or/CC tearing/VBG solid/JJ food/NN ./. The/DT beak/NN of/IN a/DT goose/NN ,/, as/IN I/PRP may/MD add/VB ,/, might/MD also/RB be/VB converted/VBN by/IN small/JJ changes/NNS into/IN one/CD provided/VBN with/IN prominent/JJ ,/, recurved/VBN teeth/NNS ,/, like/IN those/DT of/IN the/DT merganser/NN (/( a/DT member/NN of/IN the/DT same/JJ family/NN )/SYM ,/, serving/VBG for/IN the/DT widely/RB different/JJ purpose/NN of/IN securing/VBG live/VB fish/NN ./. Returning/VBG to/TO the/DT whales/NNS :/: the/DT Hyperoodon/NNP bidens/NNS is/VBZ destitute/JJ of/IN true/JJ teeth/NNS in/IN an/DT efficient/JJ condition/NN ,/, but/CC its/PRP$ palate/NN is/VBZ roughened/VBN ,/, according/VBG to/TO Lacepide/NNP ,/, with/IN small/JJ ,/, unequal/JJ ,/, hard/JJ points/NNS of/IN horn/NN ./. There/EX is/VBZ ,/, therefore/RB ,/, nothing/NN improbable/JJ in/IN supposing/VBG that/IN some/DT early/JJ cetacean/NN form/NN was/VBD provided/VBN with/IN similar/JJ points/NNS of/IN horn/NN on/IN the/DT palate/NN ,/, but/CC rather/RB more/JJR regularly/RB placed/VBN ,/, and/CC which/WDT ,/, like/IN the/DT knobs/NNS on/IN the/DT beak/NN of/IN the/DT goose/NN ,/, aided/VBN it/PRP in/IN seizing/VBG or/CC tearing/VBG its/PRP$ food/NN ./. If/IN so/RB ,/, it/PRP will/MD hardly/RB be/VB denied/VBN that/IN the/DT points/NNS might/MD have/VB been/VBN converted/VBN through/IN variation/NN and/CC natural/JJ selection/NN into/IN lamellae/NN as/IN well/RB developed/VBN as/IN those/DT of/IN the/DT Egyptian/JJ goose/NN ,/, in/IN which/WDT case/NN they/PRP would/MD have/VB been/VBN used/VBN both/DT for/IN seizing/VBG objects/NNS and/CC for/IN sifting/NN the/DT water/NN ;/: then/RB into/IN lamellae/NN like/IN those/DT of/IN the/DT domestic/JJ duck/NN ;/: and/CC so/RB onwards/RB ,/, until/IN they/PRP became/VBD as/IN well/RB constructed/VBN as/IN those/DT of/IN the/DT shoveller/NN ,/, in/IN which/WDT case/NN they/PRP would/MD have/VB served/VBN exclusively/RB as/IN a/DT sifting/NN apparatus/NN ./. From/IN this/DT stage/NN ,/, in/IN which/WDT the/DT lamellae/NN would/MD be/VB two/CD thirds/NNS of/IN the/DT length/NN of/IN the/DT plates/NNS of/IN baleen/NN in/IN the/DT Balaenoptera/NNP rostrata/NN ,/, gradations/NNS ,/, which/WDT may/MD be/VB observed/VBN in/IN still/RB existing/VBG cetaceans/NNS ,/, lead/VB us/PRP onwards/RB to/TO the/DT enormous/JJ plates/NNS of/IN baleen/NN in/IN the/DT Greenland/NNP whale/NN ./. Nor/CC is/VBZ there/EX the/DT least/JJS reason/NN to/TO doubt/NN that/IN each/DT step/NN in/IN this/DT scale/NN might/MD have/VB been/VBN as/IN serviceable/JJ to/TO certain/JJ ancient/JJ cetaceans/NNS ,/, with/IN the/DT functions/NNS of/IN the/DT parts/NNS slowly/RB changing/VBG during/IN the/DT progress/NN of/IN development/NN ,/, as/IN are/VBP the/DT gradations/NNS in/IN the/DT beaks/NNS of/IN the/DT different/JJ existing/VBG members/NNS of/IN the/DT duck/NN family/NN ./. We/PRP should/MD bear/VB in/IN mind/NN that/IN each/DT species/NN of/IN duck/NN is/VBZ subjected/VBN to/TO a/DT severe/JJ struggle/NN for/IN existence/NN ,/, and/CC that/IN the/DT structure/NN of/IN every/DT part/NN of/IN its/PRP$ frame/NN must/MD be/VB well/RB adapted/VBN to/TO its/PRP$ conditions/NNS of/IN life/NN ./. The/DT Pleuronectidae/NNP ,/, or/CC flat/JJ fish/NN ,/, are/VBP remarkable/JJ for/IN their/PRP$ asymmetrical/JJ bodies/NNS ./. They/PRP rest/NN on/IN one/CD side/NN ,/, in/IN the/DT greater/JJR number/NN of/IN species/NN on/IN the/DT left/VBN ,/, but/CC in/IN some/DT on/IN the/DT right/NN side/NN ;/: and/CC occasionally/RB reversed/VBD adult/NN specimens/NNS occur/VB ./. The/DT lower/JJR ,/, or/CC resting/VBG surface/NN ,/, resembles/VBZ at/IN first/JJ sight/NN the/DT ventral/JJ surface/NN of/IN an/DT ordinary/JJ fish/NN :/: it/PRP is/VBZ of/IN a/DT white/JJ colour/NN ,/, less/JJR developed/VBN in/IN many/JJ ways/NNS than/IN the/DT upper/JJ side/NN ,/, with/IN the/DT lateral/JJ fins/NNS often/RB of/IN smaller/JJR size/NN ./. But/CC the/DT eyes/NNS offer/NN the/DT most/RBS remarkable/JJ peculiarity/NN ;/: for/IN they/PRP are/VBP both/DT placed/VBN on/IN the/DT upper/JJ side/NN of/IN the/DT head/NN ./. During/IN early/JJ youth/NN ,/, however/RB ,/, they/PRP stand/VB opposite/JJ to/TO each/DT other/JJ ,/, and/CC the/DT whole/JJ body/NN is/VBZ then/RB symmetrical/JJ ,/, with/IN both/DT sides/NNS equally/RB coloured/JJ ./. Soon/RB the/DT eye/NN proper/JJ to/TO the/DT lower/JJR side/NN begins/VBZ to/TO glide/VB slowly/RB round/NN the/DT head/NN to/TO the/DT upper/JJ side/NN ;/: but/CC does/VBZ not/RB pass/VB right/NN through/IN the/DT skull/NN ,/, as/IN was/VBD formerly/RB thought/VBD to/TO be/VB the/DT case/NN ./. It/PRP is/VBZ obvious/JJ that/IN unless/IN the/DT lower/JJR eye/NN did/VBD thus/RB travel/NN round/NN ,/, it/PRP could/MD not/RB be/VB used/VBN by/IN the/DT fish/NN whilst/NN lying/VBG in/IN its/PRP$ habitual/JJ position/NN on/IN one/CD side/NN ./. The/DT lower/JJR eye/NN would/MD ,/, also/RB ,/, have/VBP been/VBN liable/JJ to/TO be/VB abraded/VBN by/IN the/DT sandy/JJ bottom/NN ./. That/DT the/DT Pleuronectidae/NNP are/VBP admirably/RB adapted/VBN by/IN their/PRP$ flattened/VBN and/CC asymmetrical/JJ structure/NN for/IN their/PRP$ habits/NNS of/IN life/NN ,/, is/VBZ manifest/JJ from/IN several/JJ species/NN ,/, such/JJ as/IN soles/NNS ,/, flounders/VBZ ,/, &c/NN ./. ,/, being/VBG extremely/RB common/JJ ./. The/DT chief/JJ advantages/NNS thus/RB gained/VBD seem/VB to/TO be/VB protection/NN from/IN their/PRP$ enemies/NNS ,/, and/CC facility/NN for/IN feeding/VBG on/IN the/DT ground/NN ./. The/DT different/JJ members/NNS ,/, however/RB ,/, of/IN the/DT family/NN present/JJ ,/, as/IN Schiodte/NNP remarks/NNS ,/, "/" a/DT long/JJ series/NN of/IN forms/NNS exhibiting/VBG a/DT gradual/JJ transition/NN from/IN Hippoglossus/NNP pinguis/NN ,/, which/WDT does/VBZ not/RB in/IN any/DT considerable/JJ degree/NN alter/VB the/DT shape/NN in/IN which/WDT it/PRP leaves/VBZ the/DT ovum/NN ,/, to/TO the/DT soles/NNS ,/, which/WDT are/VBP entirely/RB thrown/VBN to/TO one/CD side/NN ./. "/" Mr/NNP ./. Mivart/NNP has/VBZ taken/VBN up/IN this/DT case/NN ,/, and/CC remarks/NNS that/IN a/DT sudden/JJ spontaneous/JJ transformation/NN in/IN the/DT position/NN of/IN the/DT eyes/NNS is/VBZ hardly/RB conceivable/JJ ,/, in/IN which/WDT I/PRP quite/RB agree/VB with/IN him/PRP ./. He/PRP then/RB adds/VBZ :/: "/" If/IN the/DT transit/NN was/VBD gradual/JJ ,/, then/RB how/WRB such/JJ transit/NN of/IN one/CD eye/NN a/DT minute/NN fraction/NN of/IN the/DT journey/NN towards/IN the/DT other/JJ side/NN of/IN the/DT head/NN could/MD benefit/NN the/DT individual/JJ is/VBZ ,/, indeed/RB ,/, far/RB from/IN clear/JJ ./. It/PRP seems/VBZ ,/, even/RB ,/, that/IN such/JJ an/DT incipient/JJ transformation/NN must/MD rather/RB have/VBP been/VBN injurious/JJ ./. "/" But/CC he/PRP might/MD have/VB found/VBD an/DT answer/NN to/TO this/DT objection/NN in/IN the/DT excellent/JJ observations/NNS published/VBN in/IN 1867/CD by/IN Malm/NNP ./. The/DT Pleuronectidae/NNP whilst/NN very/RB young/JJ and/CC still/RB symmetrical/JJ ,/, with/IN their/PRP$ eyes/NNS standing/VBG on/IN opposite/JJ sides/NNS of/IN the/DT head/NN ,/, cannot/MD long/JJ retain/VB a/DT vertical/JJ position/NN ,/, owing/JJ to/TO the/DT excessive/JJ depth/NN of/IN their/PRP$ bodies/NNS ,/, the/DT small/JJ size/NN of/IN their/PRP$ lateral/JJ fins/NNS ,/, and/CC to/TO their/PRP$ being/VBG destitute/JJ of/IN a/DT swimbladder/NN ./. Hence/RB soon/RB growing/VBG tired/VBN ,/, they/PRP fall/NN to/TO the/DT bottom/NN on/IN one/CD side/NN ./. Whilst/NNP thus/RB at/IN rest/NN they/PRP often/RB twist/NN ,/, as/IN Malm/NNP observed/VBN ,/, the/DT lower/JJR eye/NN upwards/RB ,/, to/TO see/VB above/IN them/PRP ;/: and/CC they/PRP do/VBP this/DT so/RB vigorously/RB that/IN the/DT eye/NN is/VBZ pressed/VBN hard/JJ against/IN the/DT upper/JJ part/NN of/IN the/DT orbit/NN ./. The/DT forehead/NN between/IN the/DT eyes/NNS consequently/RB becomes/VBZ ,/, as/IN could/MD be/VB plainly/RB seen/VBN ,/, temporarily/RB contracted/VBD in/IN breadth/NN ./. On/IN one/CD occasion/NN Malm/NNP saw/VBD a/DT young/JJ fish/NN raise/VB and/CC depress/VB the/DT lower/JJR eye/NN through/IN an/DT angular/JJ distance/NN of/IN about/IN seventy/CD degrees/NNS ./. We/PRP should/MD remember/VB that/IN the/DT skull/NN at/IN this/DT early/JJ age/NN is/VBZ cartilaginous/JJ and/CC flexible/JJ ,/, so/RB that/IN it/PRP readily/RB yields/NNS to/TO muscular/JJ action/NN ./. It/PRP is/VBZ also/RB known/VBN with/IN the/DT higher/JJR animals/NNS ,/, even/RB after/IN early/JJ youth/NN ,/, that/IN the/DT skull/NN yields/NNS and/CC is/VBZ altered/VBN in/IN shape/NN ,/, if/IN the/DT skin/NN or/CC muscles/NNS be/VB permanently/RB contracted/VBD through/IN disease/NN or/CC some/DT accident/NN ./. With/IN long/JJ eared/JJ rabbits/NNS ,/, if/IN one/CD ear/NN lops/NNS forwards/RB and/CC downwards/NNS ,/, its/PRP$ weight/NN drags/VBZ forward/RB all/DT the/DT bones/NNS of/IN the/DT skull/NN on/IN the/DT same/JJ side/NN ,/, of/IN which/WDT I/PRP have/VBP given/VBN a/DT figure/NN ./. Malm/NNP states/NNS that/IN the/DT newly/RB hatched/VBN young/JJ of/IN perches/NNS ,/, salmon/NN ,/, and/CC several/JJ other/JJ symmetrical/JJ fishes/NNS ,/, have/VBP the/DT habit/NN of/IN occasionally/RB resting/VBG on/IN one/CD side/NN at/IN the/DT bottom/NN ;/: and/CC he/PRP has/VBZ observed/VBN that/IN they/PRP often/RB then/RB strain/NN their/PRP$ lower/JJR eyes/NNS so/RB as/IN to/TO look/VB upwards/RB ;/: and/CC their/PRP$ skulls/NNS are/VBP thus/RB rendered/VBN rather/RB crooked/JJ ./. These/DT fishes/NNS ,/, however/RB ,/, are/VBP soon/RB able/JJ to/TO hold/VB themselves/PRP in/IN a/DT vertical/JJ position/NN ,/, and/CC no/DT permanent/JJ effect/NN is/VBZ thus/RB produced/VBN ./. With/IN the/DT Pleuronectidae/NNP ,/, on/IN the/DT other/JJ hand/NN ,/, the/DT older/JJR they/PRP grow/VB the/DT more/JJR habitually/RB they/PRP rest/NN on/IN one/CD side/NN ,/, owing/JJ to/TO the/DT increasing/VBG flatness/NN of/IN their/PRP$ bodies/NNS ,/, and/CC a/DT permanent/JJ effect/NN is/VBZ thus/RB produced/VBN on/IN the/DT form/NN of/IN the/DT head/NN ,/, and/CC on/IN the/DT position/NN of/IN the/DT eyes/NNS ./. Judging/VBG from/IN analogy/NN ,/, the/DT tendency/NN to/TO distortion/NN would/MD no/DT doubt/NN be/VB increased/VBN through/IN the/DT principle/NN of/IN inheritance/NN ./. Schiodte/NNP believes/VBZ ,/, in/IN opposition/NN to/TO some/DT other/JJ naturalists/NNS ,/, that/IN the/DT Pleuronectidae/NNP are/VBP not/RB quite/RB symmetrical/JJ even/RB in/IN the/DT embryo/NN ;/: and/CC if/IN this/DT be/VB so/RB ,/, we/PRP could/MD understand/VB how/WRB it/PRP is/VBZ that/IN certain/JJ species/NN ,/, whilst/NN young/JJ ,/, habitually/RB fall/NN over/IN and/CC rest/NN on/IN the/DT left/VBN side/NN ,/, and/CC other/JJ species/NN on/IN the/DT right/NN side/NN ./. Malm/NNP adds/VBZ ,/, in/IN confirmation/NN of/IN the/DT above/IN view/NN ,/, that/IN the/DT adult/NN Trachypterus/NNP arcticus/JJ ,/, which/WDT is/VBZ not/RB a/DT member/NN of/IN the/DT Pleuronectidae/NNP ,/, rests/VBZ on/IN its/PRP$ left/VBN side/NN at/IN the/DT bottom/NN ,/, and/CC swims/VBZ diagonally/RB through/IN the/DT water/NN ;/: and/CC in/IN this/DT fish/NN ,/, the/DT two/CD sides/NNS of/IN the/DT head/NN are/VBP said/VBD to/TO be/VB somewhat/RB dissimilar/JJ ./. Our/PRP$ great/JJ authority/NN on/IN fishes/NNS ,/, Dr/NNP ./. Gunther/NNP ,/, concludes/VBZ his/PRP$ abstract/JJ of/IN Malm's/NNP paper/NN ,/, by/IN remarking/VBG that/IN "/" the/DT author/NN gives/VBZ a/DT very/RB simple/JJ explanation/NN of/IN the/DT abnormal/JJ condition/NN of/IN the/DT pleuronectoids/NNS ./. "/" We/PRP thus/RB see/VB that/IN the/DT first/JJ stages/NNS of/IN the/DT transit/NN of/IN the/DT eye/NN from/IN one/CD side/NN of/IN the/DT head/NN to/TO the/DT other/JJ ,/, which/WDT Mr/NNP ./. Mivart/NNP considers/VBZ would/MD be/VB injurious/JJ ,/, may/MD be/VB attributed/VBD to/TO the/DT habit/NN ,/, no/DT doubt/NN beneficial/JJ to/TO the/DT individual/JJ and/CC to/TO the/DT species/NN ,/, of/IN endeavouring/VBG to/TO look/VB upwards/RB with/IN both/DT eyes/NNS ,/, whilst/NN resting/VBG on/IN one/CD side/NN at/IN the/DT bottom/NN ./. We/PRP may/MD also/RB attribute/VBP to/TO the/DT inherited/VBN effects/NNS of/IN use/NN the/DT fact/NN of/IN the/DT mouth/NN in/IN several/JJ kinds/NNS of/IN flat/JJ fish/NN being/VBG bent/VBD towards/IN the/DT lower/JJR surface/NN ,/, with/IN the/DT jaw/NN bones/NNS stronger/JJR and/CC more/JJR effective/JJ on/IN this/DT ,/, the/DT eyeless/JJ side/NN of/IN the/DT head/NN ,/, than/IN on/IN the/DT other/JJ ,/, for/IN the/DT sake/NN ,/, as/IN Dr/NNP ./. Traquair/NNP supposes/VBZ ,/, of/IN feeding/VBG with/IN ease/VB on/IN the/DT ground/NN ./. Disuse/NNP ,/, on/IN the/DT other/JJ hand/NN ,/, will/MD account/NN for/IN the/DT less/JJR developed/VBN condition/NN of/IN the/DT whole/JJ inferior/JJ half/NN of/IN the/DT body/NN ,/, including/VBG the/DT lateral/JJ fins/NNS ;/: though/IN Yarrel/NNP thinks/VBZ that/IN the/DT reduced/VBN size/NN of/IN these/DT fins/NNS is/VBZ advantageous/JJ to/TO the/DT fish/NN ,/, as/IN "/" there/EX is/VBZ so/RB much/JJ less/JJR room/NN for/IN their/PRP$ action/NN ,/, than/IN with/IN the/DT larger/JJR fins/NNS above/IN ./. "/" Perhaps/RB the/DT lesser/JJR number/NN of/IN teeth/NNS in/IN the/DT proportion/NN of/IN four/CD to/TO seven/CD in/IN the/DT upper/JJ halves/NNS of/IN the/DT two/CD jaws/NNS of/IN the/DT plaice/NN ,/, to/TO twenty/CD five/CD to/TO thirty/CD in/IN the/DT lower/JJR halves/NNS ,/, may/MD likewise/RB be/VB accounted/VBD for/IN by/IN disuse/NN ./. From/IN the/DT colourless/JJ state/NN of/IN the/DT ventral/JJ surface/NN of/IN most/RBS fishes/NNS and/CC of/IN many/JJ other/JJ animals/NNS ,/, we/PRP may/MD reasonably/RB suppose/VBP that/IN the/DT absence/NN of/IN colour/NN in/IN flat/JJ fish/NN on/IN the/DT side/NN ,/, whether/IN it/PRP be/VB the/DT right/NN or/CC left/VBN ,/, which/WDT is/VBZ undermost/JJ ,/, is/VBZ due/JJ to/TO the/DT exclusion/NN of/IN light/NN ./. But/CC it/PRP cannot/MD be/VB supposed/VBN that/IN the/DT peculiar/JJ speckled/JJ appearance/NN of/IN the/DT upper/JJ side/NN of/IN the/DT sole/JJ ,/, so/RB like/IN the/DT sandy/JJ bed/NN of/IN the/DT sea/NN ,/, or/CC the/DT power/NN in/IN some/DT species/NN ,/, as/IN recently/RB shown/VBN by/IN Pouchet/NNP ,/, of/IN changing/VBG their/PRP$ colour/NN in/IN accordance/NN with/IN the/DT surrounding/VBG surface/NN ,/, or/CC the/DT presence/NN of/IN bony/JJ tubercles/NNS on/IN the/DT upper/JJ side/NN of/IN the/DT turbot/NN ,/, are/VBP due/JJ to/TO the/DT action/NN of/IN the/DT light/NN ./. Here/RB natural/JJ selection/NN has/VBZ probably/RB come/VB into/IN play/VB ,/, as/IN well/RB as/IN in/IN adapting/VBG the/DT general/JJ shape/NN of/IN the/DT body/NN of/IN these/DT fishes/NNS ,/, and/CC many/JJ other/JJ peculiarities/NNS ,/, to/TO their/PRP$ habits/NNS of/IN life/NN ./. We/PRP should/MD keep/VB in/IN mind/NN ,/, as/IN I/PRP have/VBP before/IN insisted/VBD ,/, that/IN the/DT inherited/VBN effects/NNS of/IN the/DT increased/VBN use/NN of/IN parts/NNS ,/, and/CC perhaps/RB of/IN their/PRP$ disuse/NN ,/, will/MD be/VB strengthened/VBN by/IN natural/JJ selection/NN ./. For/IN all/DT spontaneous/JJ variations/NNS in/IN the/DT right/NN direction/NN will/MD thus/RB be/VB preserved/VBN ;/: as/IN will/MD those/DT individuals/NNS which/WDT inherit/VB in/IN the/DT highest/JJS degree/NN the/DT effects/NNS of/IN the/DT increased/VBN and/CC beneficial/JJ use/NN of/IN any/DT part/NN ./. How/WRB much/JJ to/TO attribute/VB in/IN each/DT particular/JJ case/NN to/TO the/DT effects/NNS of/IN use/NN ,/, and/CC how/WRB much/JJ to/TO natural/JJ selection/NN ,/, it/PRP seems/VBZ impossible/JJ to/TO decide/VB ./. I/PRP may/MD give/VB another/DT instance/NN of/IN a/DT structure/NN which/WDT apparently/RB owes/VBZ its/PRP$ origin/NN exclusively/RB to/TO use/NN or/CC habit/NN ./. The/DT extremity/NN of/IN the/DT tail/NN in/IN some/DT American/NNP monkeys/NNS has/VBZ been/VBN converted/VBN into/IN a/DT wonderfully/RB perfect/JJ prehensile/NN organ/NN ,/, and/CC serves/VBZ as/IN a/DT fifth/JJ hand/NN ./. A/DT reviewer/NN who/WP agrees/VBZ with/IN Mr/NNP ./. Mivart/NNP in/IN every/DT detail/NN ,/, remarks/NNS on/IN this/DT structure/NN :/: "/" It/PRP is/VBZ impossible/JJ to/TO believe/VB that/IN in/IN any/DT number/NN of/IN ages/NNS the/DT first/JJ slight/JJ incipient/JJ tendency/NN to/TO grasp/VB could/MD preserve/VB the/DT lives/NNS of/IN the/DT individuals/NNS possessing/VBG it/PRP ,/, or/CC favour/NN their/PRP$ chance/NN of/IN having/VBG and/CC of/IN rearing/VBG offspring/NN ./. "/" But/CC there/EX is/VBZ no/DT necessity/NN for/IN any/DT such/JJ belief/NN ./. Habit/NNP ,/, and/CC this/DT almost/RB implies/VBZ that/IN some/DT benefit/NN great/JJ or/CC small/JJ is/VBZ thus/RB derived/VBN ,/, would/MD in/IN all/DT probability/NN suffice/VB for/IN the/DT work/NN ./. Brehm/NNP saw/VBD the/DT young/JJ of/IN an/DT African/JJ monkey/NN (/( Cercopithecus/NNP )/SYM clinging/VBG to/TO the/DT under/IN surface/NN of/IN their/PRP$ mother/NN by/IN their/PRP$ hands/NNS ,/, and/CC at/IN the/DT same/JJ time/NN they/PRP hooked/VBN their/PRP$ little/JJ tails/NNS round/NN that/IN of/IN their/PRP$ mother/NN ./. Professor/NNP Henslow/NNP kept/VBD in/IN confinement/NN some/DT harvest/NN mice/NNS (/( Mus/NNP messorius/JJ )/SYM which/WDT do/VBP not/RB possess/VBP a/DT structurally/RB prehensile/NN tail/NN ;/: but/CC he/PRP frequently/RB observed/VBN that/IN they/PRP curled/VBD their/PRP$ tails/NNS round/NN the/DT branches/NNS of/IN a/DT bush/NN placed/VBN in/IN the/DT cage/NN ,/, and/CC thus/RB aided/VBN themselves/PRP in/IN climbing/VBG ./. I/PRP have/VBP received/VBD an/DT analogous/JJ account/NN from/IN Dr/NNP ./. Gunther/NNP ,/, who/WP has/VBZ seen/VBN a/DT mouse/NN thus/RB suspend/VB itself/PRP ./. If/IN the/DT harvest/NN mouse/NN had/VBD been/VBN more/JJR strictly/RB arboreal/JJ ,/, it/PRP would/MD perhaps/RB have/VBP had/VBD its/PRP$ tail/NN rendered/VBN structurally/RB prehensile/NN ,/, as/IN is/VBZ the/DT case/NN with/IN some/DT members/NNS of/IN the/DT same/JJ order/NN ./. Why/WRB Cereopithecus/NNP ,/, considering/VBG its/PRP$ habits/NNS whilst/NN young/JJ ,/, has/VBZ not/RB become/VB thus/RB provided/VBN ,/, it/PRP would/MD be/VB difficult/JJ to/TO say/VB ./. It/PRP is/VBZ ,/, however/RB ,/, possible/JJ that/IN the/DT long/JJ tail/NN of/IN this/DT monkey/NN may/MD be/VB of/IN more/JJR service/NN to/TO it/PRP as/IN a/DT balancing/NN organ/NN in/IN making/VBG its/PRP$ prodigious/JJ leaps/NNS ,/, than/IN as/IN a/DT prehensile/NN organ/NN ./. The/DT mammary/JJ glands/NNS are/VBP common/JJ to/TO the/DT whole/JJ class/NN of/IN mammals/NNS ,/, and/CC are/VBP indispensable/JJ for/IN their/PRP$ existence/NN ;/: they/PRP must/MD ,/, therefore/RB ,/, have/VBP been/VBN developed/VBN at/IN an/DT extremely/RB remote/JJ period/NN ,/, and/CC we/PRP can/MD know/VB nothing/NN positively/RB about/IN their/PRP$ manner/NN of/IN development/NN ./. Mr/NNP ./. Mivart/NNP asks/VBZ :/: "/" Is/VBZ it/PRP conceivable/JJ that/IN the/DT young/JJ of/IN any/DT animal/NN was/VBD ever/RB saved/VBN from/IN destruction/NN by/IN accidentally/RB sucking/VBG a/DT drop/NN of/IN scarcely/RB nutritious/JJ fluid/NN from/IN an/DT accidentally/RB hypertrophied/VBN cutaneous/JJ gland/NN of/IN its/PRP$ mother/NN ?/. And/CC even/RB if/IN one/CD was/VBD so/RB ,/, what/WP chance/NN was/VBD there/EX of/IN the/DT perpetuation/NN of/IN such/JJ a/DT variation/NN ?/. "/" But/CC the/DT case/NN is/VBZ not/RB here/RB put/VB fairly/RB ./. It/PRP is/VBZ admitted/VBN by/IN most/RBS evolutionists/NNS that/IN mammals/NNS are/VBP descended/VBD from/IN a/DT marsupial/JJ form/NN ;/: and/CC if/IN so/RB ,/, the/DT mammary/JJ glands/NNS will/MD have/VB been/VBN at/IN first/JJ developed/VBN within/IN the/DT marsupial/JJ sack/NN ./. In/IN the/DT case/NN of/IN the/DT fish/NN (/( Hippocampus/NNP )/SYM the/DT eggs/NNS are/VBP hatched/VBN ,/, and/CC the/DT young/JJ are/VBP reared/VBD for/IN a/DT time/NN ,/, within/IN a/DT sack/NN of/IN this/DT nature/NN ;/: and/CC an/DT American/NNP naturalist/NN ,/, Mr/NNP ./. Lockwood/NNP ,/, believes/VBZ from/IN what/WP he/PRP has/VBZ seen/VBN of/IN the/DT development/NN of/IN the/DT young/JJ ,/, that/IN they/PRP are/VBP nourished/VBN by/IN a/DT secretion/NN from/IN the/DT cutaneous/JJ glands/NNS of/IN the/DT sack/NN ./. Now/RB with/IN the/DT early/JJ progenitors/NNS of/IN mammals/NNS ,/, almost/RB before/IN they/PRP deserved/VBD to/TO be/VB thus/RB designated/VBN ,/, is/VBZ it/PRP not/RB at/IN least/JJS possible/JJ that/IN the/DT young/JJ might/MD have/VB been/VBN similarly/RB nourished/VBN ?/. And/CC in/IN this/DT case/NN ,/, the/DT individuals/NNS which/WDT secreted/VBN a/DT fluid/NN ,/, in/IN some/DT degree/NN or/CC manner/NN the/DT most/RBS nutritious/JJ ,/, so/RB as/IN to/TO partake/VB of/IN the/DT nature/NN of/IN milk/NN ,/, would/MD in/IN the/DT long/JJ run/VB have/VBP reared/VBD a/DT larger/JJR number/NN of/IN well/RB nourished/VBN offspring/NN ,/, than/IN would/MD the/DT individuals/NNS which/WDT secreted/VBN a/DT poorer/JJR fluid/NN ;/: and/CC thus/RB the/DT cutaneous/JJ glands/NNS ,/, which/WDT are/VBP the/DT homologues/NNS of/IN the/DT mammary/JJ glands/NNS ,/, would/MD have/VB been/VBN improved/VBN or/CC rendered/VBN more/JJR effective/JJ ./. It/PRP accords/NNS with/IN the/DT widely/RB extended/VBN principle/NN of/IN specialisation/NN ,/, that/IN the/DT glands/NNS over/IN a/DT certain/JJ space/NN of/IN the/DT sack/NN should/MD have/VB become/VB more/JJR highly/RB developed/VBN than/IN the/DT remainder/NN ;/: and/CC they/PRP would/MD then/RB have/VBP formed/VBN a/DT breast/NN ,/, but/CC at/IN first/JJ without/IN a/DT nipple/NN as/IN we/PRP see/VB in/IN the/DT Ornithorhynchus/NNP ,/, at/IN the/DT base/NN of/IN the/DT mammalian/JJ series/NN ./. Through/IN what/WP agency/NN the/DT glands/NNS over/IN a/DT certain/JJ space/NN became/VBD more/JJR highly/RB specialised/VBN than/IN the/DT others/NNS ,/, I/PRP will/MD not/RB pretend/VB to/TO decide/VB ,/, whether/IN in/IN part/NN through/IN compensation/NN of/IN growth/NN ,/, the/DT effects/NNS of/IN use/NN ,/, or/CC of/IN natural/JJ selection/NN ./. The/DT development/NN of/IN the/DT mammary/JJ glands/NNS would/MD have/VB been/VBN of/IN no/DT service/NN ,/, and/CC could/MD not/RB have/VBP been/VBN effected/VBN through/IN natural/JJ selection/NN ,/, unless/IN the/DT young/JJ at/IN the/DT same/JJ time/NN were/VBD able/JJ to/TO partake/VB of/IN the/DT secretion/NN ./. There/EX is/VBZ no/DT greater/JJR difficulty/NN in/IN understanding/NN how/WRB young/JJ mammals/NNS have/VBP instinctively/RB learnt/NN to/TO suck/VB the/DT breast/NN ,/, than/IN in/IN understanding/NN how/WRB unhatched/JJ chickens/NNS have/VBP learnt/NN to/TO break/VB the/DT egg/NN shell/NN by/IN tapping/VBG against/IN it/PRP with/IN their/PRP$ specially/RB adapted/VBN beaks/NNS ;/: or/CC how/WRB a/DT few/JJ hours/NNS after/IN leaving/VBG the/DT shell/NN they/PRP have/VBP learnt/NN to/TO pick/VB up/IN grains/NNS of/IN food/NN ./. In/IN such/JJ cases/NNS the/DT most/RBS probable/JJ solution/NN seems/VBZ to/TO be/VB ,/, that/IN the/DT habit/NN was/VBD at/IN first/JJ acquired/VBN by/IN practice/NN at/IN a/DT more/JJR advanced/VBD age/NN ,/, and/CC afterwards/RB transmitted/VBN to/TO the/DT offspring/NN at/IN an/DT earlier/RBR age/NN ./. But/CC the/DT young/JJ kangaroo/NN is/VBZ said/VBD not/RB to/TO suck/VB ,/, only/RB to/TO cling/VB to/TO the/DT nipple/NN of/IN its/PRP$ mother/NN ,/, who/WP has/VBZ the/DT power/NN of/IN injecting/VBG milk/NN into/IN the/DT mouth/NN of/IN her/PRP$ helpless/JJ ,/, half/NN formed/VBN offspring/NN ./. On/IN this/DT head/NN ,/, Mr/NNP ./. Mivart/NNP remarks/NNS :/: "/" Did/VBD no/DT special/JJ provision/NN exist/VB ,/, the/DT young/JJ one/CD must/MD infallibly/RB be/VB choked/VBD by/IN the/DT intrusion/NN of/IN the/DT milk/NN into/IN the/DT windpipe/NN ./. But/CC there/EX is/VBZ a/DT special/JJ provision/NN ./. The/DT larynx/NN is/VBZ so/RB elongated/VBN that/IN it/PRP rises/VBZ up/IN into/IN the/DT posterior/JJ end/NN of/IN the/DT nasal/JJ passage/NN ,/, and/CC is/VBZ thus/RB enabled/VBD to/TO give/VB free/JJ entrance/NN to/TO the/DT air/NN for/IN the/DT lungs/NNS ,/, while/IN the/DT milk/NN passes/VBZ harmlessly/RB on/IN each/DT side/NN of/IN this/DT elongated/VBN larynx/NN ,/, and/CC so/RB safely/RB attains/VBZ the/DT gullet/NN behind/IN it/PRP ./. "/" Mr/NNP ./. Mivart/NNP then/RB asks/VBZ how/WRB did/VBD natural/JJ selection/NN remove/VB in/IN the/DT adult/NN kangaroo/NN (/( and/CC in/IN most/RBS other/JJ mammals/NNS ,/, on/IN the/DT assumption/NN that/IN they/PRP are/VBP descended/VBD from/IN a/DT marsupial/JJ form/NN )/SYM ,/, "/" this/DT at/IN least/JJS perfectly/RB innocent/JJ and/CC harmless/JJ structure/NN ?/. "/" It/PRP may/MD be/VB suggested/VBD in/IN answer/NN that/IN the/DT voice/NN ,/, which/WDT is/VBZ certainly/RB of/IN high/JJ importance/NN to/TO many/JJ animals/NNS ,/, could/MD hardly/RB have/VBP been/VBN used/VBN with/IN full/JJ force/NN as/IN long/JJ as/IN the/DT larynx/NN entered/VBD the/DT nasal/JJ passage/NN ;/: and/CC Professor/NNP Flower/NNP has/VBZ suggested/VBN to/TO me/PRP that/IN this/DT structure/NN would/MD have/VB greatly/RB interfered/VBD with/IN an/DT animal/NN swallowing/VBG solid/JJ food/NN ./. We/PRP will/MD now/RB turn/VB for/IN a/DT short/JJ space/NN to/TO the/DT lower/JJR divisions/NNS of/IN the/DT animal/NN kingdom/NN ./. The/DT Echinodermata/NNP (/( star/NN fishes/NNS ,/, sea/NN urchins/NNS ,/, &c/NN ./. )/SYM are/VBP furnished/VBN with/IN remarkable/JJ organs/NNS ,/, called/VBN pedicellariae/NN ,/, which/WDT consist/VB ,/, when/WRB well/RB developed/VBN ,/, of/IN a/DT tridactyle/NN forceps/NNS that/IN is/VBZ ,/, of/IN one/CD formed/VBN of/IN three/CD serrated/VBN arms/NNS ,/, neatly/RB fitting/JJ together/RB and/CC placed/VBN on/IN the/DT summit/NN of/IN a/DT flexible/JJ stem/VB ,/, moved/VBD by/IN muscles/NNS ./. These/DT forceps/NNS can/MD firmly/RB seize/VB hold/VB of/IN any/DT object/NN ;/: and/CC Alexander/NNP Agassiz/NNP has/VBZ seen/VBN an/DT Echinus/NNP or/CC sea/NN urchin/NN rapidly/RB passing/VBG particles/NNS of/IN excrement/NN from/IN forceps/NNS to/TO forceps/NNS down/RB certain/JJ lines/NNS of/IN its/PRP$ body/NN ,/, in/IN order/NN that/IN its/PRP$ shell/NN should/MD not/RB be/VB fouled/VBD ./. But/CC there/EX is/VBZ no/DT doubt/NN that/IN besides/IN removing/VBG dirt/NN of/IN all/DT kinds/NNS ,/, they/PRP subserve/NN other/JJ functions/NNS ;/: and/CC one/CD of/IN these/DT apparently/RB is/VBZ defence/NN ./. With/IN respect/NN to/TO these/DT organs/NNS ,/, Mr/NNP ./. Mivart/NNP ,/, as/IN on/IN so/RB many/JJ previous/JJ occasions/NNS ,/, asks/VBZ :/: "/" What/WP would/MD be/VB the/DT utility/NN of/IN the/DT first/JJ rudimentary/JJ beginnings/NNS of/IN such/JJ structures/NNS ,/, and/CC how/WRB could/MD such/JJ incipient/JJ buddings/NNS have/VBP ever/RB preserved/VBN the/DT life/NN of/IN a/DT single/JJ Echinus/NNP ?/. "/" He/PRP adds/VBZ ,/, "/" Not/RB even/RB the/DT sudden/JJ development/NN of/IN the/DT snapping/VBG action/NN could/MD have/VB been/VBN beneficial/JJ without/IN the/DT freely/RB moveable/JJ stalk/VBP ,/, nor/CC could/MD the/DT latter/NN have/VBP been/VBN efficient/JJ without/IN the/DT snapping/VBG jaws/NNS ,/, yet/RB no/DT minute/NN merely/RB indefinite/JJ variations/NNS could/MD simultaneously/RB evolve/VB these/DT complex/JJ co/NN ordinations/NNS of/IN structure/NN ;/: to/TO deny/VB this/DT seems/VBZ to/TO do/VB no/DT less/JJR than/IN to/TO affirm/VB a/DT startling/JJ paradox/NN ./. "/" Paradoxical/JJ as/IN this/DT may/MD appear/VB to/TO Mr/NNP ./. Mivart/NNP ,/, tridactyle/NN forcepses/NNS ,/, immovably/RB fixed/VBN at/IN the/DT base/NN ,/, but/CC capable/JJ of/IN a/DT snapping/VBG action/NN ,/, certainly/RB exist/VB on/IN some/DT starfishes/NNS ;/: and/CC this/DT is/VBZ intelligible/JJ if/IN they/PRP serve/VB ,/, at/IN least/JJS in/IN part/NN ,/, as/IN a/DT means/VBZ of/IN defence/NN ./. Mr/NNP ./. Agassiz/NNP ,/, to/TO whose/WP$ great/JJ kindness/NN I/PRP am/VBP indebted/JJ for/IN much/JJ information/NN on/IN the/DT subject/NN ,/, informs/VBZ me/PRP that/IN there/EX are/VBP other/JJ star/NN fishes/NNS ,/, in/IN which/WDT one/CD of/IN the/DT three/CD arms/NNS of/IN the/DT forceps/NNS is/VBZ reduced/VBN to/TO a/DT support/NN for/IN the/DT other/JJ two/CD ;/: and/CC again/RB ,/, other/JJ genera/NN in/IN which/WDT the/DT third/JJ arm/NN is/VBZ completely/RB lost/VBD ./. In/IN Echinoneus/NNP ,/, the/DT shell/NN is/VBZ described/VBN by/IN M/NNP ./. Perrier/NNP as/IN bearing/VBG two/CD kinds/NNS of/IN pedicellariae/NN ,/, one/CD resembling/VBG those/DT of/IN Echinus/NNP ,/, and/CC the/DT other/JJ those/DT of/IN Spatangus/NNP ;/: and/CC such/JJ cases/NNS are/VBP always/RB interesting/JJ as/IN affording/VBG the/DT means/VBZ of/IN apparently/RB sudden/JJ transitions/NNS ,/, through/IN the/DT abortion/NN of/IN one/CD of/IN the/DT two/CD states/NNS of/IN an/DT organ/NN ./. With/IN respect/NN to/TO the/DT steps/NNS by/IN which/WDT these/DT curious/JJ organs/NNS have/VBP been/VBN evolved/VBN ,/, Mr/NNP ./. Agassiz/NNP infers/NNS from/IN his/PRP$ own/JJ researches/VBZ and/CC those/DT of/IN Muller/NNP ,/, that/IN both/DT in/IN star/NN fishes/NNS and/CC sea/NN urchins/NNS the/DT pedicellariae/NN must/MD undoubtedly/RB be/VB looked/VBD at/IN as/IN modified/VBN spines/NNS ./. This/DT may/MD be/VB inferred/VBD from/IN their/PRP$ manner/NN of/IN development/NN in/IN the/DT individual/JJ ,/, as/IN well/RB as/IN from/IN a/DT long/JJ and/CC perfect/JJ series/NN of/IN gradations/NNS in/IN different/JJ species/NN and/CC genera/NN ,/, from/IN simple/JJ granules/NNS to/TO ordinary/JJ spines/NNS ,/, to/TO perfect/JJ tridactyle/NN pedicellariae/NN ./. The/DT gradations/NNS extend/VB even/RB to/TO the/DT manner/NN in/IN which/WDT ordinary/JJ spines/NNS and/CC pedicellariae/NN with/IN their/PRP$ supporting/VBG calcareous/JJ rods/NNS are/VBP articulated/VBN to/TO the/DT shell/NN ./. In/IN certain/JJ genera/NN of/IN star/NN fishes/NNS ,/, "/" the/DT very/RB combinations/NNS needed/VBN to/TO show/NN that/IN the/DT pedicellariae/NN are/VBP only/RB modified/VBN branching/VBG spines/NNS "/" may/MD be/VB found/VBD ./. Thus/RB we/PRP have/VBP fixed/VBN spines/NNS ,/, with/IN three/CD equidistant/JJ ,/, serrated/VBN ,/, moveable/JJ branches/NNS ,/, articulated/VBN to/TO near/IN their/PRP$ bases/NNS ;/: and/CC higher/JJR up/IN ,/, on/IN the/DT same/JJ spine/NN ,/, three/CD other/JJ moveable/JJ branches/NNS ./. Now/RB when/WRB the/DT latter/NN arise/VB from/IN the/DT summit/NN of/IN a/DT spine/NN they/PRP form/NN in/IN fact/NN a/DT rude/JJ tridactyle/NN pedicellaria/NN ,/, and/CC such/JJ may/MD be/VB seen/VBN on/IN the/DT same/JJ spine/NN together/RB with/IN the/DT three/CD lower/JJR branches/NNS ./. In/IN this/DT case/NN the/DT identity/NN in/IN nature/NN between/IN the/DT arms/NNS of/IN the/DT pedicellariae/NN and/CC the/DT moveable/JJ branches/NNS of/IN a/DT spine/NN ,/, is/VBZ unmistakable/JJ ./. It/PRP is/VBZ generally/RB admitted/VBD that/IN the/DT ordinary/JJ spines/NNS serve/VB as/IN a/DT protection/NN ;/: and/CC if/IN so/RB ,/, there/EX can/MD be/VB no/DT reason/NN to/TO doubt/NN that/IN those/DT furnished/VBN with/IN serrated/VBN and/CC moveable/JJ branches/NNS likewise/RB serve/VB for/IN the/DT same/JJ purpose/NN ;/: and/CC they/PRP would/MD thus/RB serve/VB still/RB more/JJR effectively/RB as/IN soon/RB as/IN by/IN meeting/NN together/RB they/PRP acted/VBD as/IN a/DT prehensile/NN or/CC snapping/VBG apparatus/NN ./. Thus/RB every/DT gradation/NN ,/, from/IN an/DT ordinary/JJ fixed/VBN spine/NN to/TO a/DT fixed/VBN pedicellaria/NN ,/, would/MD be/VB of/IN service/NN ./. In/IN certain/JJ genera/NN of/IN star/NN fishes/NNS these/DT organs/NNS ,/, instead/RB of/IN being/VBG fixed/VBN or/CC borne/VBN on/IN an/DT immoveable/JJ support/NN ,/, are/VBP placed/VBN on/IN the/DT summit/NN of/IN a/DT flexible/JJ and/CC muscular/JJ ,/, though/IN short/JJ ,/, stem/VB ;/: and/CC in/IN this/DT case/NN they/PRP probably/RB subserve/NN some/DT additional/JJ function/NN besides/IN defence/NN ./. In/IN the/DT sea/NN urchins/NNS the/DT steps/NNS can/MD be/VB followed/VBD by/IN which/WDT a/DT fixed/VBN spine/NN becomes/VBZ articulated/VBN to/TO the/DT shell/NN ,/, and/CC is/VBZ thus/RB rendered/VBN moveable/JJ ./. I/PRP wish/VBP I/PRP had/VBD space/NN here/RB to/TO give/VB a/DT fuller/JJR abstract/JJ of/IN Mr/NNP ./. Agassiz's/NNP interesting/JJ observations/NNS on/IN the/DT development/NN of/IN the/DT pedicellariae/NN ./. All/DT possible/JJ gradations/NNS ,/, as/IN he/PRP adds/VBZ ,/, may/MD likewise/RB be/VB found/VBD between/IN the/DT pedicellariae/NN of/IN the/DT star/NN fishes/NNS and/CC the/DT hooks/NNS of/IN the/DT ophiurians/NNS ,/, another/DT group/NN of/IN Echinodermata/NNP ;/: and/CC again/RB between/IN the/DT pedicellariae/NN of/IN sea/NN urchins/NNS and/CC the/DT anchors/NNS of/IN the/DT Holothuriae/NNP ,/, also/RB belonging/VBG to/TO the/DT same/JJ great/JJ class/NN ./. Certain/JJ compound/NN animals/NNS ,/, or/CC zoophytes/NNS as/IN they/PRP have/VBP been/VBN termed/VBD ,/, namely/RB the/DT Polyzoa/NNP ,/, are/VBP provided/VBN with/IN curious/JJ organs/NNS called/VBN avicularia/NN ./. These/DT differ/VBP much/JJ in/IN structure/NN in/IN the/DT different/JJ species/NN ./. In/IN their/PRP$ most/RBS perfect/JJ condition/NN ,/, they/PRP curiously/RB resemble/VB the/DT head/NN and/CC beak/NN of/IN a/DT vulture/NN in/IN miniature/JJ ,/, seated/VBN on/IN a/DT neck/NN and/CC capable/JJ of/IN movement/NN ,/, as/IN is/VBZ likewise/RB the/DT lower/JJR jaw/NN or/CC mandible/JJ ./. In/IN one/CD species/NN observed/VBN by/IN me/PRP all/DT the/DT avicularia/NN on/IN the/DT same/JJ branch/NN often/RB moved/VBD simultaneously/RB backwards/RB and/CC forwards/RB ,/, with/IN the/DT lower/JJR jaw/NN widely/RB open/JJ ,/, through/IN an/DT angle/NN of/IN about/IN 90/CD degrees/NNS ,/, in/IN the/DT course/NN of/IN five/CD seconds/NNS ;/: and/CC their/PRP$ movement/NN caused/VBN the/DT whole/JJ polyzoary/JJ to/TO tremble/VB ./. When/WRB the/DT jaws/NNS are/VBP touched/VBD with/IN a/DT needle/NN they/PRP seize/VB it/PRP so/RB firmly/RB that/IN the/DT branch/NN can/MD thus/RB be/VB shaken/VBN ./. Mr/NNP ./. Mivart/NNP adduces/NNS this/DT case/NN ,/, chiefly/RB on/IN account/NN of/IN the/DT supposed/VBN difficulty/NN of/IN organs/NNS ,/, namely/RB the/DT avicularia/NN of/IN the/DT Polyzoa/NNP and/CC the/DT pedicellariae/NN of/IN the/DT Echinodermata/NNP ,/, which/WDT he/PRP considers/VBZ as/IN "/" essentially/RB similar/JJ ,/, "/" having/VBG been/VBN developed/VBN through/IN natural/JJ selection/NN in/IN widely/RB distinct/JJ divisions/NNS of/IN the/DT animal/NN kingdom/NN ./. But/CC ,/, as/IN far/RB as/IN structure/NN is/VBZ concerned/VBN ,/, I/PRP can/MD see/VB no/DT similarity/NN between/IN tridactyle/NN pedicellariae/NN and/CC avicularia/NN ./. The/DT latter/NN resemble/VB somewhat/RB more/JJR closely/RB the/DT chelae/NN or/CC pincers/NNS of/IN crustaceans/NNS ;/: and/CC Mr/NNP ./. Mivart/NNP might/MD have/VB adduced/VBN with/IN equal/JJ appropriateness/NN this/DT resemblance/NN as/IN a/DT special/JJ difficulty/NN ;/: or/CC even/RB their/PRP$ resemblance/NN to/TO the/DT head/NN and/CC beak/NN of/IN a/DT bird/NN ./. The/DT avicularia/NN are/VBP believed/VBD by/IN Mr/NNP ./. Busk/NNP ,/, Dr/NNP ./. Smitt/NNP ,/, and/CC Dr/NNP ./. Nitsche/NNP naturalists/NNS who/WP have/VBP carefully/RB studied/VBN this/DT group/NN to/TO be/VB homologous/RB with/IN the/DT zooids/NNS and/CC their/PRP$ cells/NNS which/WDT compose/VB the/DT zoophyte/NN ;/: the/DT moveable/JJ lip/NN or/CC lid/NN of/IN the/DT cell/NN corresponding/JJ with/IN the/DT lower/JJR and/CC moveable/JJ mandible/JJ of/IN the/DT avicularium/NN ./. Mr/NNP ./. Busk/NNP ,/, however/RB ,/, does/VBZ not/RB know/VB of/IN any/DT gradations/NNS now/RB existing/VBG between/IN a/DT zooid/JJ and/CC an/DT avicularium/NN ./. It/PRP is/VBZ therefore/RB impossible/JJ to/TO conjecture/NN by/IN what/WP serviceable/JJ gradations/NNS the/DT one/CD could/MD have/VB been/VBN converted/VBN into/IN the/DT other/JJ :/: but/CC it/PRP by/IN no/DT means/VBZ follows/VBZ from/IN this/DT that/IN such/JJ gradations/NNS have/VBP not/RB existed/VBD ./. As/IN the/DT chelae/NN of/IN crustaceans/NNS resemble/VB in/IN some/DT degree/NN the/DT avicularia/NN of/IN Polyzoa/NNP ,/, both/DT serving/VBG as/IN pincers/NNS ,/, it/PRP may/MD be/VB worth/JJ while/IN to/TO show/NN that/IN with/IN the/DT former/JJ a/DT long/JJ series/NN of/IN serviceable/JJ gradations/NNS still/RB exists/VBZ ./. In/IN the/DT first/JJ and/CC simplest/JJS stage/NN ,/, the/DT terminal/NN segment/NN of/IN a/DT limb/NN shuts/VBZ down/RB either/DT on/IN the/DT square/NN summit/NN of/IN the/DT broad/JJ penultimate/JJ segment/NN ,/, or/CC against/IN one/CD whole/JJ side/NN ;/: and/CC is/VBZ thus/RB enabled/VBD to/TO catch/VB hold/VB of/IN an/DT object/NN ;/: but/CC the/DT limb/NN still/RB serves/VBZ as/IN an/DT organ/NN of/IN locomotion/NN ./. We/PRP next/JJ find/VB one/CD corner/NN of/IN the/DT broad/JJ penultimate/JJ segment/NN slightly/RB prominent/JJ ,/, sometimes/RB furnished/VBN with/IN irregular/JJ teeth/NNS ;/: and/CC against/IN these/DT the/DT terminal/NN segment/NN shuts/VBZ down/RB ./. By/IN an/DT increase/NN in/IN the/DT size/NN of/IN this/DT projection/NN ,/, with/IN its/PRP$ shape/NN ,/, as/IN well/RB as/IN that/IN of/IN the/DT terminal/NN segment/NN ,/, slightly/RB modified/VBN and/CC improved/VBN ,/, the/DT pincers/NNS are/VBP rendered/VBN more/JJR and/CC more/JJR perfect/JJ ,/, until/IN we/PRP have/VBP at/IN last/JJ an/DT instrument/NN as/IN efficient/JJ as/IN the/DT chelae/NN of/IN a/DT lobster/NN ;/: and/CC all/DT these/DT gradations/NNS can/MD be/VB actually/RB traced/VBN ./. Besides/IN the/DT avicularia/NN ,/, the/DT Polyzoa/NNP possess/VBP curious/JJ organs/NNS called/VBN vibracula/NN ./. These/DT generally/RB consist/VB of/IN long/JJ bristles/VBZ ,/, capable/JJ of/IN movement/NN and/CC easily/RB excited/VBN ./. In/IN one/CD species/NN examined/VBD by/IN me/PRP the/DT vibracula/NN were/VBD slightly/RB curved/JJ and/CC serrated/VBN along/IN the/DT outer/JJ margin/NN ;/: and/CC all/DT of/IN them/PRP on/IN the/DT same/JJ polyzoary/JJ often/RB moved/VBD simultaneously/RB ;/: so/RB that/IN ,/, acting/VBG like/IN long/JJ oars/NNS ,/, they/PRP swept/VBD a/DT branch/NN rapidly/RB across/IN the/DT object/NN glass/NN of/IN my/PRP$ microscope/NN ./. When/WRB a/DT branch/NN was/VBD placed/VBN on/IN its/PRP$ face/NN ,/, the/DT vibracula/NN became/VBD entangled/JJ ,/, and/CC they/PRP made/VBN violent/JJ efforts/NNS to/TO free/JJ themselves/PRP ./. They/PRP are/VBP supposed/VBN to/TO serve/VB as/IN a/DT defence/NN ,/, and/CC may/MD be/VB seen/VBN ,/, as/IN Mr/NNP ./. Busk/NNP remarks/NNS ,/, "/" to/TO sweep/NN slowly/RB and/CC carefully/RB over/IN the/DT surface/NN of/IN the/DT polyzoary/JJ ,/, removing/VBG what/WP might/MD be/VB noxious/JJ to/TO the/DT delicate/JJ inhabitants/NNS of/IN the/DT cells/NNS when/WRB their/PRP$ tentacula/NN are/VBP protruded/VBD ./. "/" The/DT avicularia/NN ,/, like/IN the/DT vibracula/NN ,/, probably/RB serve/VB for/IN defence/NN ,/, but/CC they/PRP also/RB catch/VB and/CC kill/VB small/JJ living/VBG animals/NNS ,/, which/WDT it/PRP is/VBZ believed/VBN are/VBP afterwards/RB swept/VBD by/IN the/DT currents/NNS within/IN reach/VB of/IN the/DT tentacula/NN of/IN the/DT zooids/NNS ./. Some/DT species/NN are/VBP provided/VBN with/IN avicularia/NN and/CC vibracula/NN ;/: some/DT with/IN avicularia/NN alone/RB ,/, and/CC a/DT few/JJ with/IN vibracula/NN alone/RB ./. It/PRP is/VBZ not/RB easy/JJ to/TO imagine/VB two/CD objects/NNS more/JJR widely/RB different/JJ in/IN appearance/NN than/IN a/DT bristle/VBP or/CC vibraculum/NN ,/, and/CC an/DT avicularium/NN like/IN the/DT head/NN of/IN a/DT bird/NN ;/: yet/RB they/PRP are/VBP almost/RB certainly/RB homologous/RB and/CC have/VBP been/VBN developed/VBN from/IN the/DT same/JJ common/JJ source/NN ,/, namely/RB a/DT zooid/JJ with/IN its/PRP$ cell/NN ./. Hence/RB we/PRP can/MD understand/VB how/WRB it/PRP is/VBZ that/IN these/DT organs/NNS graduate/NN in/IN some/DT cases/NNS ,/, as/IN I/PRP am/VBP informed/VBN by/IN Mr/NNP ./. Busk/NNP ,/, into/IN each/DT other/JJ ./. Thus/RB with/IN the/DT avicularia/NN of/IN several/JJ species/NN of/IN Lepralia/NNP ,/, the/DT moveable/JJ mandible/JJ is/VBZ so/RB much/JJ produced/VBN and/CC is/VBZ so/RB like/IN a/DT bristle/VBP ,/, that/IN the/DT presence/NN of/IN the/DT upper/JJ or/CC fixed/VBN beak/NN alone/RB serves/VBZ to/TO determine/VB even/RB its/PRP$ avicularian/NN nature/NN ./. The/DT vibracula/NN may/MD have/VB been/VBN directly/RB developed/VBN from/IN the/DT lips/NNS of/IN the/DT cells/NNS ,/, without/IN having/VBG passed/VBN through/IN the/DT avicularian/NN stage/NN ;/: but/CC it/PRP seems/VBZ more/JJR probable/JJ that/IN they/PRP have/VBP passed/VBN through/IN this/DT stage/NN ,/, as/IN during/IN the/DT early/JJ stages/NNS of/IN the/DT transformation/NN ,/, the/DT other/JJ parts/NNS of/IN the/DT cell/NN with/IN the/DT included/VBD zooid/JJ could/MD hardly/RB have/VBP disappeared/VBD at/IN once/RB ./. In/IN many/JJ cases/NNS the/DT vibracula/NN have/VBP a/DT grooved/VBN support/NN at/IN the/DT base/NN ,/, which/WDT seems/VBZ to/TO represent/VB the/DT fixed/VBN beak/NN ;/: though/IN this/DT support/NN in/IN some/DT species/NN is/VBZ quite/RB absent/JJ ./. This/DT view/NN of/IN the/DT development/NN of/IN the/DT vibracula/NN ,/, if/IN trustworthy/JJ ,/, is/VBZ interesting/JJ ;/: for/IN supposing/VBG that/IN all/DT the/DT species/NN provided/VBN with/IN avicularia/NN had/VBD become/VB extinct/JJ ,/, no/DT one/CD with/IN the/DT most/RBS vivid/JJ imagination/NN would/MD ever/RB have/VBP thought/VBD that/IN the/DT vibracula/NN had/VBD originally/RB existed/VBD as/IN part/NN of/IN an/DT organ/NN ,/, resembling/VBG a/DT bird's/NNS head/NN or/CC an/DT irregular/JJ box/NN or/CC hood/NN ./. It/PRP is/VBZ interesting/JJ to/TO see/VB two/CD such/JJ widely/RB different/JJ organs/NNS developed/VBN from/IN a/DT common/JJ origin/NN ;/: and/CC as/IN the/DT moveable/JJ lip/NN of/IN the/DT cell/NN serves/VBZ as/IN a/DT protection/NN to/TO the/DT zooid/JJ ,/, there/EX is/VBZ no/DT difficulty/NN in/IN believing/VBG that/IN all/DT the/DT gradations/NNS ,/, by/IN which/WDT the/DT lip/NN became/VBD converted/VBN first/JJ into/IN the/DT lower/JJR mandible/JJ of/IN an/DT avicularium/NN and/CC then/RB into/IN an/DT elongated/VBN bristle/VBP ,/, likewise/RB served/VBN as/IN a/DT protection/NN in/IN different/JJ ways/NNS and/CC under/IN different/JJ circumstances/NNS ./. In/IN the/DT vegetable/NN kingdom/NN Mr/NNP ./. Mivart/NNP only/RB alludes/VBZ to/TO two/CD cases/NNS ,/, namely/RB the/DT structure/NN of/IN the/DT flowers/NNS of/IN orchids/NNS ,/, and/CC the/DT movements/NNS of/IN climbing/VBG plants/NNS ./. With/IN respect/NN to/TO the/DT former/JJ ,/, he/PRP says/VBZ ,/, "/" The/DT explanation/NN of/IN their/PRP$ origin/NN is/VBZ deemed/VBN thoroughly/RB unsatisfactory/JJ utterly/RB insufficient/JJ to/TO explain/VB the/DT incipient/JJ ,/, infinitesimal/JJ beginnings/NNS of/IN structures/NNS which/WDT are/VBP of/IN utility/NN only/RB when/WRB they/PRP are/VBP considerably/RB developed/VBN ./. "/" As/IN I/PRP have/VBP fully/RB treated/VBN this/DT subject/NN in/IN another/DT work/NN ,/, I/PRP will/MD here/RB give/VB only/RB a/DT few/JJ details/NNS on/IN one/CD alone/RB of/IN the/DT most/RBS striking/JJ peculiarities/NNS of/IN the/DT flowers/NNS of/IN orchids/NNS ,/, namely/RB their/PRP$ pollinia/NN ./. A/DT pollinium/NN when/WRB highly/RB developed/VBN consists/VBZ of/IN a/DT mass/NN of/IN pollen/NN grains/NNS ,/, affixed/VBN to/TO an/DT elastic/JJ footstalk/NN or/CC caudicle/NN ,/, and/CC this/DT to/TO a/DT little/JJ mass/NN of/IN extremely/RB viscid/JJ matter/NN ./. The/DT pollinia/NN are/VBP by/IN this/DT means/VBZ transported/VBN by/IN insects/NNS from/IN one/CD flower/NN to/TO the/DT stigma/NN of/IN another/DT ./. In/IN some/DT orchids/NNS there/EX is/VBZ no/DT caudicle/NN to/TO the/DT pollen/NN masses/NNS ,/, and/CC the/DT grains/NNS are/VBP merely/RB tied/VBN together/RB by/IN fine/JJ threads/NNS ;/: but/CC as/IN these/DT are/VBP not/RB confined/VBN to/TO orchids/NNS ,/, they/PRP need/NN not/RB here/RB be/VB considered/VBN ;/: yet/RB I/PRP may/MD mention/VB that/IN at/IN the/DT base/NN of/IN the/DT orchidaceous/JJ series/NN ,/, in/IN Cypripedium/NNP ,/, we/PRP can/MD see/VB how/WRB the/DT threads/NNS were/VBD probably/RB first/JJ developed/VBN ./. In/IN other/JJ orchids/NNS the/DT threads/NNS cohere/VB at/IN one/CD end/NN of/IN the/DT pollen/NN masses/NNS ;/: and/CC this/DT forms/NNS the/DT first/JJ or/CC nascent/JJ trace/NN of/IN a/DT caudicle/NN ./. That/DT this/DT is/VBZ the/DT origin/NN of/IN the/DT caudicle/NN ,/, even/RB when/WRB of/IN considerable/JJ length/NN and/CC highly/RB developed/VBN ,/, we/PRP have/VBP good/JJ evidence/NN in/IN the/DT aborted/JJ pollen/NN grains/NNS which/WDT can/MD sometimes/RB be/VB detected/VBN embedded/VBN within/IN the/DT central/JJ and/CC solid/JJ parts/NNS ./. With/IN respect/NN to/TO the/DT second/JJ chief/JJ peculiarity/NN ,/, namely/RB the/DT little/JJ mass/NN of/IN viscid/JJ matter/NN attached/VBN to/TO the/DT end/NN of/IN the/DT caudicle/NN ,/, a/DT long/JJ series/NN of/IN gradations/NNS can/MD be/VB specified/VBN ,/, each/DT of/IN plain/JJ service/NN to/TO the/DT plant/NN ./. In/IN most/RBS flowers/NNS belonging/VBG to/TO other/JJ orders/NNS the/DT stigma/NN secretes/NNS a/DT little/JJ viscid/JJ matter/NN ./. Now/RB in/IN certain/JJ orchids/NNS similar/JJ viscid/JJ matter/NN is/VBZ secreted/VBN ,/, but/CC in/IN much/JJ larger/JJR quantities/NNS by/IN one/CD alone/RB of/IN the/DT three/CD stigmas/NNS ;/: and/CC this/DT stigma/NN ,/, perhaps/RB in/IN consequence/NN of/IN the/DT copious/JJ secretion/NN ,/, is/VBZ rendered/VBN sterile/JJ ./. When/WRB an/DT insect/NN visits/NNS a/DT flower/NN of/IN this/DT kind/NN ,/, it/PRP rubs/NNS off/IN some/DT of/IN the/DT viscid/JJ matter/NN and/CC thus/RB at/IN the/DT same/JJ time/NN drags/VBZ away/RB some/DT of/IN the/DT pollen/NN grains/NNS ./. From/IN this/DT simple/JJ condition/NN ,/, which/WDT differs/VBZ but/CC little/JJ from/IN that/IN of/IN a/DT multitude/NN of/IN common/JJ flowers/NNS ,/, there/EX are/VBP endless/JJ gradations/NNS ,/, to/TO species/NN in/IN which/WDT the/DT pollen/NN mass/NN terminates/VBZ in/IN a/DT very/RB short/JJ ,/, free/JJ caudicle/NN ,/, to/TO others/NNS in/IN which/WDT the/DT caudicle/NN becomes/VBZ firmly/RB attached/VBN to/TO the/DT viscid/JJ matter/NN ,/, with/IN the/DT sterile/JJ stigma/NN itself/PRP much/JJ modified/VBN ./. In/IN this/DT latter/NN case/NN we/PRP have/VBP a/DT pollinium/NN in/IN its/PRP$ most/RBS highly/RB developed/VBN and/CC perfect/JJ condition/NN ./. He/PRP who/WP will/MD carefully/RB examine/VB the/DT flowers/NNS of/IN orchids/NNS for/IN himself/PRP will/MD not/RB deny/VB the/DT existence/NN of/IN the/DT above/IN series/NN of/IN gradations/NNS from/IN a/DT mass/NN of/IN pollen/NN grains/NNS merely/RB tied/VBN together/RB by/IN threads/NNS ,/, with/IN the/DT stigma/NN differing/VBG but/CC little/JJ from/IN that/IN of/IN an/DT ordinary/JJ flower/NN ,/, to/TO a/DT highly/RB complex/JJ pollinium/NN ,/, admirably/RB adapted/VBN for/IN transportal/JJ by/IN insects/NNS ;/: nor/CC will/MD he/PRP deny/VB that/IN all/DT the/DT gradations/NNS in/IN the/DT several/JJ species/NN are/VBP admirably/RB adapted/VBN in/IN relation/NN to/TO the/DT general/JJ structure/NN of/IN each/DT flower/NN for/IN its/PRP$ fertilisation/NN by/IN different/JJ insects/NNS ./. In/IN this/DT ,/, and/CC in/IN almost/RB every/DT other/JJ case/NN ,/, the/DT enquiry/NN may/MD be/VB pushed/VBD further/JJR backwards/RB ;/: and/CC it/PRP may/MD be/VB asked/VBD how/WRB did/VBD the/DT stigma/NN of/IN an/DT ordinary/JJ flower/NN become/VB viscid/JJ ,/, but/CC as/IN we/PRP do/VBP not/RB know/VB the/DT full/JJ history/NN of/IN any/DT one/CD group/NN of/IN beings/NNS ,/, it/PRP is/VBZ as/IN useless/JJ to/TO ask/VB ,/, as/IN it/PRP is/VBZ hopeless/JJ to/TO attempt/NN answering/VBG ,/, such/JJ questions/NNS ./. We/PRP will/MD now/RB turn/VB to/TO climbing/VBG plants/NNS ./. These/DT can/MD be/VB arranged/VBN in/IN a/DT long/JJ series/NN ,/, from/IN those/DT which/WDT simply/RB twine/NN round/NN a/DT support/NN ,/, to/TO those/DT which/WDT I/PRP have/VBP called/VBN leaf/NN climbers/NNS ,/, and/CC to/TO those/DT provided/VBN with/IN tendrils/NNS ./. In/IN these/DT two/CD latter/NN classes/NNS the/DT stems/VBZ have/VBP generally/RB ,/, but/CC not/RB always/RB ,/, lost/VBD the/DT power/NN of/IN twining/VBG ,/, though/IN they/PRP retain/VB the/DT power/NN of/IN revolving/VBG ,/, which/WDT the/DT tendrils/NNS likewise/RB possess/VBP ./. The/DT gradations/NNS from/IN leaf/NN climbers/NNS to/TO tendril/NN bearers/NNS are/VBP wonderfully/RB close/VB ,/, and/CC certain/JJ plants/NNS may/MD be/VB indifferently/RB placed/VBN in/IN either/DT class/NN ./. But/CC in/IN ascending/VBG the/DT series/NN from/IN simple/JJ twiners/NNS to/TO leaf/NN climbers/NNS ,/, an/DT important/JJ quality/NN is/VBZ added/VBN ,/, namely/RB sensitiveness/NN to/TO a/DT touch/NN ,/, by/IN which/WDT means/VBZ the/DT foot/NN stalks/NNS of/IN the/DT leaves/VBZ or/CC flowers/NNS ,/, or/CC these/DT modified/VBN and/CC converted/VBN into/IN tendrils/NNS ,/, are/VBP excited/VBN to/TO bend/VB round/NN and/CC clasp/NN the/DT touching/VBG object/NN ./. He/PRP who/WP will/MD read/VB my/PRP$ memoir/NN on/IN these/DT plants/NNS will/MD ,/, I/PRP think/VBP ,/, admit/VB that/IN all/DT the/DT many/JJ gradations/NNS in/IN function/NN and/CC structure/NN between/IN simple/JJ twiners/NNS and/CC tendril/NN bearers/NNS are/VBP in/IN each/DT case/NN beneficial/JJ in/IN a/DT high/JJ degree/NN to/TO the/DT species/NN ./. For/IN instance/NN ,/, it/PRP is/VBZ clearly/RB a/DT great/JJ advantage/NN to/TO a/DT twining/VBG plant/NN to/TO become/VB a/DT leaf/NN climber/NN ;/: and/CC it/PRP is/VBZ probable/JJ that/IN every/DT twiner/NN which/WDT possessed/VBD leaves/VBZ with/IN long/JJ foot/NN stalks/NNS would/MD have/VB been/VBN developed/VBN into/IN a/DT leaf/NN climber/NN if/IN the/DT footstalks/NNS had/VBD possessed/VBD in/IN any/DT slight/JJ degree/NN the/DT requisite/JJ sensitiveness/NN to/TO a/DT touch/NN ./. 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By/IN this/DT movement/NN the/DT stems/VBZ are/VBP inclined/VBN to/TO all/DT sides/NNS ,/, and/CC are/VBP made/VBN to/TO move/NN round/NN and/CC round/NN ./. As/IN soon/RB as/IN the/DT lower/JJR part/NN of/IN a/DT stem/VB strikes/NNS against/IN any/DT object/NN and/CC is/VBZ stopped/VBN ,/, the/DT upper/JJ part/NN still/RB goes/VBZ on/IN bending/VBG and/CC revolving/VBG ,/, and/CC thus/RB necessarily/RB twines/NNS round/NN and/CC up/IN the/DT support/NN ./. The/DT revolving/VBG movement/NN ceases/VBZ after/IN the/DT early/JJ growth/NN of/IN each/DT shoot/VB ./. As/IN in/IN many/JJ widely/RB separated/VBN families/NNS of/IN plants/NNS ,/, single/JJ species/NN and/CC single/JJ genera/NN possess/VBP the/DT power/NN of/IN revolving/VBG ,/, and/CC have/VBP thus/RB become/VB twiners/NNS ,/, they/PRP must/MD have/VB independently/RB acquired/VBN it/PRP ,/, and/CC cannot/MD have/VB inherited/VBN it/PRP from/IN a/DT common/JJ progenitor/NN ./. 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I/PRP repeated/VBN these/DT observations/NNS on/IN some/DT other/JJ species/NN of/IN Oxalis/NNP with/IN the/DT same/JJ result/NN ;/: in/IN some/DT of/IN them/PRP the/DT movement/NN was/VBD distinct/JJ ,/, but/CC was/VBD best/JJS seen/VBN in/IN the/DT young/JJ leaves/VBZ ;/: in/IN others/NNS it/PRP was/VBD extremely/RB slight/JJ ./. It/PRP is/VBZ a/DT more/JJR important/JJ fact/NN that/IN according/VBG to/TO the/DT high/JJ authority/NN of/IN Hofmeister/NNP ,/, the/DT young/JJ shoots/VBZ and/CC leaves/VBZ of/IN all/DT plants/NNS move/NN after/IN being/VBG shaken/VBN ;/: and/CC with/IN climbing/VBG plants/NNS it/PRP is/VBZ ,/, as/IN we/PRP know/VB ,/, only/RB during/IN the/DT early/JJ stages/NNS of/IN growth/NN that/IN the/DT foot/NN stalks/NNS and/CC tendrils/NNS are/VBP sensitive/JJ ./. It/PRP is/VBZ scarcely/RB possible/JJ that/IN the/DT above/IN slight/JJ movements/NNS ,/, due/JJ to/TO a/DT touch/NN or/CC shake/VB ,/, in/IN the/DT young/JJ and/CC growing/VBG organs/NNS of/IN plants/NNS ,/, can/MD be/VB of/IN any/DT functional/JJ importance/NN to/TO them/PRP ./. But/CC plants/NNS possess/VBP ,/, in/IN obedience/NN to/TO various/JJ stimuli/NNS ,/, powers/NNS of/IN movement/NN ,/, which/WDT are/VBP of/IN manifest/JJ importance/NN to/TO them/PRP ;/: for/IN instance/NN ,/, towards/IN and/CC more/JJR rarely/RB from/IN the/DT light/NN ,/, in/IN opposition/NN to/TO ,/, and/CC more/JJR rarely/RB in/IN the/DT direction/NN of/IN ,/, the/DT attraction/NN of/IN gravity/NN ./. When/WRB the/DT nerves/NNS and/CC muscles/NNS of/IN an/DT animal/NN are/VBP excited/VBN by/IN galvanism/NN or/CC by/IN the/DT absorption/NN of/IN strychnine/NN ,/, the/DT consequent/JJ movements/NNS may/MD be/VB called/VBN an/DT incidental/JJ result/NN ,/, for/IN the/DT nerves/NNS and/CC muscles/NNS have/VBP not/RB been/VBN rendered/VBN specially/RB sensitive/JJ to/TO these/DT stimuli/NNS ./. So/RB with/IN plants/NNS it/PRP appears/VBZ that/IN ,/, from/IN having/VBG the/DT power/NN of/IN movement/NN in/IN obedience/NN to/TO certain/JJ stimuli/NNS ,/, they/PRP are/VBP excited/VBN in/IN an/DT incidental/JJ manner/NN by/IN a/DT touch/NN ,/, or/CC by/IN being/VBG shaken/VBN ./. Hence/RB there/EX is/VBZ no/DT great/JJ difficulty/NN in/IN admitting/VBG that/IN in/IN the/DT case/NN of/IN leaf/NN climbers/NNS and/CC tendril/NN bearers/NNS ,/, it/PRP is/VBZ this/DT tendency/NN which/WDT has/VBZ been/VBN taken/VBN advantage/NN of/IN and/CC increased/VBN through/IN natural/JJ selection/NN ./. It/PRP is/VBZ ,/, however/RB ,/, probable/JJ ,/, from/IN reasons/NNS which/WDT I/PRP have/VBP assigned/VBN in/IN my/PRP$ memoir/NN ,/, that/IN this/DT will/MD have/VB occurred/VBD only/RB with/IN plants/NNS which/WDT had/VBD already/RB acquired/VBN the/DT power/NN of/IN revolving/VBG ,/, and/CC had/VBD thus/RB become/VB twiners/NNS ./. I/PRP have/VBP already/RB endeavoured/VBN to/TO explain/VB how/WRB plants/NNS became/VBD twiners/NNS ,/, namely/RB ,/, by/IN the/DT increase/NN of/IN a/DT tendency/NN to/TO slight/JJ and/CC irregular/JJ revolving/VBG movements/NNS ,/, which/WDT were/VBD at/IN first/JJ of/IN no/DT use/NN to/TO them/PRP ;/: this/DT movement/NN ,/, as/IN well/RB as/IN that/IN due/JJ to/TO a/DT touch/NN or/CC shake/VB ,/, being/VBG the/DT incidental/JJ result/NN of/IN the/DT power/NN of/IN moving/VBG ,/, gained/VBD for/IN other/JJ and/CC beneficial/JJ purposes/NNS ./. Whether/IN ,/, during/IN the/DT gradual/JJ development/NN of/IN climbing/VBG plants/NNS ,/, natural/JJ selection/NN has/VBZ been/VBN aided/VBN by/IN the/DT inherited/VBN effects/NNS of/IN use/NN ,/, I/PRP will/MD not/RB pretend/VB to/TO decide/VB ;/: but/CC we/PRP know/VB that/IN certain/JJ periodical/NN movements/NNS ,/, for/IN instance/NN the/DT so/RB called/VBN sleep/VB of/IN plants/NNS ,/, are/VBP governed/VBN by/IN habit/NN ./. I/PRP have/VBP now/RB considered/VBN enough/RB ,/, perhaps/RB more/JJR than/IN enough/RB ,/, of/IN the/DT cases/NNS ,/, selected/VBN with/IN care/NN by/IN a/DT skilful/JJ naturalist/NN ,/, to/TO prove/VB that/IN natural/JJ selection/NN is/VBZ incompetent/JJ to/TO account/NN for/IN the/DT incipient/JJ stages/NNS of/IN useful/JJ structures/NNS ;/: and/CC I/PRP have/VBP shown/VBN ,/, as/IN I/PRP hope/NN ,/, that/IN there/EX is/VBZ no/DT great/JJ difficulty/NN on/IN this/DT head/NN ./. A/DT good/JJ opportunity/NN has/VBZ thus/RB been/VBN afforded/VBN for/IN enlarging/VBG a/DT little/JJ on/IN gradations/NNS of/IN structure/NN ,/, often/RB associated/VBN with/IN changed/VBN functions/NNS ,/, an/DT important/JJ subject/NN which/WDT was/VBD not/RB treated/VBN at/IN sufficient/JJ length/NN in/IN the/DT former/JJ editions/NNS of/IN this/DT work/NN ./. I/PRP will/MD now/RB briefly/NN recapitulate/VB the/DT foregoing/NN cases/NNS ./. With/IN the/DT giraffe/NN ,/, the/DT continued/VBD preservation/NN of/IN the/DT individuals/NNS of/IN some/DT extinct/JJ high/JJ reaching/VBG ruminant/NN ,/, which/WDT had/VBD the/DT longest/JJS necks/NNS ,/, legs/NNS ,/, &c/NN ./. ,/, and/CC could/MD browse/VB a/DT little/JJ above/IN the/DT average/JJ height/NN ,/, and/CC the/DT continued/VBD destruction/NN of/IN those/DT which/WDT could/MD not/RB browse/VB so/RB high/JJ ,/, would/MD have/VB sufficed/VBD for/IN the/DT production/NN of/IN this/DT remarkable/JJ quadruped/VBD ;/: but/CC the/DT prolonged/VBN use/NN of/IN all/DT the/DT parts/NNS together/RB with/IN inheritance/NN will/MD have/VB aided/VBN in/IN an/DT important/JJ manner/NN in/IN their/PRP$ co/NN ordination/NN ./. With/IN the/DT many/JJ insects/NNS which/WDT imitate/VB various/JJ objects/NNS ,/, there/EX is/VBZ no/DT improbability/NN in/IN the/DT belief/NN that/IN an/DT accidental/JJ resemblance/NN to/TO some/DT common/JJ object/NN was/VBD in/IN each/DT case/NN the/DT foundation/NN for/IN the/DT work/NN of/IN natural/JJ selection/NN ,/, since/IN perfected/VBN through/IN the/DT occasional/JJ preservation/NN of/IN slight/JJ variations/NNS which/WDT ma/FW de/FW the/DT resemblance/NN at/IN all/DT closer/JJR ;/: and/CC this/DT will/MD have/VB been/VBN carried/VBD on/IN as/IN long/JJ as/IN the/DT insect/NN continued/VBD to/TO vary/VB ,/, and/CC as/IN long/JJ as/IN a/DT more/JJR and/CC more/JJR perfect/JJ resemblance/NN led/VBN to/TO its/PRP$ escape/VB from/IN sharp/JJ sighted/VBN enemies/NNS ./. In/IN certain/JJ species/NN of/IN whales/NNS there/EX is/VBZ a/DT tendency/NN to/TO the/DT formation/NN of/IN irregular/JJ little/JJ points/NNS of/IN horn/NN on/IN the/DT palate/NN ;/: and/CC it/PRP seems/VBZ to/TO be/VB quite/RB within/IN the/DT scope/NN of/IN natural/JJ selection/NN to/TO preserve/VB all/DT favourable/JJ variations/NNS ,/, until/IN the/DT points/NNS were/VBD converted/VBN first/JJ into/IN lamellated/VBN knobs/NNS or/CC teeth/NNS ,/, like/IN those/DT on/IN the/DT beak/NN of/IN a/DT goose/NN ,/, then/RB into/IN short/JJ lamellae/NN ,/, like/IN those/DT of/IN the/DT domestic/JJ ducks/NNS ,/, and/CC then/RB into/IN lamellae/NN ,/, as/IN perfect/JJ as/IN those/DT of/IN the/DT shoveller/NN duck/NN ,/, and/CC finally/RB into/IN the/DT gigantic/JJ plates/NNS of/IN baleen/NN ,/, as/IN in/IN the/DT mouth/NN of/IN the/DT Greenland/NNP whale/NN ./. In/IN the/DT family/NN of/IN the/DT ducks/NNS ,/, the/DT lamellae/NN are/VBP first/JJ used/VBN as/IN teeth/NNS ,/, then/RB partly/RB as/IN teeth/NNS ,/, and/CC partly/RB as/IN a/DT sifting/NN apparatus/NN ,/, and/CC at/IN last/JJ almost/RB exclusively/RB for/IN this/DT latter/NN purpose/NN ./. With/IN such/JJ structures/NNS as/IN the/DT above/IN lamellae/NN of/IN horn/NN or/CC whalebone/NN ,/, habit/NN or/CC use/NN can/MD have/VB done/VBN little/JJ or/CC nothing/NN ,/, as/IN far/RB as/IN we/PRP can/MD judge/NN ,/, towards/IN their/PRP$ development/NN ./. On/IN the/DT other/JJ hand/NN ,/, the/DT transportal/JJ of/IN the/DT lower/JJR eye/NN of/IN a/DT flat/JJ fish/NN to/TO the/DT upper/JJ side/NN of/IN the/DT head/NN ,/, and/CC the/DT formation/NN of/IN a/DT prehensile/NN tail/NN ,/, may/MD be/VB attributed/VBD almost/RB wholly/RB to/TO continued/VBD use/NN ,/, together/RB with/IN inheritance/NN ./. With/IN respect/NN to/TO the/DT mammae/NN of/IN the/DT higher/JJR animals/NNS ,/, the/DT most/RBS probable/JJ conjecture/NN is/VBZ that/IN primordially/RB the/DT cutaneous/JJ glands/NNS over/IN the/DT whole/JJ surface/NN of/IN a/DT marsupial/JJ sack/NN secreted/VBN a/DT nutritious/JJ fluid/NN ;/: and/CC that/IN these/DT glands/NNS were/VBD improved/VBN in/IN function/NN through/IN natural/JJ selection/NN ,/, and/CC concentrated/VBN into/IN a/DT confined/VBN area/NN ,/, in/IN which/WDT case/NN they/PRP would/MD have/VB formed/VBN a/DT mamma/NN ./. There/EX is/VBZ no/DT more/JJR difficulty/NN in/IN understanding/NN how/WRB the/DT branched/VBN spines/NNS of/IN some/DT ancient/JJ echinoderm/NN ,/, which/WDT served/VBN as/IN a/DT defence/NN ,/, became/VBD developed/VBN through/IN natural/JJ selection/NN into/IN tridactyle/NN pedicellariae/NN ,/, than/IN in/IN understanding/NN the/DT development/NN of/IN the/DT pincers/NNS of/IN crustaceans/NNS ,/, through/IN slight/JJ ,/, serviceable/JJ modifications/NNS in/IN the/DT ultimate/JJ and/CC penultimate/JJ segments/NNS of/IN a/DT limb/NN ,/, which/WDT was/VBD at/IN first/JJ used/VBN solely/RB for/IN locomotion/NN ./. In/IN the/DT avicularia/NN and/CC vibracula/NN of/IN the/DT Polyzoa/NNP we/PRP have/VBP organs/NNS widely/RB different/JJ in/IN appearance/NN developed/VBN from/IN the/DT same/JJ source/NN ;/: and/CC with/IN the/DT vibracula/NN we/PRP can/MD understand/VB how/WRB the/DT successive/JJ gradations/NNS might/MD have/VB been/VBN of/IN service/NN ./. With/IN the/DT pollinia/NN of/IN orchids/NNS ,/, the/DT threads/NNS which/WDT originally/RB served/VBN to/TO tie/NN together/RB the/DT pollen/NN grains/NNS ,/, can/MD be/VB traced/VBN cohering/VBG into/IN caudicles/NNS ;/: and/CC the/DT steps/NNS can/MD likewise/RB be/VB followed/VBD by/IN which/WDT viscid/JJ matter/NN ,/, such/JJ as/IN that/IN secreted/VBN by/IN the/DT stigmas/NNS of/IN ordinary/JJ flowers/NNS ,/, and/CC still/RB subserving/VBG nearly/RB but/CC not/RB quite/RB the/DT same/JJ purpose/NN ,/, became/VBD attached/VBN to/TO the/DT free/JJ ends/NNS of/IN the/DT caudicles/NNS ;/: all/DT these/DT gradations/NNS being/VBG of/IN modest/JJ benefit/NN to/TO the/DT plants/NNS in/IN question/NN ./. With/IN respect/NN to/TO climbing/VBG plants/NNS ,/, I/PRP need/NN not/RB repeat/VB what/WP has/VBZ been/VBN so/RB lately/RB said/VBD ./. It/PRP has/VBZ often/RB been/VBN asked/VBD ,/, if/IN natural/JJ selection/NN be/VB so/RB potent/JJ ,/, why/WRB has/VBZ not/RB this/DT or/CC that/IN structure/NN been/VBN gained/VBD by/IN certain/JJ species/NN ,/, to/TO which/WDT it/PRP would/MD apparently/RB have/VBP been/VBN advantageous/JJ ?/. But/CC it/PRP is/VBZ unreasonable/JJ to/TO expect/VB a/DT precise/JJ answer/NN to/TO such/JJ questions/NNS ,/, considering/VBG our/PRP$ ignorance/NN of/IN the/DT past/JJ history/NN of/IN each/DT species/NN ,/, and/CC of/IN the/DT conditions/NNS which/WDT at/IN the/DT present/JJ day/NN determine/VB its/PRP$ numbers/NNS and/CC range/NN ./. In/IN most/RBS cases/NNS only/RB general/JJ reasons/NNS ,/, but/CC in/IN some/DT few/JJ cases/NNS special/JJ reasons/NNS ,/, can/MD be/VB assigned/VBN ./. Thus/RB to/TO adapt/VB a/DT species/NN to/TO new/JJ habits/NNS of/IN life/NN ,/, many/JJ co/NN ordinated/VBN modifications/NNS are/VBP almost/RB indispensable/JJ ,/, and/CC it/PRP may/MD often/RB have/VBP happened/VBD that/IN the/DT requisite/JJ parts/NNS did/VBD not/RB vary/VBP in/IN the/DT right/NN manner/NN or/CC to/TO the/DT right/NN degree/NN ./. Many/JJ species/NN must/MD have/VB been/VBN prevented/VBN from/IN increasing/VBG in/IN numbers/NNS through/IN destructive/JJ agencies/NNS ,/, which/WDT stood/VBD in/IN no/DT relation/NN to/TO certain/JJ structures/NNS ,/, which/WDT we/PRP imagine/VB would/MD have/VB been/VBN gained/VBD through/IN natural/JJ selection/NN from/IN appearing/VBG to/TO us/PRP advantageous/JJ to/TO the/DT species/NN ./. In/IN this/DT case/NN ,/, as/IN the/DT struggle/NN for/IN life/NN did/VBD not/RB depend/VB on/IN such/JJ structures/NNS ,/, they/PRP could/MD not/RB have/VBP been/VBN acquired/VBN through/IN natural/JJ selection/NN ./. In/IN many/JJ cases/NNS complex/JJ and/CC long/JJ enduring/VBG conditions/NNS ,/, often/RB of/IN a/DT peculiar/JJ nature/NN ,/, are/VBP necessary/JJ for/IN the/DT development/NN of/IN a/DT structure/NN ;/: and/CC the/DT requisite/JJ conditions/NNS may/MD seldom/RB have/VBP concurred/VBD ./. The/DT belief/NN that/IN any/DT given/VBN structure/NN ,/, which/WDT we/PRP think/VBP ,/, often/RB erroneously/RB ,/, would/MD have/VB been/VBN beneficial/JJ to/TO a/DT species/NN ,/, would/MD have/VB been/VBN gained/VBD under/IN all/DT circumstances/NNS through/IN natural/JJ selection/NN ,/, is/VBZ opposed/VBN to/TO what/WP we/PRP can/MD understand/VB of/IN its/PRP$ manner/NN of/IN action/NN ./. Mr/NNP ./. Mivart/NNP does/VBZ not/RB deny/VB that/IN natural/JJ selection/NN has/VBZ effected/VBN something/NN ;/: but/CC he/PRP considers/VBZ it/PRP as/IN "/" demonstrably/RB insufficient/JJ "/" to/TO account/NN for/IN the/DT phenomena/NNS which/WDT I/PRP explain/VB by/IN its/PRP$ agency/NN ./. His/PRP$ chief/JJ arguments/NNS have/VBP now/RB been/VBN considered/VBN ,/, and/CC the/DT others/NNS will/MD hereafter/RB be/VB considered/VBN ./. They/PRP seem/VB to/TO me/PRP to/TO partake/VB little/JJ of/IN the/DT character/NN of/IN demonstration/NN ,/, and/CC to/TO have/VB little/JJ weight/NN in/IN comparison/NN with/IN those/DT in/IN favour/NN of/IN the/DT power/NN of/IN natural/JJ selection/NN ,/, aided/VBN by/IN the/DT other/JJ agencies/NNS often/RB specified/VBN ./. I/PRP am/VBP bound/VBN to/TO add/VB ,/, that/IN some/DT of/IN the/DT facts/NNS and/CC arguments/NNS here/RB used/VBN by/IN me/PRP ,/, have/VBP been/VBN advanced/VBD for/IN the/DT same/JJ purpose/NN in/IN an/DT able/JJ article/NN lately/RB published/VBN in/IN the/DT Medico/NNP Chirurgical/NNP Review/NNP ./. At/IN the/DT present/JJ day/NN almost/RB all/DT naturalists/NNS admit/VB evolution/NN under/IN some/DT form/NN ./. Mr/NNP ./. Mivart/NNP believes/VBZ that/IN species/NN change/NN through/IN "/" an/DT internal/JJ force/NN or/CC tendency/NN ,/, "/" about/IN which/WDT it/PRP is/VBZ not/RB pretended/VBD that/IN anything/NN is/VBZ known/VBN ./. That/DT species/NN have/VBP a/DT capacity/NN for/IN change/NN will/MD be/VB admitted/VBD by/IN all/DT evolutionists/NNS ;/: but/CC there/EX is/VBZ no/DT need/NN ,/, as/IN it/PRP seems/VBZ to/TO me/PRP ,/, to/TO invoke/VB any/DT internal/JJ force/NN beyond/IN the/DT tendency/NN to/TO ordinary/JJ variability/NN ,/, which/WDT through/IN the/DT aid/NN of/IN selection/NN by/IN man/NN has/VBZ given/VBN rise/NN to/TO many/JJ well/RB adapted/VBN domestic/JJ races/NNS ,/, and/CC which/WDT through/IN the/DT aid/NN of/IN natural/JJ selection/NN would/MD equally/RB well/RB give/VB rise/NN by/IN graduated/VBN steps/NNS to/TO natural/JJ races/NNS or/CC species/NN ./. The/DT final/JJ result/NN will/MD generally/RB have/VBP been/VBN ,/, as/IN already/RB explained/VBD ,/, an/DT advance/NN ,/, but/CC in/IN some/DT few/JJ cases/NNS a/DT retrogression/NN ,/, in/IN organisation/NN ./. Mr/NNP ./. Mivart/NNP is/VBZ further/JJR inclined/VBN to/TO believe/VB ,/, and/CC some/DT naturalists/NNS agree/VB with/IN him/PRP ,/, that/IN new/JJ species/NN manifest/JJ themselves/PRP "/" with/IN suddenness/NN and/CC by/IN modifications/NNS appearing/VBG at/IN once/RB ./. "/" For/IN instance/NN ,/, he/PRP supposes/VBZ that/IN the/DT differences/NNS between/IN the/DT extinct/JJ three/CD toed/VBN Hipparion/NNP and/CC the/DT horse/NN arose/VBD suddenly/RB ./. He/PRP thinks/VBZ it/PRP difficult/JJ to/TO believe/VB that/IN the/DT wing/NN of/IN a/DT bird/NN "/" was/VBD developed/VBN in/IN any/DT other/JJ way/NN than/IN by/IN a/DT comparatively/RB sudden/JJ modification/NN of/IN a/DT marked/VBN and/CC important/JJ kind/NN "/" ;/: and/CC apparently/RB he/PRP would/MD extend/VB the/DT same/JJ view/NN to/TO the/DT wings/NNS of/IN bats/NNS and/CC pterodactyles/NNS ./. This/DT conclusion/NN ,/, which/WDT implies/VBZ great/JJ breaks/NNS or/CC discontinuity/NN in/IN the/DT series/NN ,/, appears/VBZ to/TO me/PRP improbable/JJ in/IN the/DT highest/JJS degree/NN ./. Every/DT one/CD who/WP believes/VBZ in/IN slow/JJ and/CC gradual/JJ evolution/NN ,/, will/MD of/IN course/NN admit/VB that/IN specific/JJ changes/NNS may/MD have/VB been/VBN as/IN abrupt/JJ and/CC as/IN great/JJ as/IN any/DT single/JJ variation/NN which/WDT we/PRP meet/VB with/IN under/IN nature/NN ,/, or/CC even/RB under/IN domestication/NN ./. But/CC as/IN species/NN are/VBP more/JJR variable/JJ when/WRB domesticated/VBN or/CC cultivated/VBN than/IN under/IN their/PRP$ natural/JJ conditions/NNS ,/, it/PRP is/VBZ not/RB probable/JJ that/IN such/JJ great/JJ and/CC abrupt/JJ variations/NNS have/VBP often/RB occurred/VBD under/IN nature/NN ,/, as/IN are/VBP known/VBN occasionally/RB to/TO arise/VB under/IN domestication/NN ./. Of/IN these/DT latter/NN variations/NNS several/JJ may/MD be/VB attributed/VBD to/TO reversion/NN ;/: and/CC the/DT characters/NNS which/WDT thus/RB reappear/VBP were/VBD ,/, it/PRP is/VBZ probable/JJ ,/, in/IN many/JJ cases/NNS at/IN first/JJ gained/VBD in/IN a/DT gradual/JJ manner/NN ./. A/DT still/RB greater/JJR number/NN must/MD be/VB called/VBN monstrosities/NNS ,/, such/JJ as/IN six/CD fingered/VBD men/NNS ,/, porcupine/NN men/NNS ,/, Ancon/NNP sheep/NN ,/, Niata/NNP cattle/NNS ,/, &c/NN ./. ;/: and/CC as/IN they/PRP are/VBP widely/RB different/JJ in/IN character/NN from/IN natural/JJ species/NN ,/, they/PRP throw/VB very/RB little/JJ light/NN on/IN our/PRP$ subject/NN ./. Excluding/VBG such/JJ cases/NNS of/IN abrupt/JJ variations/NNS ,/, the/DT few/JJ which/WDT remain/VB would/MD at/IN best/JJS constitute/VBP ,/, if/IN found/VBD in/IN a/DT state/NN of/IN nature/NN ,/, doubtful/JJ species/NN ,/, closely/RB related/VBN to/TO their/PRP$ parental/JJ types/NNS ./. My/PRP$ reasons/NNS for/IN doubting/VBG whether/IN natural/JJ species/NN have/VBP changed/VBN as/IN abruptly/RB as/IN have/VBP occasionally/RB domestic/JJ races/NNS ,/, and/CC for/IN entirely/RB disbelieving/VBG that/IN they/PRP have/VBP changed/VBN in/IN the/DT wonderful/JJ manner/NN indicated/VBD by/IN Mr/NNP ./. Mivart/NNP ,/, are/VBP as/IN follows/VBZ ./. According/VBG to/TO our/PRP$ experience/NN ,/, abrupt/JJ and/CC strongly/RB marked/VBN variations/NNS occur/VB in/IN our/PRP$ domesticated/VBN productions/NNS ,/, singly/RB and/CC at/IN rather/RB long/JJ intervals/NNS of/IN time/NN ./. If/IN such/JJ occurred/VBD under/IN nature/NN ,/, they/PRP would/MD be/VB liable/JJ ,/, as/IN formerly/RB explained/VBD ,/, to/TO be/VB lost/VBD by/IN accidental/JJ causes/NNS of/IN destruction/NN and/CC by/IN subsequent/JJ inter/FW crossing/VBG ;/: and/CC so/RB it/PRP is/VBZ known/VBN to/TO be/VB under/IN domestication/NN ,/, unless/IN abrupt/JJ variations/NNS of/IN this/DT kind/NN are/VBP specially/RB preserved/VBN and/CC separated/VBN by/IN the/DT care/NN of/IN man/NN ./. Hence/RB in/IN order/NN that/IN a/DT new/JJ species/NN should/MD suddenly/RB appear/VB in/IN the/DT manner/NN supposed/VBN by/IN Mr/NNP ./. Mivart/NNP ,/, it/PRP is/VBZ almost/RB necessary/JJ to/TO believe/VB ,/, in/IN opposition/NN to/TO all/DT analogy/NN ,/, that/IN several/JJ wonderfully/RB changed/VBN individuals/NNS appeared/VBD simultaneously/RB within/IN the/DT same/JJ district/NN ./. This/DT difficulty/NN ,/, as/IN in/IN the/DT case/NN of/IN unconscious/JJ selection/NN by/IN man/NN ,/, is/VBZ avoided/VBN on/IN the/DT theory/NN of/IN gradual/JJ evolution/NN ,/, through/IN the/DT preservation/NN of/IN a/DT large/JJ number/NN of/IN individuals/NNS ,/, which/WDT varied/VBN more/JJR or/CC less/JJR in/IN any/DT favourable/JJ direction/NN ,/, and/CC of/IN the/DT destruction/NN of/IN a/DT large/JJ number/NN which/WDT varied/VBN in/IN an/DT opposite/JJ manner/NN ./. That/DT many/JJ species/NN have/VBP been/VBN evolved/VBN in/IN an/DT extremely/RB gradual/JJ manner/NN ,/, there/EX can/MD hardly/RB be/VB a/DT doubt/NN ./. The/DT species/NN and/CC even/RB the/DT genera/NN of/IN many/JJ large/JJ natural/JJ families/NNS are/VBP so/RB closely/RB allied/VBN together/RB ,/, that/IN it/PRP is/VBZ difficult/JJ to/TO distinguish/VB not/RB a/DT few/JJ of/IN them/PRP ./. On/IN every/DT continent/NN in/IN proceeding/NN from/IN north/RB to/TO south/RB ,/, from/IN lowland/NN to/TO upland/JJ ,/, &c/NN ./. ,/, we/PRP meet/VB with/IN a/DT host/NN of/IN closely/RB related/VBN or/CC representative/NN species/NN ;/: as/IN we/PRP likewise/RB do/VBP on/IN certain/JJ distinct/JJ continents/NNS ,/, which/WDT we/PRP have/VBP reason/NN to/TO believe/VB were/VBD formerly/RB connected/VBN ./. But/CC in/IN making/VBG these/DT and/CC the/DT following/VBG remarks/NNS ,/, I/PRP am/VBP compelled/VBN to/TO allude/NN to/TO subjects/NNS hereafter/RB to/TO be/VB discussed/VBN ./. Look/VB at/IN the/DT many/JJ outlying/JJ islands/NNS round/NN a/DT continent/NN ,/, and/CC see/VB how/WRB many/JJ of/IN their/PRP$ inhabitants/NNS can/MD be/VB raised/VBN only/RB to/TO the/DT rank/NN of/IN doubtful/JJ species/NN ./. So/RB it/PRP is/VBZ if/IN we/PRP look/VB to/TO past/JJ times/NNS ,/, and/CC compare/VB the/DT species/NN which/WDT have/VBP just/RB passed/VBN away/RB with/IN those/DT still/RB living/VBG within/IN the/DT same/JJ areas/NNS ;/: or/CC if/IN we/PRP compare/VB the/DT fossil/JJ species/NN embedded/VBN in/IN the/DT sub/NN stages/NNS of/IN the/DT same/JJ geological/JJ formation/NN ./. It/PRP is/VBZ indeed/RB manifest/JJ that/IN multitudes/NNS of/IN species/NN are/VBP related/VBN in/IN the/DT closest/JJS manner/NN to/TO other/JJ species/NN that/IN still/RB exist/VB ,/, or/CC have/VBP lately/RB existed/VBD ;/: and/CC it/PRP will/MD hardly/RB be/VB maintained/VBN that/IN such/JJ species/NN have/VBP been/VBN developed/VBN in/IN an/DT abrupt/JJ or/CC sudden/JJ manner/NN ./. Nor/CC should/MD it/PRP be/VB forgotten/VBN ,/, when/WRB we/PRP look/VB to/TO the/DT special/JJ parts/NNS of/IN allied/VBN species/NN ,/, instead/RB of/IN to/TO distinct/JJ species/NN ,/, that/IN numerous/JJ and/CC wonderfully/RB fine/JJ gradations/NNS can/MD be/VB traced/VBN ,/, connecting/VBG together/RB widely/RB different/JJ structures/NNS ./. Many/JJ large/JJ groups/NNS of/IN facts/NNS are/VBP intelligible/JJ only/RB on/IN the/DT principle/NN that/IN species/NN have/VBP been/VBN evolved/VBN by/IN very/RB small/JJ steps/NNS :/: for/IN instance/NN ,/, the/DT fact/NN that/IN the/DT species/NN included/VBD in/IN the/DT larger/JJR genera/NN are/VBP more/JJR closely/RB related/VBN to/TO each/DT other/JJ ,/, and/CC present/JJ a/DT greater/JJR number/NN of/IN varieties/NNS than/IN do/VBP the/DT species/NN in/IN the/DT smaller/JJR genera/NN ./. 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Although/IN very/RB many/JJ species/NN have/VBP almost/RB certainly/RB been/VBN produced/VBN by/IN steps/NNS not/RB greater/JJR than/IN those/DT separating/VBG fine/JJ varieties/NNS ;/: yet/RB it/PRP may/MD be/VB maintained/VBN that/IN some/DT have/VBP been/VBN developed/VBN in/IN a/DT different/JJ and/CC abrupt/JJ manner/NN ./. Such/JJ an/DT admission/NN ,/, however/RB ,/, ought/MD not/RB to/TO be/VB made/VBN without/IN strong/JJ evidence/NN being/VBG assigned/VBN ./. The/DT vague/JJ and/CC in/IN some/DT respects/NNS false/JJ analogies/NNS ,/, as/IN they/PRP have/VBP been/VBN shown/VBN to/TO be/VB by/IN Mr/NNP ./. Chauncey/NNP Wright/NNP ,/, which/WDT have/VBP been/VBN advanced/VBD in/IN favour/NN of/IN this/DT view/NN ,/, such/JJ as/IN the/DT sudden/JJ crystallisation/NN of/IN inorganic/JJ substances/NNS ,/, or/CC the/DT falling/VBG of/IN a/DT facetted/VBN spheroid/JJ from/IN one/CD facet/NN to/TO another/DT ,/, hardly/RB deserve/VBP consideration/NN ./. 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Embryological/NNP resemblances/NNS of/IN all/DT kinds/NNS can/MD be/VB accounted/VBD for/IN ,/, as/IN we/PRP shall/MD hereafter/RB see/VB ,/, by/IN the/DT progenitors/NNS of/IN our/PRP$ existing/VBG species/NN having/VBG varied/VBN after/IN early/JJ youth/NN ,/, and/CC having/VBG transmitted/VBN their/PRP$ newly/RB acquired/VBN characters/NNS to/TO their/PRP$ offspring/NN ,/, at/IN a/DT corresponding/JJ age/NN ./. The/DT embryo/NN is/VBZ thus/RB left/VBN almost/RB unaffected/JJ ,/, and/CC serves/VBZ as/IN a/DT record/NN of/IN the/DT past/JJ condition/NN of/IN the/DT species/NN ./. Hence/RB it/PRP is/VBZ that/IN existing/VBG species/NN during/IN the/DT early/JJ stages/NNS of/IN their/PRP$ development/NN so/RB often/RB resemble/VB ancient/JJ and/CC extinct/JJ forms/NNS belonging/VBG to/TO the/DT same/JJ class/NN ./. On/IN this/DT view/NN of/IN the/DT meaning/NN of/IN embryological/JJ resemblances/NNS ,/, and/CC indeed/RB on/IN any/DT view/NN ,/, it/PRP is/VBZ incredible/JJ that/IN an/DT animal/NN should/MD have/VB undergone/VBN such/JJ momentous/JJ and/CC abrupt/JJ transformations/NNS ,/, as/IN those/DT above/IN indicated/VBD ;/: and/CC yet/RB should/MD not/RB bear/VB even/RB a/DT trace/NN in/IN its/PRP$ embryonic/JJ condition/NN of/IN any/DT sudden/JJ modification/NN ;/: every/DT detail/NN in/IN its/PRP$ structure/NN being/VBG developed/VBN by/IN insensibly/RB fine/JJ steps/NNS ./. He/PRP who/WP believes/VBZ that/IN some/DT ancient/JJ form/NN was/VBD transformed/VBN suddenly/RB through/IN an/DT internal/JJ force/NN or/CC tendency/NN into/IN ,/, for/IN instance/NN ,/, one/CD furnished/VBN with/IN wings/NNS ,/, will/MD be/VB almost/RB compelled/VBN to/TO assume/VB ,/, in/IN opposition/NN to/TO all/DT analogy/NN ,/, that/IN many/JJ individuals/NNS varied/VBN simultaneously/RB ./. 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To/TO admit/VB all/DT this/DT is/VBZ ,/, as/IN it/PRP seems/VBZ to/TO me/PRP ,/, to/TO enter/VB into/IN the/DT realms/NNS of/IN miracle/NN ,/, and/CC to/TO leave/VB those/DT of/IN Science/NNP ./. CHAPTER/NNP VIII/NNP INSTINCT/NNP MANY/JJ instincts/NNS are/VBP so/RB wonderful/JJ that/IN their/PRP$ development/NN will/MD probably/RB appear/VB to/TO the/DT reader/NN a/DT difficulty/NN sufficient/JJ to/TO overthrow/VB my/PRP$ whole/JJ theory/NN ./. I/PRP may/MD here/RB premise/NN that/IN I/PRP have/VBP nothing/NN to/TO do/VB with/IN the/DT origin/NN of/IN the/DT mental/JJ powers/NNS ,/, any/DT more/JJR than/IN I/PRP have/VBP with/IN that/IN of/IN life/NN itself/PRP ./. We/PRP are/VBP concerned/VBN only/RB with/IN the/DT diversities/NNS of/IN instinct/NN and/CC of/IN the/DT other/JJ mental/JJ faculties/NNS in/IN animals/NNS of/IN the/DT same/JJ class/NN ./. I/PRP will/MD not/RB attempt/NN any/DT definition/NN of/IN instinct/NN ./. It/PRP would/MD be/VB easy/JJ to/TO show/NN that/IN several/JJ distinct/JJ mental/JJ actions/NNS are/VBP commonly/RB embraced/VBN by/IN this/DT term/NN ;/: but/CC every/DT one/CD understands/VBZ what/WP is/VBZ meant/VBN ,/, when/WRB it/PRP is/VBZ said/VBD that/IN instinct/NN impels/VBZ the/DT cuckoo/NN to/TO migrate/VB and/CC to/TO lay/VBD her/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ./. An/DT action/NN ,/, which/WDT we/PRP ourselves/PRP require/VB experience/NN to/TO enable/VB us/PRP to/TO perform/VB ,/, when/WRB performed/VBN by/IN an/DT animal/NN ,/, more/JJR especially/RB by/IN a/DT very/RB young/JJ one/CD ,/, without/IN experience/NN ,/, and/CC when/WRB performed/VBN by/IN many/JJ individuals/NNS in/IN the/DT same/JJ way/NN ,/, without/IN their/PRP$ knowing/VBG for/IN what/WP purpose/NN it/PRP is/VBZ performed/VBN ,/, is/VBZ usually/RB said/VBD to/TO be/VB instinctive/JJ ./. But/CC I/PRP could/MD show/NN that/IN none/NN of/IN these/DT characters/NNS are/VBP universal/JJ ./. A/DT little/JJ dose/NN of/IN judgment/NN or/CC reason/NN ,/, as/IN Pierre/NNP Huber/NNP expresses/VBZ it/PRP ,/, often/RB comes/VBZ into/IN play/VB ,/, even/RB with/IN animals/NNS low/JJ in/IN the/DT scale/NN of/IN nature/NN ./. Frederic/NNP Cuvier/NNP and/CC several/JJ of/IN the/DT older/JJR metaphysicians/NNS have/VBP compared/VBN instinct/NN with/IN habit/NN ./. This/DT comparison/NN gives/VBZ ,/, I/PRP think/VBP ,/, an/DT accurate/JJ notion/NN of/IN the/DT frame/NN of/IN mind/NN under/IN which/WDT an/DT instinctive/JJ action/NN is/VBZ performed/VBN ,/, but/CC not/RB necessarily/RB of/IN its/PRP$ origin/NN ./. How/WRB unconsciously/RB many/JJ habitual/JJ actions/NNS are/VBP performed/VBN ,/, indeed/RB not/RB rarely/RB in/IN direct/JJ opposition/NN to/TO our/PRP$ conscious/JJ will!/NN Yet/RB they/PRP may/MD be/VB modified/VBN by/IN the/DT will/MD or/CC reason/NN ./. 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But/CC I/PRP believe/VBP that/IN the/DT effects/NNS of/IN habit/NN are/VBP in/IN many/JJ cases/NNS of/IN subordinate/JJ importance/NN to/TO the/DT effects/NNS of/IN the/DT natural/JJ selection/NN of/IN what/WP may/MD be/VB called/VBN spontaneous/JJ variations/NNS of/IN instincts/NNS ;/: that/IN is/VBZ of/IN variations/NNS produced/VBN by/IN the/DT same/JJ unknown/JJ causes/NNS which/WDT produce/VB slight/JJ deviations/NNS of/IN bodily/JJ structure/NN ./. No/DT complex/JJ instinct/NN can/MD possibly/RB be/VB produced/VBN through/IN natural/JJ selection/NN ,/, except/IN by/IN the/DT slow/JJ and/CC gradual/JJ accumulation/NN of/IN numerous/JJ slight/JJ ,/, yet/RB profitable/JJ ,/, variations/NNS ./. 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I/PRP have/VBP been/VBN surprised/VBN to/TO find/VB ,/, making/VBG allowance/NN for/IN the/DT instincts/NNS of/IN animals/NNS having/VBG been/VBN but/CC little/JJ observed/VBN except/IN in/IN Europe/NNP and/CC North/NNP America/NNP ,/, and/CC for/IN no/DT instinct/NN being/VBG known/VBN amongst/IN extinct/JJ species/NN ,/, how/WRB very/RB generally/RB gradations/NNS ,/, leading/VBG to/TO the/DT most/RBS complex/JJ instincts/NNS ,/, can/MD be/VB discovered/VBN ./. Changes/NNS of/IN instinct/NN may/MD sometimes/RB be/VB facilitated/VBN by/IN the/DT same/JJ species/NN having/VBG different/JJ instincts/NNS at/IN different/JJ periods/NNS of/IN life/NN ,/, or/CC at/IN different/JJ seasons/NNS of/IN the/DT year/NN ,/, or/CC when/WRB placed/VBN under/IN different/JJ circumstances/NNS ,/, &c/NN ;/: in/IN which/WDT case/NN either/DT the/DT one/CD or/CC the/DT other/JJ instinct/NN might/MD be/VB preserved/VBN by/IN natural/JJ selection/NN ./. And/CC such/JJ instances/NNS of/IN diversity/NN of/IN instinct/NN in/IN the/DT same/JJ species/NN can/MD be/VB shown/VBN to/TO occur/VB in/IN nature/NN ./. Again/RB ,/, as/IN in/IN the/DT case/NN of/IN corporeal/JJ structure/NN ,/, and/CC conformably/RB to/TO my/PRP$ theory/NN ,/, the/DT instinct/NN of/IN each/DT species/NN is/VBZ good/JJ for/IN itself/PRP ,/, but/CC has/VBZ never/RB ,/, as/IN far/RB as/IN we/PRP can/MD judge/NN ,/, been/VBN produced/VBN for/IN the/DT exclusive/JJ good/JJ of/IN others/NNS ./. One/CD of/IN the/DT strongest/JJS instances/NNS of/IN an/DT animal/NN apparently/RB performing/VBG an/DT action/NN for/IN the/DT sole/JJ good/JJ of/IN another/DT ,/, with/IN which/WDT I/PRP am/VBP acquainted/VBN ,/, is/VBZ that/IN of/IN aphides/NNS voluntarily/RB yielding/VBG ,/, as/IN was/VBD first/JJ observed/VBN by/IN Huber/NNP ,/, their/PRP$ sweet/JJ excretion/NN to/TO ants/NNS :/: that/IN they/PRP do/VBP so/RB voluntarily/RB ,/, the/DT following/VBG facts/NNS show/NN ./. I/PRP removed/VBN all/DT the/DT ants/NNS from/IN a/DT group/NN of/IN about/IN a/DT dozen/NN aphides/NNS on/IN a/DT dock/NN plant/NN ,/, and/CC prevented/VBN their/PRP$ attendance/NN during/IN several/JJ hours/NNS ./. After/IN this/DT interval/NN ,/, I/PRP felt/VBD sure/JJ that/IN the/DT aphides/NNS would/MD want/VB to/TO excrete/VB ./. I/PRP watched/VBD them/PRP for/IN some/DT time/NN through/IN a/DT lens/NN ,/, but/CC not/RB one/CD excreted/VBN ;/: I/PRP then/RB tickled/VBD and/CC stroked/VBD them/PRP with/IN a/DT hair/NN in/IN the/DT same/JJ manner/NN ,/, as/IN well/RB as/IN I/PRP could/MD ,/, as/IN the/DT ants/NNS do/VBP with/IN their/PRP$ antennae/NNS ;/: but/CC not/RB one/CD excreted/VBN ./. Afterwards/RB I/PRP allowed/VBN an/DT ant/NN to/TO visit/NN them/PRP ,/, and/CC it/PRP immediately/RB seemed/VBD ,/, by/IN its/PRP$ eager/JJ way/NN of/IN running/VBG about/IN ,/, to/TO be/VB well/RB aware/JJ what/WP a/DT rich/JJ flock/NN it/PRP had/VBD discovered/VBN ;/: it/PRP then/RB began/VBD to/TO play/VB with/IN its/PRP$ antennae/NNS on/IN the/DT abdomen/NN first/JJ of/IN one/CD aphis/RB and/CC then/RB of/IN another/DT ;/: and/CC each/DT ,/, as/IN soon/RB as/IN it/PRP felt/VBD the/DT antennae/NNS ,/, immediately/RB lifted/VBD up/IN its/PRP$ abdomen/NN and/CC excreted/VBN a/DT limpid/JJ drop/NN of/IN sweet/JJ juice/NN ,/, which/WDT was/VBD eagerly/RB devoured/VBN by/IN the/DT ant/NN ./. Even/RB the/DT quite/RB young/JJ aphides/NNS behaved/VBD in/IN this/DT manner/NN ,/, showing/VBG that/IN the/DT action/NN was/VBD instinctive/JJ ,/, and/CC not/RB the/DT result/NN of/IN experience/NN ./. It/PRP is/VBZ certain/JJ ,/, from/IN the/DT observations/NNS of/IN Huber/NNP ,/, that/IN the/DT aphides/NNS show/NN no/DT dislike/NN to/TO the/DT ants/NNS :/: if/IN the/DT latter/NN be/VB not/RB present/JJ they/PRP are/VBP at/IN last/JJ compelled/VBN to/TO eject/VB their/PRP$ excretion/NN ./. But/CC as/IN the/DT excretion/NN is/VBZ extremely/RB viscid/JJ ,/, it/PRP is/VBZ no/DT doubt/NN a/DT convenience/NN to/TO the/DT aphides/NNS to/TO have/VB it/PRP removed/VBN ;/: therefore/RB probably/RB they/PRP do/VBP not/RB excrete/VB solely/RB for/IN the/DT good/JJ of/IN the/DT ants/NNS ./. Although/IN there/EX is/VBZ no/DT evidence/NN that/IN any/DT animal/NN performs/VBZ an/DT action/NN for/IN the/DT exclusive/JJ good/JJ of/IN another/DT species/NN ,/, yet/RB each/DT tries/VBZ to/TO take/VB advantage/NN of/IN the/DT instincts/NNS of/IN others/NNS ,/, as/IN each/DT takes/VBZ advantage/NN of/IN the/DT weaker/JJR bodily/JJ structure/NN of/IN other/JJ species/NN ./. So/RB again/RB instincts/NNS cannot/MD be/VB considered/VBN as/IN absolutely/RB perfect/JJ ;/: but/CC as/IN details/NNS on/IN this/DT and/CC other/JJ such/JJ points/NNS are/VBP not/RB indispensable/JJ ,/, they/PRP may/MD be/VB here/RB passed/VBN over/IN ./. As/IN some/DT degree/NN of/IN variation/NN in/IN instincts/NNS under/IN a/DT state/NN of/IN nature/NN ,/, and/CC the/DT inheritance/NN of/IN such/JJ variations/NNS ,/, are/VBP indispensable/JJ for/IN the/DT action/NN of/IN natural/JJ selection/NN ,/, as/IN many/JJ instances/NNS as/IN possible/JJ ought/MD to/TO be/VB given/VBN ;/: but/CC want/VBP of/IN space/NN prevents/VBZ me/PRP ./. I/PRP can/MD only/RB assert/VB that/IN instincts/NNS certainly/RB do/VBP vary/VBP for/IN instance/NN ,/, the/DT migratory/JJ instinct/NN ,/, both/DT in/IN extent/NN and/CC direction/NN ,/, and/CC in/IN its/PRP$ total/JJ loss/NN ./. So/RB it/PRP is/VBZ with/IN the/DT nests/NNS of/IN birds/NNS ,/, which/WDT vary/VBP partly/RB in/IN dependence/NN on/IN the/DT situations/NNS chosen/VBN ,/, and/CC on/IN the/DT nature/NN and/CC temperature/NN of/IN the/DT country/NN inhabited/VBN ,/, but/CC often/RB from/IN causes/NNS wholly/RB unknown/JJ to/TO us/PRP :/: Audubon/NNP has/VBZ given/VBN several/JJ remarkable/JJ cases/NNS of/IN differences/NNS in/IN the/DT nests/NNS of/IN the/DT same/JJ species/NN in/IN the/DT northern/JJ and/CC southern/JJ United/NNP States/NNPS ./. Why/WRB ,/, it/PRP has/VBZ been/VBN asked/VBD ,/, if/IN instinct/NN be/VB variable/JJ ,/, has/VBZ it/PRP not/RB granted/VBN to/TO the/DT bee/NN "/" the/DT ability/NN to/TO use/NN some/DT other/JJ material/NN when/WRB wax/NN was/VBD deficient/JJ "/" ?/. But/CC what/WP other/JJ natural/JJ material/NN could/MD bees/NNS use/NN ?/. They/PRP will/MD work/NN ,/, as/IN I/PRP have/VBP seen/VBN ,/, with/IN wax/NN hardened/VBN with/IN vermilion/JJ or/CC softened/VBD with/IN lard/NN ./. Andrew/NNP Knight/NNP observed/VBN that/IN his/PRP$ bees/NNS ,/, instead/RB of/IN laboriously/RB collecting/VBG propolis/NN ,/, used/VBN a/DT cement/NN of/IN wax/NN and/CC turpentine/NN ,/, with/IN which/WDT he/PRP had/VBD covered/VBN decorticated/VBN trees/NNS ./. It/PRP has/VBZ lately/RB been/VBN shown/VBN that/IN bees/NNS ,/, instead/RB of/IN searching/VBG for/IN pollen/NN ,/, will/MD gladly/RB use/NN a/DT very/RB different/JJ substance/NN ,/, namely/RB oatmeal/NN ./. Fear/NN of/IN any/DT particular/JJ enemy/NN is/VBZ certainly/RB an/DT instinctive/JJ quality/NN ,/, as/IN may/MD be/VB seen/VBN in/IN nestling/NN birds/NNS ,/, though/IN it/PRP is/VBZ strengthened/VBN by/IN experience/NN ,/, and/CC by/IN the/DT sight/NN of/IN fear/NN of/IN the/DT same/JJ enemy/NN in/IN other/JJ animals/NNS ./. 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That/DT the/DT mental/JJ qualities/NNS of/IN animals/NNS of/IN the/DT same/JJ kind/NN ,/, born/VBN in/IN a/DT state/NN of/IN nature/NN ,/, vary/VBP much/JJ ,/, could/MD be/VB shown/VBN by/IN many/JJ facts/NNS ./. Several/JJ cases/NNS could/MD also/RB be/VB adduced/VBN of/IN occasional/JJ and/CC strange/JJ habits/NNS in/IN wild/JJ animals/NNS ,/, which/WDT ,/, if/IN advantageous/JJ to/TO the/DT species/NN ,/, might/MD have/VB given/VBN rise/NN ,/, through/IN natural/JJ selection/NN ,/, to/TO new/JJ instincts/NNS ./. But/CC I/PRP am/VBP well/RB aware/JJ that/IN these/DT general/JJ statements/NNS ,/, without/IN the/DT facts/NNS in/IN detail/NN ,/, will/MD produce/VB but/CC a/DT feeble/JJ effect/NN on/IN the/DT reader's/NNS mind/NN ./. I/PRP can/MD only/RB repeat/VB my/PRP$ assurance/NN ,/, that/IN I/PRP do/VBP not/RB speak/VB without/IN good/JJ evidence/NN ./. Inherited/VBN Changes/NNS of/IN Habit/NNP or/CC Instinct/NNP in/IN Domesticated/VBN Animals/NNS The/DT possibility/NN ,/, or/CC even/RB probability/NN ,/, of/IN inherited/VBN variations/NNS of/IN instinct/NN in/IN a/DT state/NN of/IN nature/NN will/MD be/VB strengthened/VBN by/IN briefly/NN considering/VBG a/DT few/JJ cases/NNS under/IN domestication/NN ./. We/PRP shall/MD thus/RB be/VB enabled/VBD to/TO see/VB the/DT part/NN which/WDT habit/NN and/CC the/DT selection/NN of/IN so/RB called/VBN spontaneous/JJ variations/NNS have/VBP played/VBD in/IN modifying/VBG the/DT mental/JJ qualities/NNS of/IN our/PRP$ domestic/JJ animals/NNS ./. It/PRP is/VBZ notorious/JJ how/WRB much/JJ domestic/JJ animals/NNS vary/VBP in/IN their/PRP$ mental/JJ qualities/NNS ./. With/IN cats/NNS ,/, for/IN instance/NN ,/, one/CD naturally/RB takes/VBZ to/TO catching/VBG rats/NNS ,/, and/CC another/DT mice/NNS ,/, and/CC these/DT tendencies/NNS are/VBP known/VBN to/TO be/VB inherited/VBN ./. One/CD cat/NN ,/, according/VBG to/TO Mr/NNP ./. St/NNP ./. John/NNP ,/, always/RB brought/VBN home/NN gamebirds/NNS ,/, another/DT hares/NNS or/CC rabbits/NNS ,/, and/CC another/DT hunted/VBN on/IN marshy/NN ground/NN and/CC almost/RB nightly/JJ caught/VBN woodcocks/NNS or/CC snipes/VBZ ./. A/DT number/NN of/IN curious/JJ and/CC authentic/JJ instances/NNS could/MD be/VB given/VBN of/IN various/JJ shades/NNS of/IN disposition/NN and/CC of/IN taste/NN ,/, and/CC likewise/RB of/IN the/DT oddest/JJS tricks/NNS ,/, associated/VBN with/IN certain/JJ frames/NNS of/IN mind/NN or/CC periods/NNS of/IN time/NN ,/, being/VBG inherited/VBN ./. 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I/PRP cannot/MD see/VB that/IN these/DT actions/NNS ,/, performed/VBN without/IN experience/NN by/IN the/DT young/JJ ,/, and/CC in/IN nearly/RB the/DT same/JJ manner/NN by/IN each/DT individual/JJ ,/, performed/VBN with/IN eager/JJ delight/NN by/IN each/DT breed/NN ,/, and/CC without/IN the/DT end/NN being/VBG known/VBN for/IN the/DT young/JJ pointer/NN can/MD no/DT more/JJR know/VB that/IN he/PRP points/NNS to/TO aid/NN his/PRP$ master/NN ,/, than/IN the/DT white/JJ butterfly/NN knows/VBZ why/WRB she/PRP lays/VBZ her/PRP$ eggs/NNS on/IN the/DT leaf/NN of/IN the/DT cabbage/NN I/PRP cannot/MD see/VB that/IN these/DT actions/NNS differ/VBP essentially/RB from/IN true/JJ instincts/NNS ./. If/IN we/PRP were/VBD to/TO behold/VB one/CD kind/NN of/IN wolf/NN ,/, when/WRB young/JJ and/CC without/IN any/DT training/NN ,/, as/IN soon/RB as/IN it/PRP scented/JJ its/PRP$ prey/NN ,/, stand/VB motionless/JJ like/IN a/DT statue/NN ,/, and/CC then/RB slowly/RB crawl/VB forward/RB with/IN a/DT peculiar/JJ gait/NN ;/: and/CC another/DT kind/NN of/IN wolf/NN rushing/VBG round/NN ,/, instead/RB of/IN at/IN ,/, a/DT herd/NN of/IN deer/NN ,/, and/CC driving/VBG them/PRP to/TO a/DT distant/JJ point/NN ,/, we/PRP should/MD assuredly/RB call/VB these/DT actions/NNS instinctive/JJ ./. Domestic/JJ instincts/NNS ,/, as/IN they/PRP may/MD be/VB called/VBN ,/, are/VBP certainly/RB far/RB less/JJR fixed/VBN than/IN natural/JJ instincts/NNS ;/: but/CC they/PRP have/VBP been/VBN acted/VBD on/IN by/IN far/RB less/JJR rigorous/JJ selection/NN ,/, and/CC have/VBP been/VBN transmitted/VBN for/IN an/DT incomparably/RB shorter/JJR period/NN ,/, under/IN less/JJR fixed/VBN conditions/NNS of/IN life/NN ./. How/WRB strongly/RB these/DT domestic/JJ instincts/NNS ,/, habits/NNS ,/, and/CC dispositions/NNS are/VBP inherited/VBN ,/, and/CC how/WRB curiously/RB they/PRP become/VB mingled/VBD ,/, is/VBZ well/RB shown/VBN when/WRB different/JJ breeds/NNS of/IN dogs/NNS are/VBP crossed/VBD ./. Thus/RB it/PRP is/VBZ known/VBN that/IN a/DT cross/VB with/IN a/DT bull/NN dog/NN has/VBZ affected/VBN for/IN many/JJ generations/NNS the/DT courage/NN and/CC obstinacy/NN of/IN greyhounds/NNS ;/: and/CC a/DT cross/VB with/IN a/DT greyhound/NN has/VBZ given/VBN to/TO a/DT whole/JJ family/NN of/IN shepherd/NN dogs/NNS a/DT tendency/NN to/TO hunt/NN hares/NNS ./. 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No/DT one/CD would/MD ever/RB have/VBP thought/VBD of/IN teaching/NN ,/, or/CC probably/RB could/MD have/VB taught/VBN ,/, the/DT tumbler/NN pigeon/NN to/TO tumble/NN ,/, an/DT action/NN which/WDT ,/, as/IN I/PRP have/VBP witnessed/VBN ,/, is/VBZ performed/VBN by/IN young/JJ birds/NNS ,/, that/IN have/VBP never/RB seen/VBN a/DT pigeon/NN tumble/NN ./. We/PRP may/MD believe/VB that/IN some/DT one/CD pigeon/NN showed/VBD a/DT slight/JJ tendency/NN to/TO this/DT strange/JJ habit/NN ,/, and/CC that/IN the/DT long/JJ continued/VBD selection/NN of/IN the/DT best/JJS individuals/NNS in/IN successive/JJ generations/NNS made/VBN tumblers/NNS what/WP they/PRP now/RB are/VBP ;/: and/CC near/IN Glasgow/NNP there/EX are/VBP house/NN tumblers/NNS ,/, as/IN I/PRP hear/VB from/IN Mr/NNP ./. Brent/NNP ,/, which/WDT cannot/MD fly/VB eighteen/CD inches/NNS high/JJ without/IN going/VBG head/NN over/IN heels/NNS ./. It/PRP may/MD be/VB doubted/VBD whether/IN any/DT one/CD would/MD have/VB thought/VBD of/IN training/NN a/DT dog/NN to/TO point/NN ,/, had/VBD not/RB some/DT one/CD dog/NN naturally/RB shown/VBN a/DT tendency/NN in/IN this/DT line/NN ;/: and/CC this/DT is/VBZ known/VBN occasionally/RB to/TO happen/VB ,/, as/IN I/PRP once/RB saw/VBD ,/, in/IN a/DT pure/JJ terrier/NN :/: the/DT act/NN of/IN pointing/VBG is/VBZ probably/RB ,/, as/IN many/JJ have/VBP thought/VBD ,/, only/RB the/DT exaggerated/VBN pause/NN of/IN an/DT animal/NN preparing/VBG to/TO spring/NN on/IN its/PRP$ prey/NN ./. When/WRB the/DT first/JJ tendency/NN to/TO point/NN was/VBD once/RB displayed/VBN ,/, methodical/JJ selection/NN and/CC the/DT inherited/VBN effects/NNS of/IN compulsory/JJ training/NN in/IN each/DT successive/JJ generation/NN would/MD soon/RB complete/JJ the/DT work/NN ;/: and/CC unconscious/JJ selection/NN is/VBZ still/RB in/IN progress/NN ,/, as/IN each/DT man/NN tries/VBZ to/TO procure/VB ,/, without/IN intending/VBG to/TO improve/VB the/DT breed/NN ,/, dogs/NNS which/WDT stand/VB and/CC hunt/NN best/JJS ./. On/IN the/DT other/JJ hand/NN ,/, habit/NN alone/RB in/IN some/DT cases/NNS has/VBZ sufficed/VBD ;/: hardly/RB any/DT animal/NN is/VBZ more/JJR difficult/JJ to/TO tame/JJ than/IN the/DT young/JJ of/IN the/DT wild/JJ rabbit/NN ;/: scarcely/RB any/DT animal/NN is/VBZ tamer/JJR than/IN the/DT young/JJ of/IN the/DT tame/JJ rabbit/NN ;/: but/CC I/PRP can/MD hardly/RB suppose/VBP that/IN domestic/JJ rabbits/NNS have/VBP often/RB been/VBN selected/VBN for/IN tameness/NN alone/RB ;/: so/RB that/IN we/PRP must/MD attribute/VB at/IN least/JJS the/DT greater/JJR part/NN of/IN the/DT inherited/VBN change/NN from/IN extreme/JJ wildness/NN to/TO extreme/JJ tameness/NN ,/, to/TO habit/NN and/CC long/JJ continued/VBD close/VB confinement/NN ./. 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All/DT wolves/NNS ,/, foxes/NNS ,/, jackals/NNS ,/, and/CC species/NN of/IN the/DT cat/NN genus/NN ,/, when/WRB kept/VBD tame/JJ ,/, are/VBP most/RBS eager/JJ to/TO attack/NN poultry/NN ,/, sheep/NN ,/, and/CC pigs/NNS ;/: and/CC this/DT tendency/NN has/VBZ been/VBN found/VBD incurable/JJ in/IN dogs/NNS which/WDT have/VBP been/VBN brought/VBN home/NN as/IN puppies/NNS from/IN countries/NNS such/JJ as/IN Tierra/NNP del/NNP Fuego/NNP and/CC Australia/NNP ,/, where/WRB the/DT savages/NNS do/VBP not/RB keep/VB these/DT domestic/JJ animals/NNS ./. How/WRB rarely/RB ,/, on/IN the/DT other/JJ hand/NN ,/, do/VBP our/PRP$ civilised/JJ dogs/NNS ,/, even/RB when/WRB quite/RB young/JJ ,/, require/VB to/TO be/VB taught/VBN not/RB to/TO attack/NN poultry/NN ,/, sheep/NN ,/, and/CC pigs!/NN No/DT doubt/NN they/PRP occasionally/RB do/VBP make/VB an/DT attack/NN ,/, and/CC are/VBP then/RB beaten/VBN ;/: and/CC if/IN not/RB cured/VBN ,/, they/PRP are/VBP destroyed/VBN ;/: so/RB that/IN habit/NN and/CC some/DT degree/NN of/IN selection/NN have/VBP probably/RB concurred/VBD in/IN civilising/VBG by/IN inheritance/NN our/PRP$ dogs/NNS ./. On/IN the/DT other/JJ hand/NN ,/, young/JJ chickens/NNS have/VBP lost/VBD ,/, wholly/RB by/IN habit/NN ,/, that/IN fear/NN of/IN the/DT dog/NN and/CC cat/NN which/WDT no/DT doubt/NN was/VBD originally/RB instinctive/JJ with/IN them/PRP ;/: for/IN I/PRP am/VBP informed/VBN by/IN Captain/NNP Hutton/NNP that/IN the/DT young/JJ chickens/NNS of/IN the/DT parent/NN stock/NN ,/, the/DT Gallus/NNP bankiva/NN ,/, when/WRB reared/VBD in/IN India/NNP under/IN a/DT hen/NN ,/, are/VBP at/IN first/JJ excessively/RB wild/JJ ./. So/RB it/PRP is/VBZ with/IN young/JJ pheasants/NNS reared/VBD in/IN England/NNP under/IN a/DT hen/NN ./. It/PRP is/VBZ not/RB that/IN chickens/NNS have/VBP lost/VBD all/DT fear/NN ,/, but/CC fear/NN only/RB of/IN dogs/NNS and/CC cats/NNS ,/, for/IN if/IN the/DT hen/NN gives/VBZ the/DT danger/NN chuckle/NN ,/, they/PRP will/MD run/VB (/( more/JJR especially/RB young/JJ turkeys/NNS )/SYM from/IN under/IN her/PRP$ ,/, and/CC conceal/VB themselves/PRP in/IN the/DT surrounding/VBG grass/NN or/CC thickets/NNS ;/: and/CC this/DT is/VBZ evidently/RB done/VBN for/IN the/DT instinctive/JJ purpose/NN of/IN allowing/VBG as/IN we/PRP see/VB in/IN wild/JJ ground/NN birds/NNS ,/, their/PRP$ mother/NN to/TO fly/VB away/RB ./. But/CC this/DT instinct/NN retained/VBN by/IN our/PRP$ chickens/NNS has/VBZ become/VB useless/JJ under/IN domestication/NN ,/, for/IN the/DT mother/NN hen/NN has/VBZ almost/RB lost/VBD by/IN disuse/NN the/DT power/NN of/IN flight/NN ./. Hence/RB ,/, we/PRP may/MD conclude/VB ,/, that/IN under/IN domestication/NN instincts/NNS have/VBP been/VBN acquired/VBN ,/, and/CC natural/JJ instincts/NNS have/VBP been/VBN lost/VBD ,/, partly/RB by/IN habit/NN ,/, and/CC partly/RB by/IN man/NN selecting/VBG and/CC accumulating/VBG ,/, during/IN successive/JJ generations/NNS ,/, peculiar/JJ mental/JJ habits/NNS and/CC actions/NNS ,/, which/WDT at/IN first/JJ appeared/VBD from/IN what/WP we/PRP must/MD in/IN our/PRP$ ignorance/NN call/VB an/DT accident/NN ./. In/IN some/DT cases/NNS compulsory/JJ habit/NN alone/RB has/VBZ sufficed/VBD to/TO produce/VB inherited/VBN mental/JJ changes/NNS ;/: in/IN other/JJ cases/NNS ,/, compulsory/JJ habit/NN has/VBZ done/VBN nothing/NN ,/, and/CC all/DT has/VBZ been/VBN the/DT result/NN of/IN selection/NN ,/, pursued/VBN both/DT methodically/RB and/CC unconsciously/RB :/: but/CC in/IN most/RBS cases/NNS habit/NN and/CC selection/NN have/VBP probably/RB concurred/VBD ./. Special/JJ Instincts/NNS We/PRP shall/MD ,/, perhaps/RB ,/, best/JJS understand/VB how/WRB instincts/NNS in/IN a/DT state/NN of/IN nature/NN have/VBP become/VB modified/VBN by/IN selection/NN by/IN considering/VBG a/DT few/JJ cases/NNS ./. I/PRP will/MD select/VB only/RB three/CD ,/, namely/RB ,/, the/DT instinct/NN which/WDT leads/VBZ the/DT cuckoo/NN to/TO lay/VBD her/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ;/: the/DT slave/NN making/VBG instinct/NN of/IN certain/JJ ants/NNS ;/: and/CC the/DT cell/NN making/VBG power/NN of/IN the/DT hive/NN bee/NN ./. These/DT two/CD latter/NN instincts/NNS have/VBP generally/RB and/CC justly/RB been/VBN ranked/VBD by/IN naturalists/NNS as/IN the/DT most/RBS wonderful/JJ of/IN all/DT known/VBN instincts/NNS ./. Instincts/NNS of/IN the/DT Cuckoo/NN ./. It/PRP is/VBZ supposed/VBN by/IN some/DT naturalists/NNS that/IN the/DT more/JJR immediate/JJ cause/NN of/IN the/DT instinct/NN of/IN the/DT cuckoo/NN is/VBZ ,/, that/IN she/PRP lays/VBZ her/PRP$ eggs/NNS ,/, not/RB daily/JJ ,/, but/CC at/IN intervals/NNS of/IN two/CD or/CC three/CD days/NNS ;/: so/RB that/IN ,/, if/IN she/PRP were/VBD to/TO make/VB her/PRP$ own/JJ nest/NN and/CC sit/VB on/IN her/PRP$ own/JJ eggs/NNS those/DT first/JJ laid/VBN would/MD have/VB to/TO be/VB left/VBN for/IN some/DT time/NN unincubated/JJ ,/, or/CC there/EX would/MD be/VB eggs/NNS and/CC young/JJ birds/NNS of/IN different/JJ ages/NNS in/IN the/DT same/JJ nest/NN ./. If/IN this/DT were/VBD the/DT case/NN ,/, the/DT process/NN of/IN laying/VBG and/CC hatching/NN might/MD be/VB inconveniently/RB long/JJ ,/, more/JJR especially/RB as/IN she/PRP migrates/VBZ at/IN a/DT very/RB early/JJ period/NN ;/: and/CC the/DT first/JJ hatched/VBN young/JJ would/MD probably/RB have/VBP to/TO be/VB fed/VBN by/IN the/DT male/JJ alone/RB ./. But/CC the/DT American/NNP cuckoo/NN is/VBZ in/IN this/DT predicament/NN ;/: for/IN she/PRP makes/VBZ her/PRP$ own/JJ nest/NN ,/, and/CC has/VBZ eggs/NNS and/CC young/JJ successively/RB hatched/VBN ,/, all/DT at/IN the/DT same/JJ time/NN ./. It/PRP has/VBZ been/VBN both/DT asserted/VBD and/CC denied/VBN that/IN the/DT American/NNP cuckoo/NN occasionally/RB lays/VBZ her/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ;/: but/CC I/PRP have/VBP lately/RB heard/VBN from/IN Dr/NNP ./. Merrell/NNP ,/, of/IN Iowa/NNP ,/, that/IN he/PRP once/RB found/VBD in/IN Illinois/NNP a/DT young/JJ cuckoo/NN together/RB with/IN a/DT young/JJ jay/NN in/IN the/DT nest/NN of/IN a/DT blue/JJ jay/NN (/( Garrulus/NNP cristatus/JJ )/SYM ;/: and/CC as/IN both/DT were/VBD nearly/RB full/JJ feathered/JJ ,/, there/EX could/MD be/VB no/DT mistake/NN in/IN their/PRP$ identification/NN ./. I/PRP could/MD also/RB give/VB several/JJ instances/NNS of/IN various/JJ birds/NNS which/WDT have/VBP been/VBN known/VBN occasionally/RB to/TO lay/VBD their/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ./. Now/RB let/VB us/PRP suppose/VBP that/IN the/DT ancient/JJ progenitor/NN of/IN our/PRP$ European/JJ cuckoo/NN had/VBD the/DT habits/NNS of/IN the/DT American/NNP cuckoo/NN ,/, and/CC that/IN she/PRP occasionally/RB laid/VBN an/DT egg/NN in/IN another/DT bird's/NNS nest/NN ./. If/IN the/DT old/JJ bird/NN profited/VBD by/IN this/DT occasional/JJ habit/NN through/IN being/VBG enabled/VBD to/TO migrate/VB earlier/RBR or/CC through/IN any/DT other/JJ cause/NN ;/: or/CC if/IN the/DT young/JJ were/VBD made/VBN more/JJR vigorous/JJ by/IN advantage/NN being/VBG taken/VBN of/IN the/DT mistaken/VBN instinct/NN of/IN another/DT species/NN than/IN when/WRB reared/VBD by/IN their/PRP$ own/JJ mother/NN ,/, encumbered/VBN as/IN she/PRP could/MD hardly/RB fail/VB to/TO be/VB by/IN having/VBG eggs/NNS and/CC young/JJ of/IN different/JJ ages/NNS at/IN the/DT same/JJ time/NN ;/: then/RB the/DT old/JJ birds/NNS or/CC the/DT fostered/VBN young/JJ would/MD gain/NN an/DT advantage/NN ./. And/CC analogy/NN would/MD lead/VB us/PRP to/TO believe/VB ,/, that/IN the/DT young/JJ thus/RB reared/VBD would/MD be/VB apt/JJ to/TO follow/VB by/IN inheritance/NN the/DT occasional/JJ and/CC aberrant/JJ habit/NN of/IN their/PRP$ mother/NN ,/, and/CC in/IN their/PRP$ turn/VB would/MD be/VB apt/JJ to/TO lay/VBD their/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ,/, and/CC thus/RB be/VB more/JJR successful/JJ in/IN rearing/VBG their/PRP$ young/JJ ./. By/IN a/DT continued/VBD process/NN of/IN this/DT nature/NN ,/, I/PRP believe/VBP that/IN the/DT strange/JJ instinct/NN of/IN our/PRP$ cuckoo/NN has/VBZ been/VBN generated/VBN ./. It/PRP has/VBZ ,/, also/RB ,/, recently/RB been/VBN ascertained/VBN on/IN sufficient/JJ evidence/NN ,/, by/IN Adolf/NNP Muller/NNP ,/, that/IN the/DT cuckoo/NN occasionally/RB lays/VBZ her/PRP$ eggs/NNS on/IN the/DT bare/JJ ground/NN ,/, sits/VBZ on/IN them/PRP ,/, and/CC feeds/VBZ her/PRP$ young/JJ ./. This/DT rare/JJ event/NN is/VBZ probably/RB a/DT case/NN of/IN reversion/NN to/TO the/DT long/JJ lost/VBD ,/, aboriginal/JJ instinct/NN of/IN nidification/NN ./. It/PRP has/VBZ been/VBN objected/VBD that/IN I/PRP have/VBP not/RB noticed/VBD other/JJ related/VBN instincts/NNS and/CC adaptations/NNS of/IN structure/NN in/IN the/DT cuckoo/NN ,/, which/WDT are/VBP spoken/VBN of/IN as/IN necessarily/RB co/NN ordinated/VBN ./. But/CC in/IN all/DT cases/NNS ,/, speculation/NN on/IN an/DT instinct/NN known/VBN to/TO us/PRP only/RB in/IN a/DT single/JJ species/NN ,/, is/VBZ useless/JJ ,/, for/IN we/PRP have/VBP hitherto/RB had/VBD no/DT facts/NNS to/TO guide/NN us/PRP ./. Until/IN recently/RB the/DT instincts/NNS of/IN the/DT European/JJ and/CC of/IN the/DT nonparasitic/JJ American/NNP cuckoo/NN alone/RB were/VBD known/VBN ./. now/RB ,/, owing/JJ to/TO Mr/NNP ./. Ramsay's/NNP observations/NNS ,/, we/PRP have/VBP learnt/NN something/NN about/IN three/CD Australian/JJ species/NN ,/, which/WDT lay/VBD their/PRP$ eggs/NNS in/IN other/JJ birds'/NN nests/NNS ./. The/DT chief/JJ points/NNS to/TO be/VB referred/VBN to/TO are/VBP three/CD :/: first/JJ ,/, that/IN the/DT common/JJ cuckoo/NN ,/, with/IN rare/JJ exceptions/NNS ,/, lays/VBZ only/RB one/CD egg/NN in/IN a/DT nest/NN ,/, so/RB that/IN the/DT large/JJ and/CC voracious/JJ young/JJ bird/NN receives/VBZ ample/JJ food/NN ./. Secondly/RB ,/, that/IN the/DT eggs/NNS are/VBP remarkably/RB small/JJ ,/, not/RB exceeding/VBG those/DT of/IN the/DT skylark/NN ,/, a/DT bird/NN about/IN one/CD fourth/JJ as/IN large/JJ as/IN the/DT cuckoo/NN ./. That/DT the/DT small/JJ size/NN of/IN the/DT egg/NN is/VBZ a/DT real/JJ cause/NN of/IN adaptation/NN we/PRP may/MD infer/VB from/IN the/DT fact/NN of/IN the/DT non/FW parasitic/JJ American/NNP cuckoo/NN laying/VBG full/JJ sized/VBD eggs/NNS ./. Thirdly/RB ,/, that/IN the/DT young/JJ cuckoo/NN ,/, soon/RB after/IN birth/NN ,/, has/VBZ the/DT instinct/NN ,/, the/DT strength/NN ,/, and/CC a/DT properly/RB shaped/VBN back/RB for/IN ejecting/VBG its/PRP$ foster/VB brothers/NNS ,/, which/WDT then/RB perish/VB from/IN cold/JJ and/CC hunger/NN ./. This/DT has/VBZ been/VBN boldly/RB called/VBN a/DT beneficent/NN arrangement/NN ,/, in/IN order/NN that/IN the/DT young/JJ cuckoo/NN may/MD get/VB sufficient/JJ food/NN ,/, and/CC that/IN its/PRP$ foster/VB brothers/NNS may/MD perish/VB before/IN they/PRP had/VBD acquired/VBN much/JJ feeling!/NN Turning/VBG now/RB to/TO the/DT Australian/JJ species/NN ;/: though/IN these/DT birds/NNS generally/RB lay/VBD only/RB one/CD egg/NN in/IN a/DT nest/NN ,/, it/PRP is/VBZ not/RB rare/JJ to/TO find/VB two/CD or/CC even/RB three/CD eggs/NNS in/IN the/DT same/JJ nest/NN ./. In/IN the/DT bronze/NN cuckoo/NN the/DT eggs/NNS vary/VBP greatly/RB in/IN size/NN ,/, from/IN eight/CD to/TO ten/CD times/NNS in/IN length/NN ./. Now/RB if/IN it/PRP had/VBD been/VBN of/IN an/DT advantage/NN to/TO this/DT species/NN to/TO have/VB laid/VBN eggs/NNS even/RB smaller/JJR than/IN those/DT now/RB laid/VBN ,/, so/RB as/IN to/TO have/VB deceived/VBN certain/JJ foster/VB parents/NNS ,/, or/CC ,/, as/IN is/VBZ more/JJR probable/JJ ,/, to/TO have/VB been/VBN hatched/VBN within/IN a/DT shorter/JJR period/NN (/( for/IN it/PRP is/VBZ asserted/VBN that/IN there/EX is/VBZ a/DT relation/NN between/IN the/DT size/NN of/IN eggs/NNS and/CC the/DT period/NN of/IN their/PRP$ incubation/NN )/SYM ,/, then/RB there/EX is/VBZ no/DT difficulty/NN in/IN believing/VBG that/IN a/DT race/NN or/CC species/NN might/MD have/VB been/VBN formed/VBN which/WDT would/MD have/VB laid/VBN smaller/JJR and/CC smaller/JJR eggs/NNS ;/: for/IN these/DT would/MD have/VB been/VBN more/JJR safely/RB hatched/VBN and/CC reared/VBD ./. Mr/NNP ./. Ramsay/NNP remarks/NNS that/IN two/CD of/IN the/DT Australian/JJ cuckoos/NNS ,/, when/WRB they/PRP lay/VBD their/PRP$ eggs/NNS in/IN an/DT open/JJ nest/NN ,/, manifest/JJ a/DT decided/VBD preference/NN for/IN nests/NNS containing/VBG eggs/NNS similar/JJ in/IN colour/NN to/TO their/PRP$ own/JJ ./. The/DT European/JJ species/NN apparently/RB manifests/NNS some/DT tendency/NN towards/IN a/DT similar/JJ instinct/NN ,/, but/CC not/RB rarely/RB departs/VBZ from/IN it/PRP ,/, as/IN is/VBZ shown/VBN by/IN her/PRP$ laying/VBG her/PRP$ dull/JJ and/CC pale/JJ coloured/JJ eggs/NNS in/IN the/DT nest/NN of/IN the/DT Hedge/NNP warbler/NN with/IN bright/JJ greenish/JJ blue/JJ eggs/NNS ./. Had/VBD our/PRP$ cuckoo/NN invariably/RB displayed/VBN the/DT above/IN instinct/NN ,/, it/PRP would/MD assuredly/RB have/VBP been/VBN added/VBD to/TO those/DT which/WDT it/PRP is/VBZ assumed/VBN must/MD all/DT have/VBP been/VBN acquired/VBN together/RB ./. The/DT eggs/NNS of/IN the/DT Australian/JJ bronze/NN cuckoo/NN vary/VBP ,/, according/VBG to/TO Mr/NNP ./. Ramsay/NNP ,/, to/TO an/DT extraordinary/JJ degree/NN in/IN colour/NN ;/: so/RB that/IN in/IN this/DT respect/NN ,/, as/IN well/RB as/IN in/IN size/NN ,/, natural/JJ selection/NN might/MD have/VB secured/VBN and/CC fixed/VBN any/DT advantageous/JJ variation/NN ./. In/IN the/DT case/NN of/IN the/DT European/JJ cuckoo/NN ,/, the/DT offspring/NN of/IN the/DT foster/VB parents/NNS are/VBP commonly/RB ejected/VBN from/IN the/DT nest/NN within/IN three/CD days/NNS after/IN the/DT cuckoo/NN is/VBZ hatched/VBN ;/: and/CC as/IN the/DT latter/NN at/IN this/DT age/NN is/VBZ in/IN a/DT most/RBS helpless/JJ condition/NN ,/, Mr/NNP ./. Gould/NNP was/VBD formerly/RB inclined/VBN to/TO believe/VB that/IN the/DT act/NN of/IN ejection/NN was/VBD performed/VBN by/IN the/DT foster/VB parents/NNS themselves/PRP ./. But/CC he/PRP has/VBZ now/RB received/VBD a/DT trustworthy/JJ account/NN of/IN a/DT young/JJ cuckoo/NN which/WDT was/VBD actually/RB seen/VBN ,/, whilst/NN still/RB blind/JJ and/CC not/RB able/JJ even/RB to/TO hold/VB up/IN its/PRP$ own/JJ head/NN ,/, in/IN the/DT act/NN of/IN ejecting/VBG its/PRP$ foster/VB brothers/NNS ./. One/CD of/IN these/DT was/VBD replaced/VBN in/IN the/DT nest/NN by/IN the/DT observer/NN ,/, and/CC was/VBD again/RB thrown/VBN out/IN ./. With/IN respect/NN to/TO the/DT means/VBZ by/IN which/WDT this/DT strange/JJ and/CC odious/JJ instinct/NN was/VBD acquired/VBN ,/, if/IN it/PRP were/VBD of/IN great/JJ importance/NN for/IN the/DT young/JJ cuckoo/NN ,/, as/IN is/VBZ probably/RB the/DT case/NN ,/, to/TO receive/VB as/IN much/JJ food/NN as/IN possible/JJ soon/RB after/IN birth/NN ,/, I/PRP can/MD see/VB no/DT special/JJ difficulty/NN in/IN its/PRP$ having/VBG gradually/RB acquired/VBN ,/, during/IN successive/JJ generations/NNS ,/, the/DT blind/JJ desire/NN ,/, the/DT strength/NN ,/, and/CC structure/NN necessary/JJ for/IN the/DT work/NN of/IN ejection/NN ;/: for/IN those/DT young/JJ cuckoos/NNS which/WDT had/VBD such/JJ habits/NNS and/CC structure/NN best/JJS developed/VBN would/MD be/VB the/DT most/RBS securely/RB reared/VBD ./. The/DT first/JJ step/NN towards/IN the/DT acquisition/NN of/IN the/DT proper/JJ instinct/NN might/MD have/VB been/VBN more/JJR unintentional/JJ restlessness/NN on/IN the/DT part/NN of/IN the/DT young/JJ bird/NN ,/, when/WRB somewhat/RB advanced/VBD in/IN age/NN and/CC strength/NN ;/: the/DT habit/NN having/VBG been/VBN afterwards/RB improved/VBN ,/, and/CC transmitted/VBN to/TO an/DT earlier/RBR age/NN ./. I/PRP can/MD see/VB no/DT more/JJR difficulty/NN in/IN this/DT ,/, than/IN in/IN the/DT unhatched/JJ young/JJ of/IN other/JJ birds/NNS acquiring/VBG the/DT instinct/NN to/TO break/VB through/IN their/PRP$ own/JJ shells/NNS ;/: or/CC than/IN in/IN young/JJ snakes/NNS acquiring/VBG in/IN their/PRP$ upper/JJ jaws/NNS ,/, as/IN Owen/NNP has/VBZ remarked/VBN ,/, a/DT transitory/JJ sharp/JJ tooth/NN for/IN cutting/VBG through/IN the/DT tough/JJ egg/NN shell/NN ./. For/IN if/IN each/DT part/NN is/VBZ liable/JJ to/TO individual/JJ variations/NNS at/IN all/DT ages/NNS ,/, and/CC the/DT variations/NNS tend/VBP to/TO be/VB inherited/VBN at/IN a/DT corresponding/JJ or/CC earlier/RBR age/NN ,/, propositions/NNS which/WDT cannot/MD be/VB disputed/VBN ,/, then/RB the/DT instincts/NNS and/CC structure/NN of/IN the/DT young/JJ could/MD be/VB slowly/RB modified/VBN as/IN surely/RB as/IN those/DT of/IN the/DT adult/NN ;/: and/CC both/DT cases/NNS must/MD stand/VB or/CC fall/NN together/RB with/IN the/DT whole/JJ theory/NN of/IN natural/JJ selection/NN ./. Some/DT species/NN of/IN Molothrus/NNP ,/, a/DT widely/RB distinct/JJ genus/NN of/IN American/NNP birds/NNS ,/, allied/VBN to/TO our/PRP$ starlings/NNS ,/, have/VBP parasitic/JJ habits/NNS like/IN those/DT of/IN the/DT cuckoo/NN ;/: and/CC the/DT species/NN present/JJ an/DT interesting/JJ gradation/NN in/IN the/DT perfection/NN of/IN their/PRP$ instincts/NNS ./. The/DT sexes/NNS of/IN Molothrus/NNP badius/JJ are/VBP stated/VBN by/IN an/DT excellent/JJ observer/NN ,/, Mr/NNP ./. Hudson/NNP ,/, sometimes/RB to/TO live/VB promiscuously/RB together/RB in/IN flocks/NNS ,/, and/CC sometimes/RB to/TO pair/NN ./. They/PRP either/DT build/VB a/DT nest/NN of/IN their/PRP$ own/JJ ,/, or/CC seize/VB on/IN one/CD belonging/VBG to/TO some/DT other/JJ bird/NN ,/, occasionally/RB throwing/VBG out/IN the/DT nestlings/NNS of/IN the/DT stranger/NN ./. They/PRP either/DT lay/VBD their/PRP$ eggs/NNS in/IN the/DT nest/NN thus/RB appropriated/VBN ,/, or/CC oddly/RB enough/RB build/VB one/CD for/IN themselves/PRP on/IN the/DT top/JJ of/IN it/PRP ./. They/PRP usually/RB sit/VB on/IN their/PRP$ own/JJ eggs/NNS and/CC rear/JJ their/PRP$ own/JJ young/JJ ;/: but/CC Mr/NNP ./. Hudson/NNP says/VBZ it/PRP is/VBZ probable/JJ that/IN they/PRP are/VBP occasionally/RB parasitic/JJ ,/, for/IN he/PRP has/VBZ seen/VBN the/DT young/JJ of/IN this/DT species/NN following/VBG old/JJ birds/NNS of/IN a/DT distinct/JJ kind/NN and/CC clamouring/VBG to/TO be/VB fed/VBN by/IN them/PRP ./. The/DT parasitic/JJ habits/NNS of/IN another/DT species/NN of/IN Molothrus/NNP ,/, the/DT M/NNP ./. bonariensis/NN ,/, are/VBP much/JJ more/JJR highly/RB developed/VBN than/IN those/DT of/IN the/DT last/JJ ,/, but/CC are/VBP still/RB far/RB from/IN perfect/JJ ./. This/DT bird/NN ,/, as/IN far/RB as/IN it/PRP is/VBZ known/VBN ,/, invariably/RB lays/VBZ its/PRP$ eggs/NNS in/IN the/DT nests/NNS of/IN strangers/NNS ;/: but/CC it/PRP is/VBZ remarkable/JJ that/IN several/JJ together/RB sometimes/RB commence/VB to/TO build/VB an/DT irregular/JJ untidy/JJ nest/NN of/IN their/PRP$ own/JJ ,/, placed/VBN in/IN singularly/RB ill/JJ adapted/VBN situations/NNS ,/, as/IN on/IN the/DT leaves/VBZ of/IN a/DT large/JJ thistle/NN ./. They/PRP never/RB ,/, however/RB ,/, as/IN far/RB as/IN Mr/NNP ./. Hudson/NNP has/VBZ ascertained/VBN ,/, complete/JJ a/DT nest/NN for/IN themselves/PRP ./. They/PRP often/RB lay/VBD so/RB many/JJ eggs/NNS from/IN fifteen/CD to/TO twenty/CD in/IN the/DT same/JJ foster/VB nest/NN ,/, that/IN few/JJ or/CC none/NN can/MD possibly/RB be/VB hatched/VBN ./. They/PRP have/VBP ,/, moreover/RB ,/, the/DT extraordinary/JJ habit/NN of/IN pecking/VBG holes/NNS in/IN the/DT eggs/NNS ,/, whether/IN of/IN their/PRP$ own/JJ species/NN or/CC of/IN their/PRP$ foster/VB parents/NNS ,/, which/WDT they/PRP find/VB in/IN the/DT appropriated/VBN nests/NNS ./. They/PRP drop/NN also/RB many/JJ eggs/NNS on/IN the/DT bare/JJ ground/NN ,/, which/WDT are/VBP thus/RB wasted/VBN ./. A/DT third/JJ species/NN ,/, the/DT M/NNP ./. pecoris/NN of/IN North/NNP America/NNP ,/, has/VBZ acquired/VBN instincts/NNS as/IN perfect/JJ as/IN those/DT of/IN the/DT cuckoo/NN ,/, for/IN it/PRP never/RB lays/VBZ more/JJR than/IN one/CD egg/NN in/IN a/DT foster/VB nest/NN ,/, so/RB that/IN the/DT young/JJ bird/NN is/VBZ securely/RB reared/VBD ./. Mr/NNP ./. Hudson/NNP is/VBZ a/DT strong/JJ disbeliever/NN in/IN evolution/NN ,/, but/CC he/PRP appears/VBZ to/TO have/VB been/VBN so/RB much/JJ struck/VBD by/IN the/DT imperfect/JJ instincts/NNS of/IN the/DT Molothrus/NNP bonariensis/NN that/IN he/PRP quotes/NNS my/PRP$ words/NNS ,/, and/CC asks/VBZ ,/, "/" Must/MD we/PRP consider/VB these/DT habits/NNS ,/, not/RB as/IN especially/RB endowed/VBN or/CC created/VBN instincts/NNS ,/, but/CC as/IN small/JJ consequences/NNS of/IN one/CD general/JJ law/NN ,/, namely/RB ,/, transition/NN ?/. "/" Various/JJ birds/NNS ,/, as/IN has/VBZ already/RB been/VBN remarked/VBD ,/, occasionally/RB lay/VBD their/PRP$ eggs/NNS in/IN the/DT nest/NN of/IN other/JJ birds/NNS ./. This/DT habit/NN is/VBZ not/RB very/RB uncommon/JJ with/IN the/DT Gallinaceae/NNP ,/, and/CC throws/VBZ some/DT light/NN on/IN the/DT singular/JJ instinct/NN of/IN the/DT ostrich/JJ ./. In/IN this/DT family/NN several/JJ hen/NN birds/NNS unite/VB and/CC lay/VBD first/JJ a/DT few/JJ eggs/NNS in/IN one/CD nest/NN and/CC then/RB in/IN another/DT ;/: and/CC these/DT are/VBP hatched/VBN by/IN the/DT males/NNS ./. This/DT instinct/NN may/MD probably/RB be/VB accounted/VBD for/IN by/IN the/DT fact/NN of/IN the/DT hens/NNS laying/VBG a/DT large/JJ number/NN of/IN eggs/NNS ,/, but/CC ,/, as/IN with/IN the/DT cuckoo/NN ,/, at/IN intervals/NNS of/IN two/CD or/CC three/CD days/NNS ./. The/DT instinct/NN ,/, however/RB ,/, of/IN the/DT American/NNP ostrich/JJ ,/, as/IN in/IN the/DT case/NN of/IN the/DT Molothrus/NNP bonariensis/NN ,/, has/VBZ not/RB as/IN yet/RB been/VBN perfected/VBN ;/: for/IN a/DT surprising/JJ number/NN of/IN eggs/NNS lie/VB strewed/VBN over/IN the/DT plains/NNS ,/, so/RB that/IN in/IN one/CD day's/NNS hunting/NN I/PRP picked/VBD up/IN no/DT less/JJR than/IN twenty/CD lost/VBD and/CC wasted/VBN eggs/NNS ./. Many/JJ bees/NNS are/VBP parasitic/JJ ,/, and/CC regularly/RB lay/VBD their/PRP$ eggs/NNS in/IN the/DT nests/NNS of/IN other/JJ kinds/NNS of/IN bees/NNS ./. This/DT case/NN is/VBZ more/JJR remarkable/JJ than/IN that/IN of/IN the/DT cuckoo/NN ;/: for/IN these/DT bees/NNS have/VBP not/RB only/RB had/VBD their/PRP$ instincts/NNS but/CC their/PRP$ structure/NN modified/VBN in/IN accordance/NN with/IN their/PRP$ parasitic/JJ habits/NNS ;/: for/IN they/PRP do/VBP not/RB possess/VBP the/DT pollen/NN collecting/VBG apparatus/NN which/WDT would/MD have/VB been/VBN indispensable/JJ if/IN they/PRP had/VBD stored/VBN up/IN food/NN for/IN their/PRP$ own/JJ young/JJ ./. Some/DT species/NN of/IN Sphegidea/NNP (/( wasp/NN like/IN insects/NNS )/SYM are/VBP likewise/RB parasitic/JJ ;/: and/CC M/NNP ./. Fabre/NNP has/VBZ lately/RB shown/VBN good/JJ reason/NN for/IN believing/VBG that/IN ,/, although/IN the/DT Tachytes/NNP nigra/NN generally/RB makes/VBZ its/PRP$ own/JJ burrow/NN and/CC stores/NNS it/PRP with/IN paralysed/VBN prey/NN for/IN its/PRP$ own/JJ larvae/NNS ,/, yet/RB that/IN ,/, when/WRB this/DT insect/NN finds/VBZ a/DT burrow/NN already/RB made/VBN and/CC stored/VBN by/IN another/DT species/NN ,/, it/PRP takes/VBZ advantage/NN of/IN the/DT prize/NN and/CC becomes/VBZ for/IN the/DT occasion/NN parasitic/JJ ./. In/IN this/DT case/NN ,/, as/IN with/IN that/IN of/IN the/DT Molothrus/NNP or/CC cuckoo/NN ,/, I/PRP can/MD see/VB no/DT difficulty/NN in/IN natural/JJ selection/NN making/VBG an/DT occasional/JJ habit/NN permanent/JJ ,/, if/IN of/IN advantage/NN to/TO the/DT species/NN ,/, and/CC if/IN the/DT insect/NN whose/WP$ nest/NN and/CC stored/VBN food/NN are/VBP feloniously/RB appropriated/VBN ,/, be/VB not/RB thus/RB exterminated/VBN ./. Slave/NNP making/VBG instinct/NN ./. This/DT remarkable/JJ instinct/NN was/VBD first/JJ discovered/VBN in/IN the/DT Formica/NNP (/( Polyerges/NNP )/SYM rufescens/NNS by/IN Pierre/NNP Huber/NNP ,/, a/DT better/JJR observer/NN even/RB than/IN his/PRP$ celebrated/VBD father/NN ./. This/DT ant/NN is/VBZ absolutely/RB dependent/JJ on/IN its/PRP$ slaves/NNS ;/: without/IN their/PRP$ aid/NN ,/, the/DT species/NN would/MD certainly/RB become/VB extinct/JJ in/IN a/DT single/JJ year/NN ./. The/DT males/NNS and/CC fertile/JJ female/JJ do/VBP no/DT work/NN of/IN any/DT kind/NN ,/, and/CC the/DT workers/NNS or/CC sterile/JJ females/NNS ,/, though/IN most/RBS energetic/JJ and/CC courageous/JJ in/IN capturing/VBG slaves/NNS ,/, do/VBP no/DT other/JJ work/NN ./. They/PRP are/VBP incapable/JJ of/IN making/VBG their/PRP$ own/JJ nests/NNS ,/, or/CC of/IN feeding/VBG their/PRP$ own/JJ larvae/NNS ./. When/WRB the/DT old/JJ nest/NN is/VBZ found/VBN inconvenient/JJ ,/, and/CC they/PRP have/VBP to/TO migrate/VB ,/, it/PRP is/VBZ the/DT slaves/NNS which/WDT determine/VB the/DT migration/NN ,/, and/CC actually/RB carry/VB their/PRP$ masters/NNS in/IN their/PRP$ jaws/NNS ./. So/RB utterly/RB helpless/JJ are/VBP the/DT masters/NNS ,/, that/IN when/WRB Huber/NNP shut/VBN up/IN thirty/CD of/IN them/PRP without/IN a/DT slave/NN ,/, but/CC with/IN plenty/NN of/IN the/DT food/NN which/WDT they/PRP like/IN best/JJS ,/, and/CC with/IN their/PRP$ own/JJ larvae/NNS and/CC pupae/NN to/TO stimulate/VB them/PRP to/TO work/NN ,/, they/PRP did/VBD nothing/NN ;/: they/PRP could/MD not/RB even/RB feed/NN themselves/PRP ,/, and/CC many/JJ perished/VBD of/IN hunger/NN ./. Huber/NNP then/RB introduced/VBN a/DT single/JJ slave/NN (/( F/NN ./. fusca/NN )/SYM ,/, and/CC she/PRP instantly/RB set/VBN to/TO work/NN ,/, fed/VBN and/CC saved/VBN the/DT survivors/NNS ;/: made/VBN some/DT cells/NNS and/CC tended/VBD the/DT larvae/NNS ,/, and/CC put/VB all/DT to/TO rights/NNS ./. What/WP can/MD be/VB more/JJR extraordinary/JJ than/IN these/DT well/RB ascertained/VBN facts/NNS ?/. If/IN we/PRP had/VBD not/RB known/VBN of/IN any/DT other/JJ slave/NN making/VBG ant/NN ,/, it/PRP would/MD have/VB been/VBN hopeless/JJ to/TO speculate/VB how/WRB so/RB wonderful/JJ an/DT instinct/NN could/MD have/VB been/VBN perfected/VBN ./. Another/DT species/NN ,/, Formica/NNP sanguinea/NN ,/, was/VBD likewise/RB first/JJ discovered/VBN by/IN P/NN ./. Huber/NNP to/TO be/VB a/DT slave/NN making/VBG ant/NN ./. This/DT species/NN is/VBZ found/VBN in/IN the/DT southern/JJ parts/NNS of/IN England/NNP ,/, and/CC its/PRP$ habits/NNS have/VBP been/VBN attended/VBD to/TO by/IN Mr/NNP ./. F/NN ./. Smith/NNP ,/, of/IN the/DT British/JJ Museum/NNP ,/, to/TO whom/WP I/PRP am/VBP much/JJ indebted/JJ for/IN information/NN on/IN this/DT and/CC other/JJ subjects/NNS ./. Although/IN fully/RB trusting/JJ to/TO the/DT statements/NNS of/IN Huber/NNP and/CC Mr/NNP ./. Smith/NNP ,/, I/PRP tried/VBD to/TO approach/NN the/DT subject/NN in/IN a/DT sceptical/JJ frame/NN of/IN mind/NN ,/, as/IN any/DT one/CD may/MD well/RB be/VB excused/VBN for/IN doubting/VBG the/DT existence/NN of/IN so/RB extraordinary/JJ an/DT instinct/NN as/IN that/IN of/IN making/VBG slaves/NNS ./. Hence/RB ,/, I/PRP will/MD give/VB the/DT observations/NNS which/WDT I/PRP made/VBN in/IN some/DT little/JJ detail/NN ./. I/PRP opened/VBD fourteen/CD nests/NNS of/IN F/NN ./. sanguinea/NN ,/, and/CC found/VBD a/DT few/JJ slaves/NNS in/IN all/DT ./. Males/NNPS and/CC fertile/JJ females/NNS of/IN the/DT slave/NN species/NN (/( F/NN ./. fusca/NN )/SYM are/VBP found/VBD only/RB in/IN their/PRP$ own/JJ proper/JJ communities/NNS ,/, and/CC have/VBP never/RB been/VBN observed/VBN in/IN the/DT nests/NNS of/IN F/NN ./. sanguinea/NN ./. The/DT slaves/NNS are/VBP black/JJ and/CC not/RB above/IN half/NN the/DT size/NN of/IN their/PRP$ red/JJ masters/NNS ,/, so/RB that/IN the/DT contrast/NN in/IN their/PRP$ appearance/NN is/VBZ great/JJ ./. When/WRB the/DT nest/NN is/VBZ slightly/RB disturbed/VBN ,/, the/DT slaves/NNS occasionally/RB come/VB out/IN ,/, and/CC like/IN their/PRP$ masters/NNS are/VBP much/JJ agitated/VBD and/CC defend/VB the/DT nest/NN :/: when/WRB the/DT nest/NN is/VBZ much/JJ disturbed/VBN ,/, and/CC the/DT larvae/NNS and/CC pupae/NN are/VBP exposed/VBN ,/, the/DT slaves/NNS work/NN energetically/RB together/RB with/IN their/PRP$ masters/NNS in/IN carrying/VBG them/PRP away/RB to/TO a/DT place/NN of/IN safety/NN ./. Hence/RB ,/, it/PRP is/VBZ clear/JJ ,/, that/IN the/DT slaves/NNS feel/VB quite/RB at/IN home/NN ./. During/IN the/DT months/NNS of/IN June/NNP and/CC July/NNP ,/, on/IN three/CD successive/JJ years/NNS ,/, I/PRP watched/VBD for/IN many/JJ hours/NNS several/JJ nests/NNS in/IN Surrey/NNP and/CC Sussex/NNP ,/, and/CC never/RB saw/VBD a/DT slave/NN either/DT leave/VB or/CC enter/VB a/DT nest/NN ./. As/IN ,/, during/IN these/DT months/NNS ,/, the/DT slaves/NNS are/VBP very/RB few/JJ in/IN number/NN ,/, I/PRP thought/VBD that/IN they/PRP might/MD behave/VB differently/RB when/WRB more/JJR numerous/JJ ;/: but/CC Mr/NNP ./. Smith/NNP informs/VBZ me/PRP that/IN he/PRP has/VBZ watched/VBN the/DT nests/NNS at/IN various/JJ hours/NNS during/IN May/NNP ,/, June/NNP ,/, and/CC August/NNP ,/, both/DT in/IN Surrey/NNP and/CC Hampshire/NNP ,/, and/CC has/VBZ never/RB seen/VBN the/DT slaves/NNS ,/, though/IN present/JJ in/IN large/JJ numbers/NNS in/IN August/NNP ,/, either/DT leave/VB or/CC enter/VB the/DT nest/NN ./. Hence/RB he/PRP considers/VBZ them/PRP as/IN strictly/RB household/NN slaves/NNS ./. The/DT masters/NNS ,/, on/IN the/DT other/JJ hand/NN ,/, may/MD be/VB constantly/RB seen/VBN bringing/VBG in/IN materials/NNS for/IN the/DT nest/NN ,/, and/CC food/NN of/IN all/DT kinds/NNS ./. 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According/VBG to/TO Huber/NNP ,/, who/WP had/VBD ample/JJ opportunities/NNS for/IN observation/NN ,/, the/DT slaves/NNS in/IN Switzerland/NNP habitually/RB work/NN with/IN their/PRP$ masters/NNS in/IN making/VBG the/DT nest/NN ,/, and/CC they/PRP alone/RB open/JJ and/CC close/VB the/DT doors/NNS in/IN the/DT morning/NN and/CC evening/NN ;/: and/CC ,/, as/IN Huber/NNP expressly/RB states/NNS ,/, their/PRP$ principal/JJ office/NN is/VBZ to/TO search/NN for/IN aphides/NNS ./. This/DT difference/NN in/IN the/DT usual/JJ habits/NNS of/IN the/DT masters/NNS and/CC slaves/NNS in/IN the/DT two/CD countries/NNS ,/, probably/RB depends/VBZ merely/RB on/IN the/DT slaves/NNS being/VBG captured/VBN in/IN greater/JJR numbers/NNS in/IN Switzerland/NNP than/IN in/IN England/NNP ./. One/CD day/NN I/PRP fortunately/RB witnessed/VBN a/DT migration/NN of/IN F/NN ./. sanguinea/NN from/IN one/CD nest/NN to/TO another/DT ,/, and/CC it/PRP was/VBD a/DT most/RBS interesting/JJ spectacle/NN to/TO behold/VB the/DT masters/NNS carefully/RB carrying/VBG their/PRP$ slaves/NNS in/IN their/PRP$ jaws/NNS instead/RB of/IN being/VBG carried/VBD by/IN them/PRP ,/, as/IN in/IN the/DT case/NN of/IN F/NN ./. rufescens/NNS ./. Another/DT day/NN my/PRP$ attention/NN was/VBD struck/VBD by/IN about/IN a/DT score/NN of/IN the/DT slave/NN makers/NNS haunting/JJ the/DT same/JJ spot/NN ,/, and/CC evidently/RB not/RB in/IN search/NN of/IN food/NN ;/: they/PRP approached/VBD and/CC were/VBD vigorously/RB repulsed/VBN by/IN an/DT independent/JJ community/NN of/IN the/DT slave/NN species/NN (/( F/NN ./. fusca/NN )/SYM ;/: sometimes/RB as/IN many/JJ as/IN three/CD of/IN these/DT ants/NNS clinging/VBG to/TO the/DT legs/NNS of/IN the/DT slavemaking/VBG F/NN ./. sanguinea/NN ./. 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If/IN their/PRP$ presence/NN proved/VBD useful/JJ to/TO the/DT species/NN which/WDT had/VBD seized/VBN them/PRP if/IN it/PRP were/VBD more/JJR advantageous/JJ to/TO this/DT species/NN to/TO capture/VB workers/NNS than/IN to/TO procreate/VB them/PRP the/DT habit/NN of/IN collecting/VBG pupae/NN ,/, originally/RB for/IN food/NN ,/, might/MD by/IN natural/JJ selection/NN be/VB strengthened/VBN and/CC rendered/VBN permanent/JJ for/IN the/DT very/RB different/JJ purpose/NN of/IN raising/VBG slaves/NNS ./. 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In/IN this/DT case/NN the/DT beak/NN is/VBZ supposed/VBN to/TO be/VB slowly/RB modified/VBN by/IN natural/JJ selection/NN ,/, subsequently/RB to/TO ,/, but/CC in/IN accordance/NN with/IN ,/, slowly/RB changing/VBG habits/NNS or/CC taste/NN ;/: but/CC let/VB the/DT feet/NNS of/IN the/DT titmouse/NN vary/VBP and/CC grow/VB larger/JJR from/IN correlation/NN with/IN the/DT beak/NN ,/, or/CC from/IN any/DT other/JJ unknown/JJ cause/NN ,/, and/CC it/PRP is/VBZ not/RB improbable/JJ that/IN such/JJ larger/JJR feet/NNS would/MD lead/VB the/DT bird/NN to/TO climb/VB more/JJR and/CC more/JJR until/IN it/PRP acquired/VBN the/DT remarkable/JJ climbing/VBG instinct/NN and/CC power/NN of/IN the/DT nuthatch/NN ./. In/IN this/DT case/NN a/DT gradual/JJ change/NN of/IN structure/NN is/VBZ supposed/VBN to/TO lead/VB to/TO changed/VBN instinctive/JJ habits/NNS ./. 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Moreover/RB ,/, whenever/WRB complicated/VBN experiments/NNS are/VBP in/IN progress/NN ,/, so/RB careful/JJ an/DT observer/NN as/IN Gartner/NNP would/MD have/VB castrated/VBN his/PRP$ hybrids/NNS ,/, and/CC this/DT would/MD have/VB ensured/VBD in/IN each/DT generation/NN a/DT cross/VB with/IN pollen/NN from/IN a/DT distinct/JJ flower/NN ,/, either/DT from/IN the/DT same/JJ plant/NN or/CC from/IN another/DT plant/NN of/IN the/DT same/JJ hybrid/JJ nature/NN ./. And/CC thus/RB ,/, the/DT strange/JJ fact/NN of/IN an/DT increase/NN of/IN fertility/NN in/IN the/DT successive/JJ generations/NNS of/IN artificially/RB fertilised/VBN hybrids/NNS ,/, in/IN contrast/NN with/IN those/DT spontaneously/RB self/NN fertilised/VBN ,/, may/MD ,/, as/IN I/PRP believe/VBP ,/, be/VB accounted/VBD for/IN by/IN too/RB close/VB interbreeding/VBG having/VBG been/VBN avoided/VBN ./. Now/RB let/VB us/PRP turn/VB to/TO the/DT results/NNS arrived/VBD at/IN by/IN a/DT third/JJ most/RBS experienced/VBN hybridiser/NN ,/, namely/RB ,/, the/DT Hon/NNP ./. and/CC Rev/NNP ./. W/NNP ./. Herbert/NNP ./. He/PRP is/VBZ as/IN emphatic/JJ in/IN his/PRP$ conclusion/NN that/IN some/DT hybrids/NNS are/VBP perfectly/RB fertile/JJ as/IN fertile/JJ as/IN the/DT pure/JJ parent/NN species/NN as/IN are/VBP Kolreuter/NNP and/CC Gartner/NNP that/IN some/DT degree/NN of/IN sterility/NN between/IN distinct/JJ species/NN is/VBZ a/DT universal/JJ law/NN of/IN nature/NN ./. He/PRP experimented/VBD on/IN some/DT of/IN the/DT very/RB same/JJ species/NN as/IN did/VBD Gartner/NNP ./. The/DT difference/NN in/IN their/PRP$ results/NNS may/MD ,/, I/PRP think/VBP ,/, be/VB in/IN part/NN accounted/VBD for/IN by/IN Herbert's/NNP great/JJ horticultural/JJ skill/NN ,/, and/CC by/IN his/PRP$ having/VBG hot/JJ houses/NNS at/IN his/PRP$ command/NN ./. Of/IN his/PRP$ many/JJ important/JJ statements/NNS I/PRP will/MD here/RB give/VB only/RB a/DT single/JJ one/CD as/IN an/DT example/NN ,/, namely/RB ,/, that/IN "/" every/DT ovule/NN in/IN a/DT pod/NN of/IN Crinum/NNP capense/NN fertilised/VBN by/IN C/NN ./. revolutum/NN produced/VBN a/DT plant/NN ,/, which/WDT I/PRP never/RB saw/VBD to/TO occur/VB in/IN a/DT case/NN of/IN its/PRP$ natural/JJ fecundation/NN ./. "/" So/RB that/IN here/RB we/PRP have/VBP perfect/JJ or/CC even/RB more/JJR than/IN commonly/RB perfect/JJ fertility/NN ,/, in/IN a/DT first/JJ cross/VB between/IN two/CD distinct/JJ species/NN ./. This/DT case/NN of/IN the/DT Crinum/NNP leads/VBZ me/PRP to/TO refer/VB to/TO a/DT singular/JJ fact/NN ,/, namely/RB ,/, that/IN individual/JJ plants/NNS of/IN certain/JJ species/NN of/IN Lobelia/NNP ,/, Verbascum/NNP and/CC Passiflora/NNP ,/, can/MD easily/RB be/VB fertilised/VBN by/IN pollen/NN from/IN a/DT distinct/JJ species/NN ,/, but/CC not/RB by/IN pollen/NN from/IN the/DT same/JJ plant/NN ,/, though/IN this/DT pollen/NN can/MD be/VB proved/VBD to/TO be/VB perfectly/RB sound/NN by/IN fertilising/VBG other/JJ plants/NNS or/CC species/NN ./. In/IN the/DT genus/NN Hippeastrum/NNP ,/, in/IN Corydalis/NNP as/IN shown/VBN by/IN Professor/NNP Hildebrand/NNP ,/, in/IN various/JJ orchids/NNS as/IN shown/VBN by/IN Mr/NNP ./. Scott/NNP and/CC Fritz/NNP Muller/NNP ,/, all/DT the/DT individuals/NNS are/VBP in/IN this/DT peculiar/JJ condition/NN ./. So/RB that/IN with/IN some/DT species/NN ,/, certain/JJ abnormal/JJ individuals/NNS ,/, and/CC in/IN other/JJ species/NN all/DT the/DT individuals/NNS ,/, can/MD actually/RB be/VB hybridised/VBN much/JJ more/JJR readily/RB than/IN they/PRP can/MD be/VB fertilised/VBN by/IN pollen/NN from/IN the/DT same/JJ individual/JJ plant!/NN To/TO give/VB one/CD instance/NN ,/, a/DT bulb/NN of/IN Hippeastrum/NNP aulicum/NN produced/VBN four/CD flowers/NNS ;/: three/CD were/VBD fertilised/VBN by/IN Herbert/NNP with/IN their/PRP$ own/JJ pollen/NN ,/, and/CC the/DT fourth/JJ was/VBD subsequently/RB fertilised/VBN by/IN the/DT pollen/NN of/IN a/DT compound/NN hybrid/JJ descended/VBD from/IN three/CD distinct/JJ species/NN :/: the/DT result/NN was/VBD that/IN "/" the/DT ovaries/NNS of/IN the/DT three/CD first/JJ flowers/NNS soon/RB ceased/VBD to/TO grow/VB ,/, and/CC after/IN a/DT few/JJ days/NNS perished/VBD entirely/RB ,/, whereas/IN the/DT pod/NN impregnated/VBN by/IN the/DT pollen/NN of/IN the/DT hybrid/JJ made/VBN vigorous/JJ growth/NN and/CC rapid/JJ progress/NN to/TO maturity/NN ,/, and/CC bore/VBD good/JJ seed/NN ,/, which/WDT vegetated/VBN freely/RB ./. "/" Mr/NNP ./. Herbert/NNP tried/VBD similar/JJ experiments/NNS during/IN many/JJ years/NNS ,/, and/CC always/RB with/IN the/DT same/JJ result/NN ./. These/DT cases/NNS serve/VB to/TO show/NN on/IN what/WP slight/JJ and/CC mysterious/JJ causes/NNS the/DT lesser/JJR or/CC greater/JJR fertility/NN of/IN a/DT species/NN sometimes/RB depends/VBZ ./. The/DT practical/JJ experiments/NNS of/IN horticulturists/NNS ,/, though/IN not/RB made/VBN with/IN scientific/JJ precision/NN ,/, deserve/VBP some/DT notice/NN ./. It/PRP is/VBZ notorious/JJ in/IN how/WRB complicated/VBN a/DT manner/NN the/DT species/NN of/IN Pelargonium/NNP ,/, Fuchsia/NNP ,/, Calceolaria/NNP ,/, Petunia/NNP ,/, Rhododendron/NNP ,/, &c/NN ./. ,/, have/VBP been/VBN crossed/VBD ,/, yet/RB many/JJ of/IN these/DT hybrids/NNS seed/NN freely/RB ./. For/IN instance/NN ,/, Herbert/NNP asserts/VBZ that/IN a/DT hybrid/JJ from/IN Calceolaria/NNP integrifolia/NN and/CC plantaginea/NN ,/, species/NN most/RBS widely/RB dissimilar/JJ in/IN general/JJ habit/NN ,/, "/" reproduces/VBZ itself/PRP as/IN perfectly/RB as/IN if/IN it/PRP had/VBD been/VBN a/DT natural/JJ species/NN from/IN the/DT mountains/NNS of/IN Chili/NNP ./. "/" I/PRP have/VBP taken/VBN some/DT pains/NNS to/TO ascertain/VB the/DT degree/NN of/IN fertility/NN of/IN some/DT of/IN the/DT complex/JJ crosses/VBZ of/IN rhododendrons/NNS ,/, and/CC I/PRP am/VBP assured/VBN that/IN many/JJ of/IN them/PRP are/VBP perfectly/RB fertile/JJ ./. Mr/NNP ./. C/NN ./. Noble/NNP ,/, for/IN instance/NN ,/, informs/VBZ me/PRP that/IN he/PRP raises/VBZ stocks/NNS for/IN grafting/VBG from/IN a/DT hybrid/JJ between/IN Rhod/NNP ./. ponticum/NN and/CC catawbiense/NN ,/, and/CC that/IN this/DT hybrid/JJ "/" seeds/NNS as/IN freely/RB as/IN it/PRP is/VBZ possible/JJ to/TO imagine/VB ./. "/" Had/VBD hybrids/NNS when/WRB fairly/RB treated/VBN ,/, always/RB gone/VBN on/IN decreasing/VBG in/IN fertility/NN in/IN each/DT successive/JJ generation/NN ,/, as/IN Gartner/NNP believed/VBD to/TO be/VB the/DT case/NN ,/, the/DT fact/NN would/MD have/VB been/VBN notorious/JJ to/TO nurserymen/NNS ./. Horticulturists/NNS raise/VB large/JJ beds/NNS of/IN the/DT same/JJ hybrid/JJ ,/, and/CC such/JJ alone/RB are/VBP fairly/RB treated/VBN ,/, for/IN by/IN insect/NN agency/NN the/DT several/JJ individuals/NNS are/VBP allowed/VBN to/TO cross/VB freely/RB with/IN each/DT other/JJ ,/, and/CC the/DT injurious/JJ influence/NN of/IN close/VB interbreeding/VBG is/VBZ thus/RB prevented/VBN ./. 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If/IN our/PRP$ systematic/JJ arrangements/NNS can/MD be/VB trusted/VBN ,/, that/IN is/VBZ ,/, if/IN the/DT genera/NN of/IN animals/NNS are/VBP as/IN distinct/JJ from/IN each/DT other/JJ as/IN are/VBP the/DT genera/NN of/IN plants/NNS ,/, then/RB we/PRP may/MD infer/VB that/IN animals/NNS more/JJR widely/RB distinct/JJ in/IN the/DT scale/NN of/IN nature/NN can/MD be/VB crossed/VBD more/JJR easily/RB than/IN in/IN the/DT case/NN of/IN plants/NNS ;/: but/CC the/DT hybrids/NNS themselves/PRP are/VBP ,/, I/PRP think/VBP ,/, more/JJR sterile/JJ ./. It/PRP should/MD ,/, however/RB ,/, be/VB borne/VBN in/IN mind/NN that/IN ,/, owing/JJ to/TO few/JJ animals/NNS breeding/VBG freely/RB under/IN confinement/NN ,/, few/JJ experiments/NNS have/VBP been/VBN fairly/RB tried/VBD :/: for/IN instance/NN ,/, the/DT canary/JJ bird/NN has/VBZ been/VBN crossed/VBD with/IN nine/CD distinct/JJ species/NN of/IN finches/NNS ,/, but/CC ,/, as/IN not/RB one/CD of/IN these/DT breeds/NNS freely/RB in/IN confinement/NN ,/, we/PRP have/VBP no/DT right/NN to/TO expect/VB that/IN the/DT first/JJ crosses/VBZ between/IN them/PRP and/CC the/DT canary/JJ ,/, or/CC that/IN their/PRP$ hybrids/NNS ,/, should/MD be/VB perfectly/RB fertile/JJ ./. 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But/CC the/DT fertility/NN of/IN first/JJ crosses/VBZ is/VBZ likewise/RB innately/RB variable/JJ ;/: for/IN it/PRP is/VBZ not/RB always/RB the/DT same/JJ in/IN degree/NN when/WRB the/DT same/JJ two/CD species/NN are/VBP crossed/VBD under/IN the/DT same/JJ circumstances/NNS ;/: it/PRP depends/VBZ in/IN part/NN upon/IN the/DT constitution/NN of/IN the/DT individuals/NNS which/WDT happen/VB to/TO have/VB been/VBN chosen/VBN for/IN the/DT experiment/NN ./. So/RB it/PRP is/VBZ with/IN hybrids/NNS ,/, for/IN their/PRP$ degree/NN of/IN fertility/NN is/VBZ often/RB found/VBD to/TO differ/VB greatly/RB in/IN the/DT several/JJ individuals/NNS raised/VBN from/IN seed/NN out/IN of/IN the/DT same/JJ capsule/NN and/CC exposed/VBN to/TO the/DT same/JJ conditions/NNS ./. By/IN the/DT term/NN systematic/JJ affinity/NN is/VBZ meant/VBN ,/, the/DT general/JJ resemblance/NN between/IN species/NN in/IN structure/NN and/CC constitution/NN ./. Now/RB the/DT fertility/NN of/IN first/JJ crosses/VBZ ,/, and/CC of/IN the/DT hybrids/NNS produced/VBN from/IN them/PRP ,/, is/VBZ largely/RB governed/VBN by/IN their/PRP$ systematic/JJ affinity/NN ./. This/DT is/VBZ clearly/RB shown/VBN by/IN hybrids/NNS never/RB having/VBG been/VBN raised/VBN between/IN species/NN ranked/VBD by/IN systematists/NNS in/IN distinct/JJ families/NNS ;/: and/CC on/IN the/DT other/JJ hand/NN ,/, by/IN very/RB closely/RB allied/VBN species/NN generally/RB uniting/VBG with/IN facility/NN ./. But/CC the/DT correspondence/NN between/IN systematic/JJ affinity/NN and/CC the/DT facility/NN of/IN crossing/VBG is/VBZ by/IN no/DT means/VBZ strict/JJ ./. A/DT multitude/NN of/IN cases/NNS could/MD be/VB given/VBN of/IN very/RB closely/RB allied/VBN species/NN which/WDT will/MD not/RB unite/VB ,/, or/CC only/RB with/IN extreme/JJ difficulty/NN ;/: and/CC on/IN the/DT other/JJ hand/NN of/IN very/RB distinct/JJ species/NN which/WDT unite/VB with/IN the/DT utmost/JJ facility/NN ./. In/IN the/DT same/JJ family/NN there/EX may/MD be/VB a/DT genus/NN ,/, as/IN Dianthus/NNP ,/, in/IN which/WDT very/RB many/JJ species/NN can/MD most/RBS readily/RB be/VB crossed/VBD ;/: and/CC another/DT genus/NN ,/, as/IN Silene/NNP ,/, in/IN which/WDT the/DT most/RBS persevering/VBG efforts/NNS have/VBP failed/VBD to/TO produce/VB between/IN extremely/RB close/VB species/NN a/DT single/JJ hybrid/JJ ./. Even/RB within/IN the/DT limits/NNS of/IN the/DT same/JJ genus/NN ,/, we/PRP meet/VB with/IN this/DT same/JJ difference/NN ;/: for/IN instance/NN ,/, the/DT many/JJ species/NN of/IN Nicotiana/NNP have/VBP been/VBN more/JJR largely/RB crossed/VBD than/IN the/DT species/NN of/IN almost/RB any/DT other/JJ genus/NN ;/: but/CC Gartner/NNP found/VBD that/IN N/NN ./. acuminata/NN ,/, which/WDT is/VBZ not/RB a/DT particularly/RB distinct/JJ species/NN ,/, obstinately/RB failed/VBD to/TO fertilise/NN ,/, or/CC to/TO be/VB fertilised/VBN by/IN no/DT less/JJR than/IN eight/CD other/JJ species/NN of/IN Nicotiana/NNP ./. Many/JJ analogous/JJ facts/NNS could/MD be/VB given/VBN ./. No/DT one/CD has/VBZ been/VBN able/JJ to/TO point/NN out/IN what/WP kind/NN or/CC what/WP amount/NN of/IN difference/NN ,/, in/IN any/DT recognisable/JJ character/NN ,/, is/VBZ sufficient/JJ to/TO prevent/VB two/CD species/NN crossing/VBG ./. It/PRP can/MD be/VB shown/VBN that/IN plants/NNS most/RBS widely/RB different/JJ in/IN habit/NN and/CC general/JJ appearance/NN ,/, and/CC having/VBG strongly/RB marked/VBN differences/NNS in/IN every/DT part/NN of/IN the/DT flower/NN ,/, even/RB in/IN the/DT pollen/NN ,/, in/IN the/DT fruit/NN ,/, and/CC in/IN the/DT cotyledons/NNS ,/, can/MD be/VB crossed/VBD ./. Annual/JJ and/CC perennial/JJ plants/NNS ,/, deciduous/JJ and/CC evergreen/NN trees/NNS ,/, plants/NNS inhabiting/VBG different/JJ stations/NNS and/CC fitted/VBN for/IN extremely/RB different/JJ climates/NNS ,/, can/MD often/RB be/VB crossed/VBD with/IN ease/VB ./. 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The/DT diversity/NN of/IN the/DT result/NN in/IN reciprocal/JJ crosses/VBZ between/IN the/DT same/JJ two/CD species/NN was/VBD long/JJ ago/RB observed/VBN by/IN Kolreuter/NNP ./. To/TO give/VB an/DT instance/NN :/: Mirabilis/NNP jalapa/NN can/MD easily/RB be/VB fertilised/VBN by/IN the/DT pollen/NN of/IN M/NNP ./. longiflora/NN ,/, and/CC the/DT hybrids/NNS thus/RB produced/VBN are/VBP sufficiently/RB fertile/JJ ;/: but/CC Kolreuter/NNP tried/VBD more/JJR than/IN two/CD hundred/CD times/NNS ,/, during/IN eight/CD following/VBG years/NNS ,/, to/TO fertilise/NN reciprocally/RB M/NNP ./. longiflora/NN with/IN the/DT pollen/NN of/IN M/NNP ./. jalapa/NN ,/, and/CC utterly/RB failed/VBD ./. Several/JJ other/JJ equally/RB striking/JJ cases/NNS could/MD be/VB given/VBN ./. Thuret/NNP has/VBZ observed/VBN the/DT same/JJ fact/NN with/IN certain/JJ sea/NN weeds/NNS or/CC Fuci/NNP ./. Gartner/NNP ,/, moreover/RB ,/, found/VBD that/IN this/DT difference/NN of/IN facility/NN in/IN making/VBG reciprocal/JJ crosses/VBZ is/VBZ extremely/RB common/JJ in/IN a/DT lesser/JJR degree/NN ./. He/PRP has/VBZ observed/VBN it/PRP even/RB between/IN closely/RB related/VBN forms/NNS (/( as/IN Matthiola/NNP annua/NN and/CC gilabra/NN )/SYM which/WDT many/JJ botanists/NNS rank/NN only/RB as/IN varieties/NNS ./. It/PRP is/VBZ also/RB a/DT remarkable/JJ fact/NN ,/, that/IN hybrids/NNS raised/VBN from/IN reciprocal/JJ crosses/VBZ ,/, though/IN of/IN course/NN compounded/VBN of/IN the/DT very/RB same/JJ two/CD species/NN ,/, the/DT one/CD species/NN having/VBG first/JJ been/VBN used/VBN as/IN the/DT father/NN and/CC then/RB as/IN the/DT mother/NN ,/, though/IN they/PRP rarely/RB differ/VBP in/IN external/JJ characters/NNS ,/, yet/RB generally/RB differ/VBP in/IN fertility/NN in/IN a/DT small/JJ ,/, and/CC occasionally/RB in/IN a/DT high/JJ degree/NN ./. Several/JJ other/JJ singular/JJ rules/NNS could/MD be/VB given/VBN from/IN Gartner/NNP :/: for/IN instance/NN ,/, some/DT species/NN have/VBP a/DT remarkable/JJ power/NN of/IN crossing/VBG with/IN other/JJ species/NN ;/: other/JJ species/NN of/IN the/DT same/JJ genus/NN have/VBP a/DT remarkable/JJ power/NN of/IN impressing/VBG their/PRP$ likeness/NN on/IN their/PRP$ hybrid/JJ offspring/NN ;/: but/CC these/DT two/CD powers/NNS do/VBP not/RB at/IN all/DT necessarily/RB go/VB together/RB ./. There/EX are/VBP certain/JJ hybrids/NNS which/WDT ,/, instead/RB of/IN having/VBG ,/, as/IN is/VBZ usual/JJ ,/, an/DT intermediate/JJ character/NN between/IN their/PRP$ two/CD parents/NNS ,/, always/RB closely/RB resemble/VB one/CD of/IN them/PRP ;/: and/CC such/JJ hybrids/NNS ,/, though/IN externally/RB so/RB like/IN one/CD of/IN their/PRP$ pure/JJ parent/NN species/NN ,/, are/VBP with/IN rare/JJ exceptions/NNS extremely/RB sterile/JJ ./. So/RB again/RB amongst/IN hybrids/NNS which/WDT are/VBP usually/RB intermediate/JJ in/IN structure/NN between/IN their/PRP$ parents/NNS ,/, exceptional/JJ and/CC abnormal/JJ individuals/NNS sometimes/RB are/VBP born/VBN ,/, which/WDT closely/RB resemble/VB one/CD of/IN their/PRP$ pure/JJ parents/NNS ;/: and/CC these/DT hybrids/NNS are/VBP almost/RB always/RB utterly/RB sterile/JJ ,/, even/RB when/WRB the/DT other/JJ hybrids/NNS raised/VBN from/IN seed/NN from/IN the/DT same/JJ capsule/NN have/VBP a/DT considerable/JJ degree/NN of/IN fertility/NN ./. These/DT facts/NNS show/NN how/WRB completely/RB the/DT fertility/NN of/IN a/DT hybrid/JJ may/MD be/VB independent/JJ of/IN its/PRP$ external/JJ resemblance/NN to/TO either/DT pure/JJ parent/NN ./. 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This/DT latter/NN statement/NN is/VBZ clearly/RB proved/VBD by/IN the/DT difference/NN in/IN the/DT result/NN of/IN reciprocal/JJ crosses/VBZ between/IN the/DT same/JJ two/CD species/NN ,/, for/IN ,/, according/VBG as/IN the/DT one/CD species/NN or/CC the/DT other/JJ is/VBZ used/VBN as/IN the/DT father/NN or/CC the/DT mother/NN ,/, there/EX is/VBZ generally/RB some/DT difference/NN ,/, and/CC occasionally/RB the/DT widest/JJS possible/JJ difference/NN ,/, in/IN the/DT facility/NN of/IN effecting/VBG an/DT union/NN ./. The/DT hybrids/NNS ,/, moreover/RB ,/, produced/VBN from/IN reciprocal/JJ crosses/VBZ often/RB differ/VBP in/IN fertility/NN ./. Now/RB do/VBP these/DT complex/JJ and/CC singular/JJ rules/NNS indicate/VB that/IN species/NN have/VBP been/VBN endowed/VBN with/IN sterility/NN simply/RB to/TO prevent/VB their/PRP$ becoming/VBG confounded/VBD in/IN nature/NN ?/. I/PRP think/VBP not/RB ./. 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But/CC the/DT imperfection/NN in/IN the/DT geological/JJ record/NN largely/RB results/NNS from/IN another/DT and/CC more/JJR important/JJ cause/NN than/IN any/DT of/IN the/DT foregoing/NN ;/: namely/RB ,/, from/IN the/DT several/JJ formations/NNS being/VBG separated/VBN from/IN each/DT other/JJ by/IN wide/JJ intervals/NNS of/IN time/NN ./. This/DT doctrine/NN has/VBZ been/VBN emphatically/RB admitted/VBD by/IN many/JJ geologists/NNS and/CC palaeontologists/NNS ,/, who/WP ,/, like/IN E/NN ./. Forbes/NNP ,/, entirely/RB disbelieve/VB in/IN the/DT change/NN of/IN species/NN ./. When/WRB we/PRP see/VB the/DT formations/NNS tabulated/VBN in/IN written/VBN works/NNS ,/, or/CC when/WRB we/PRP follow/VB them/PRP in/IN nature/NN ,/, it/PRP is/VBZ difficult/JJ to/TO avoid/VB believing/VBG that/IN they/PRP are/VBP closely/RB consecutive/JJ ./. But/CC we/PRP know/VB ,/, for/IN instance/NN ,/, from/IN Sir/NNP R/NN ./. 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We/PRP can/MD ,/, I/PRP think/VBP ,/, see/VB why/WRB the/DT geological/JJ formations/NNS of/IN each/DT region/NN are/VBP almost/RB invariably/RB intermittent/JJ ;/: that/IN is/VBZ ,/, have/VBP not/RB followed/VBD each/DT other/JJ in/IN close/VB sequence/NN ./. Scarcely/RB any/DT fact/NN struck/VBD me/PRP more/JJR when/WRB examining/VBG many/JJ hundred/CD miles/NNS of/IN the/DT South/NNP American/NNP coasts/NNS ,/, which/WDT have/VBP been/VBN upraised/VBN several/JJ hundred/CD feet/NNS within/IN the/DT recent/JJ period/NN ,/, than/IN the/DT absence/NN of/IN any/DT recent/JJ deposits/NNS sufficiently/RB extensive/JJ to/TO last/JJ for/IN even/RB a/DT short/JJ geological/JJ period/NN ./. 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But/CC certain/JJ Jurassic/NNP and/CC Triassic/NNP forms/NNS are/VBP now/RB commonly/RB admitted/VBD to/TO be/VB teleostean/NN ;/: and/CC even/RB some/DT palaeozoic/JJ forms/NNS have/VBP thus/RB been/VBN classed/VBN by/IN one/CD high/JJ authority/NN ./. If/IN the/DT teleosteans/NNS had/VBD really/RB appeared/VBD suddenly/RB in/IN the/DT northern/JJ hemisphere/NN at/IN the/DT commencement/NN of/IN the/DT chalk/NN formation/NN the/DT fact/NN would/MD have/VB been/VBN highly/RB remarkable/JJ ;/: but/CC it/PRP would/MD not/RB have/VBP formed/VBN an/DT insuperable/JJ difficulty/NN ,/, unless/IN it/PRP could/MD likewise/RB have/VBP been/VBN shown/VBN that/IN at/IN the/DT same/JJ period/NN the/DT species/NN were/VBD suddenly/RB and/CC simultaneously/RB developed/VBN in/IN other/JJ quarters/NNS of/IN the/DT world/NN ./. 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Even/RB at/IN this/DT day/NN ,/, if/IN the/DT Malay/NNP Archipelago/NNP were/VBD converted/VBN into/IN land/NN ,/, the/DT tropical/JJ parts/NNS of/IN the/DT Indian/NNP Ocean/NNP would/MD form/NN a/DT large/JJ and/CC perfectly/RB enclosed/VBN basin/NN ,/, in/IN which/WDT any/DT great/JJ group/NN of/IN marine/NN animals/NNS might/MD be/VB multiplied/VBN :/: and/CC here/RB they/PRP would/MD remain/VB confined/VBN ,/, until/IN some/DT of/IN the/DT species/NN became/VBD adapted/VBN to/TO a/DT cooler/JJR climate/NN ,/, and/CC were/VBD enabled/VBD to/TO double/JJ the/DT Southern/NNP capes/NNS of/IN Africa/NNP or/CC Australia/NNP ,/, and/CC thus/RB reach/VB other/JJ and/CC distant/JJ seas/NNS ./. From/IN these/DT considerations/NNS ,/, from/IN our/PRP$ ignorance/NN of/IN the/DT geology/NN of/IN other/JJ countries/NNS beyond/IN the/DT confines/NNS of/IN Europe/NNP and/CC the/DT United/NNP States/NNPS ,/, and/CC from/IN the/DT revolution/NN in/IN our/PRP$ palaeontological/JJ knowledge/NN effected/VBN by/IN the/DT discoveries/NNS of/IN the/DT last/JJ dozen/NN years/NNS ,/, it/PRP seems/VBZ to/TO me/PRP to/TO be/VB about/IN as/IN rash/NN to/TO dogmatize/VB on/IN the/DT succession/NN of/IN organic/JJ forms/NNS throughout/IN the/DT world/NN ,/, as/IN it/PRP would/MD be/VB for/IN a/DT naturalist/NN to/TO land/NN for/IN five/CD minutes/NNS on/IN a/DT barren/JJ point/NN in/IN Australia/NNP ,/, and/CC then/RB to/TO discuss/VB the/DT number/NN and/CC range/NN of/IN its/PRP$ productions/NNS ./. On/IN the/DT Sudden/JJ Appearance/NN of/IN Groups/NNS of/IN allied/VBN Species/NNP in/IN the/DT lowest/JJS known/VBN Fossiliferous/NNP Strata/NNP There/EX is/VBZ another/DT and/CC allied/VBN difficulty/NN ,/, which/WDT is/VBZ much/JJ more/JJR serious/JJ ./. I/PRP allude/NN to/TO the/DT manner/NN in/IN which/WDT species/NN belonging/VBG to/TO several/JJ of/IN the/DT main/JJ divisions/NNS of/IN the/DT animal/NN kingdom/NN suddenly/RB appear/VB in/IN the/DT lowest/JJS known/VBN fossiliferous/JJ rocks/NNS ./. Most/JJS of/IN the/DT arguments/NNS which/WDT have/VBP convinced/VBN me/PRP that/IN all/DT the/DT existing/VBG species/NN of/IN the/DT same/JJ group/NN are/VBP descended/VBD from/IN a/DT single/JJ progenitor/NN ,/, apply/VB with/IN equal/JJ force/NN to/TO the/DT earliest/JJS known/VBN species/NN ./. For/IN instance/NN ,/, it/PRP cannot/MD be/VB doubted/VBD that/IN all/DT the/DT Cambrian/NNP and/CC Silurian/NNP trilobites/NNS are/VBP descended/VBD from/IN some/DT one/CD crustacean/NN ,/, which/WDT must/MD have/VB lived/VBD long/JJ before/IN the/DT Cambrian/NNP age/NN ,/, and/CC which/WDT probably/RB differed/VBD greatly/RB from/IN any/DT known/VBN animal/NN ./. Some/DT of/IN the/DT most/RBS ancient/JJ animals/NNS ,/, as/IN the/DT Nautilus/NNP ,/, Lingula/NNP ,/, &c/NN ./. ,/, do/VBP not/RB differ/VBP much/JJ from/IN living/VBG species/NN ;/: and/CC it/PRP cannot/MD on/IN our/PRP$ theory/NN be/VB supposed/VBN ,/, that/IN these/DT old/JJ species/NN were/VBD the/DT progenitors/NNS of/IN all/DT the/DT species/NN belonging/VBG to/TO the/DT same/JJ groups/NNS which/WDT have/VBP subsequently/RB appeared/VBD ,/, for/IN they/PRP are/VBP not/RB in/IN any/DT degree/NN intermediate/JJ in/IN character/NN ./. Consequently/RB ,/, if/IN the/DT theory/NN be/VB true/JJ ,/, it/PRP is/VBZ indisputable/JJ that/IN before/IN the/DT lowest/JJS Cambrian/NNP stratum/NN was/VBD deposited/VBN ,/, long/JJ periods/NNS elapsed/VBN ,/, as/IN long/JJ as/IN ,/, or/CC probably/RB far/RB longer/RB than/IN ,/, the/DT whole/JJ interval/NN from/IN the/DT Cambrian/NNP age/NN to/TO the/DT present/JJ day/NN ;/: and/CC that/IN during/IN these/DT vast/JJ periods/NNS the/DT world/NN swarmed/VBD with/IN living/VBG creatures/NNS ./. Here/RB we/PRP encounter/NN a/DT formidable/JJ objection/NN ;/: for/IN it/PRP seems/VBZ doubtful/JJ whether/IN the/DT earth/NN ,/, in/IN a/DT fit/VB state/NN for/IN the/DT habitation/NN of/IN living/VBG creatures/NNS ,/, has/VBZ lasted/VBN long/JJ enough/RB ./. Sir/NNP W/NNP ./. Thompson/NNP concludes/VBZ that/IN the/DT consolidation/NN of/IN the/DT crust/NN can/MD hardly/RB have/VBP occurred/VBD less/JJR than/IN 20/CD or/CC more/JJR than/IN 400/CD million/CD years/NNS ago/RB ,/, but/CC probably/RB not/RB less/JJR than/IN 98/NN or/CC more/JJR than/IN 200/CD million/CD years/NNS ./. These/DT very/RB wide/JJ limits/NNS show/NN how/WRB doubtful/JJ the/DT data/NNS are/VBP ;/: and/CC other/JJ elements/NNS may/MD have/VB hereafter/RB to/TO be/VB introduced/VBN into/IN the/DT problem/NN ./. Mr/NNP ./. Croll/NNP estimates/NNS that/IN about/IN 60/CD million/CD years/NNS have/VBP elapsed/VBN since/IN the/DT Cambrian/NNP period/NN ,/, but/CC this/DT ,/, judging/VBG from/IN the/DT small/JJ amount/NN of/IN organic/JJ change/NN since/IN the/DT commencement/NN of/IN the/DT Glacial/NNP epoch/NN ,/, appears/VBZ a/DT very/RB short/JJ time/NN for/IN the/DT many/JJ and/CC great/JJ mutations/NNS of/IN life/NN ,/, which/WDT have/VBP certainly/RB occurred/VBD since/IN the/DT Cambrian/NNP formation/NN ;/: and/CC the/DT previous/JJ 140/CD million/CD years/NNS can/MD hardly/RB be/VB considered/VBN as/IN sufficient/JJ for/IN the/DT development/NN of/IN the/DT varied/VBN forms/NNS of/IN life/NN which/WDT already/RB existed/VBD during/IN the/DT Cambrian/NNP period/NN ./. It/PRP is/VBZ ,/, however/RB ,/, probable/JJ ,/, as/IN Sir/NNP William/NNP Thompson/NNP insists/VBZ ,/, that/IN the/DT world/NN at/IN a/DT very/RB early/JJ period/NN was/VBD subjected/VBN to/TO more/JJR rapid/JJ and/CC violent/JJ changes/NNS in/IN its/PRP$ physical/JJ conditions/NNS than/IN those/DT now/RB occurring/VBG ;/: and/CC such/JJ changes/NNS would/MD have/VB tended/VBD to/TO induce/VB changes/NNS at/IN a/DT corresponding/JJ rate/NN in/IN the/DT organisms/NNS which/WDT then/RB existed/VBD ./. To/TO the/DT question/NN why/WRB we/PRP do/VBP not/RB find/VB rich/JJ fossiliferous/JJ deposits/NNS belonging/VBG to/TO these/DT assumed/VBN earliest/JJS periods/NNS prior/RB to/TO the/DT Cambrian/NNP system/NN ,/, I/PRP can/MD give/VB no/DT satisfactory/JJ answer/NN ./. Several/JJ eminent/JJ geologists/NNS ,/, with/IN Sir/NNP R/NN ./. 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Hicks/NNP has/VBZ found/VBN in/IN South/NNP Wales/NNP beds/NNS rich/JJ in/IN trilobites/NNS ,/, and/CC containing/VBG various/JJ molluscs/NNS and/CC annelids/NNS ./. The/DT presence/NN of/IN phosphatic/JJ nodules/NNS and/CC bituminous/JJ matter/NN ,/, even/RB in/IN some/DT of/IN the/DT lowest/JJS azoic/JJ rocks/NNS ,/, probably/RB indicates/VBZ life/NN at/IN these/DT periods/NNS ;/: and/CC the/DT existence/NN of/IN the/DT Eozoon/NNP in/IN the/DT Laurentian/NNP formation/NN of/IN Canada/NNP is/VBZ generally/RB admitted/VBD ./. There/EX are/VBP three/CD great/JJ series/NN of/IN strata/NNS beneath/IN the/DT Silurian/NNP system/NN in/IN Canada/NNP ,/, in/IN the/DT lowest/JJS of/IN which/WDT the/DT Eozoon/NNP is/VBZ found/VBN ./. Sir/NNP W/NNP ./. Logan/NNP states/NNS that/IN their/PRP$ "/" united/VBN thickness/NN may/MD possibly/RB far/RB surpass/VB that/IN of/IN all/DT the/DT succeeding/VBG rocks/NNS ,/, from/IN the/DT base/NN of/IN the/DT palaeozoic/JJ series/NN to/TO the/DT present/JJ time/NN ./. We/PRP are/VBP thus/RB carried/VBD back/RB to/TO a/DT period/NN so/RB remote/JJ ,/, that/IN the/DT appearance/NN of/IN the/DT so/RB called/VBN primordial/JJ fauna/NNS (/( of/IN Barrande/NNP )/SYM may/MD by/IN some/DT be/VB considered/VBN as/IN a/DT comparatively/RB modern/JJ event/NN ./. "/" The/DT Eozoon/NNP belongs/VBZ to/TO the/DT most/RBS lowly/JJ organised/VBD ,/, of/IN all/DT classes/NNS of/IN animals/NNS ,/, but/CC is/VBZ highly/RB organised/VBD for/IN its/PRP$ class/NN ;/: it/PRP existed/VBD in/IN countless/JJ numbers/NNS ,/, and/CC ,/, as/IN Dr/NNP ./. Dawson/NNP has/VBZ remarked/VBN ,/, certainly/RB preyed/VBN on/IN other/JJ minute/NN organic/JJ beings/NNS ,/, which/WDT must/MD have/VB lived/VBD in/IN great/JJ numbers/NNS ./. Thus/RB the/DT words/NNS ,/, which/WDT I/PRP wrote/VBD in/IN 1859/CD ,/, about/IN the/DT existence/NN of/IN living/VBG beings/NNS long/JJ before/IN the/DT Cambrian/NNP period/NN ,/, and/CC which/WDT are/VBP almost/RB the/DT same/JJ with/IN those/DT since/IN used/VBN by/IN Sir/NNP W/NNP ./. Logan/NNP ,/, have/VBP proved/VBD true/JJ ./. Nevertheless/RB ,/, the/DT difficulty/NN of/IN assigning/VBG any/DT good/JJ reason/NN for/IN the/DT absence/NN of/IN vast/JJ piles/NNS of/IN strata/NNS rich/JJ in/IN fossils/NNS beneath/IN the/DT Cambrian/NNP system/NN is/VBZ very/RB great/JJ ./. It/PRP does/VBZ not/RB seem/VB probable/JJ that/IN the/DT most/RBS ancient/JJ beds/NNS have/VBP been/VBN quite/RB worn/VBN away/RB by/IN denudation/NN ,/, or/CC that/IN their/PRP$ fossils/NNS have/VBP been/VBN wholly/RB obliterated/VBN by/IN metamorphic/JJ action/NN ,/, for/IN if/IN this/DT had/VBD been/VBN the/DT case/NN we/PRP should/MD have/VB found/VBD only/RB small/JJ remnants/NNS of/IN the/DT formations/NNS next/JJ succeeding/VBG them/PRP in/IN age/NN ,/, and/CC these/DT would/MD always/RB have/VBP existed/VBD in/IN partially/RB metamorphosed/VBN condition/NN ./. But/CC the/DT descriptions/NNS which/WDT we/PRP possess/VBP of/IN the/DT Silurian/NNP deposits/NNS over/IN immense/JJ territories/NNS in/IN Russia/NNP and/CC in/IN North/NNP America/NNP ,/, do/VBP not/RB support/NN the/DT view/NN ,/, that/IN the/DT older/JJR a/DT formation/NN is/VBZ ,/, the/DT more/JJR invariably/RB it/PRP has/VBZ suffered/VBN extreme/JJ denudation/NN and/CC metamorphism/NN ./. The/DT case/NN at/IN present/JJ must/MD remain/VB inexplicable/JJ ;/: and/CC may/MD be/VB truly/RB urged/VBD as/IN a/DT valid/JJ argument/NN against/IN the/DT views/NNS here/RB entertained/VBN ./. To/TO show/NN that/IN it/PRP may/MD hereafter/RB receive/VB some/DT explanation/NN ,/, I/PRP will/MD give/VB the/DT following/VBG hypothesis/NN ./. 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This/DT process/NN ,/, whilst/NN it/PRP leaves/VBZ the/DT embryo/NN almost/RB unaltered/JJ ,/, continually/RB adds/VBZ ,/, in/IN the/DT course/NN of/IN successive/JJ generations/NNS ,/, more/JJR and/CC more/JJR difference/NN to/TO the/DT adult/NN ./. Thus/RB the/DT embryo/NN comes/VBZ to/TO be/VB left/VBN as/IN a/DT sort/NN of/IN picture/NN ,/, preserved/VBN by/IN nature/NN ,/, of/IN the/DT former/JJ and/CC less/JJR modified/VBN condition/NN of/IN the/DT species/NN ./. This/DT view/NN may/MD be/VB true/JJ ,/, and/CC yet/RB may/MD never/RB be/VB capable/JJ of/IN proof/NN ./. Seeing/VBG ,/, for/IN instance/NN ,/, that/IN the/DT oldest/JJS known/VBN mammals/NNS ,/, reptiles/NNS ,/, and/CC fishes/NNS strictly/RB belong/VB to/TO their/PRP$ proper/JJ classes/NNS ,/, though/IN some/DT of/IN these/DT old/JJ forms/NNS are/VBP in/IN a/DT slight/JJ degree/NN less/JJR distinct/JJ from/IN each/DT other/JJ than/IN are/VBP the/DT typical/JJ members/NNS of/IN the/DT same/JJ groups/NNS at/IN the/DT present/JJ day/NN ,/, it/PRP would/MD be/VB vain/JJ to/TO look/VB for/IN animals/NNS having/VBG the/DT common/JJ embryological/JJ character/NN of/IN the/DT Vertebrata/NNP ,/, until/IN beds/NNS rich/JJ in/IN fossils/NNS are/VBP discovered/VBN far/RB beneath/IN the/DT lowest/JJS Cambrian/NNP strata/NNS a/DT discovery/NN of/IN which/WDT the/DT chance/NN is/VBZ small/JJ ./. On/IN the/DT Succession/NN of/IN the/DT same/JJ Types/NNS within/IN the/DT same/JJ Areas/NNS ,/, during/IN the/DT later/RB Tertiary/NNP periods/NNS Mr/NNP ./. Clift/NNP many/JJ years/NNS ago/RB showed/VBD that/IN the/DT fossil/JJ mammals/NNS from/IN the/DT Australian/JJ caves/NNS were/VBD closely/RB allied/VBN to/TO the/DT living/VBG marsupials/NNS of/IN that/IN continent/NN ./. In/IN South/NNP America/NNP a/DT similar/JJ relationship/NN is/VBZ manifest/JJ ,/, even/RB to/TO an/DT uneducated/JJ eye/NN ,/, in/IN the/DT gigantic/JJ pieces/NNS of/IN armour/NN ,/, like/IN those/DT of/IN the/DT armadillo/NN ,/, found/VBD in/IN several/JJ parts/NNS of/IN La/NNP Plata/NNP ;/: and/CC Professor/NNP Owen/NNP has/VBZ shown/VBN in/IN the/DT most/RBS striking/JJ manner/NN that/IN most/RBS of/IN the/DT fossil/JJ mammals/NNS ,/, buried/VBN there/EX in/IN such/JJ numbers/NNS ,/, are/VBP related/VBN to/TO South/NNP American/NNP types/NNS ./. This/DT relationship/NN is/VBZ even/RB more/JJR clearly/RB seen/VBN in/IN the/DT wonderful/JJ collection/NN of/IN fossil/JJ bones/NNS made/VBN by/IN MM/NNP ./. Lund/NNP and/CC Clausen/NNP in/IN the/DT caves/NNS of/IN Brazil/NNP ./. I/PRP was/VBD so/RB much/JJ impressed/VBN with/IN these/DT facts/NNS that/IN I/PRP strongly/RB insisted/VBD ,/, in/IN 1839/CD and/CC 1845/CD ,/, on/IN this/DT "/" law/NN of/IN the/DT succession/NN of/IN types/NNS ,/, "/" on/IN "/" this/DT wonderful/JJ relationship/NN in/IN the/DT same/JJ continent/NN between/IN the/DT dead/JJ and/CC the/DT living/VBG ./. "/" Professor/NNP Owen/NNP has/VBZ subsequently/RB extended/VBN the/DT same/JJ generalisation/NN to/TO the/DT mammals/NNS of/IN the/DT Old/NNP World/NNP ./. We/PRP see/VB the/DT same/JJ law/NN in/IN this/DT author's/NNS restorations/NNS of/IN the/DT extinct/JJ and/CC gigantic/JJ birds/NNS of/IN New/NNP Zealand/NNP ./. We/PRP see/VB it/PRP also/RB in/IN the/DT birds/NNS of/IN the/DT caves/NNS of/IN Brazil/NNP ./. Mr/NNP ./. 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Or/CC ,/, again/RB ,/, we/PRP may/MD compare/VB the/DT productions/NNS of/IN South/NNP America/NNP south/RB of/IN lat/NN ./. 35/CD with/IN those/DT north/RB of/IN 25/CD ,/, which/WDT consequently/RB are/VBP separated/VBN by/IN a/DT space/NN of/IN ten/CD degrees/NNS of/IN latitude/NN ,/, and/CC are/VBP exposed/VBN to/TO considerably/RB different/JJ conditions/NNS ;/: yet/RB they/PRP are/VBP incomparably/RB more/JJR closely/RB related/VBN to/TO each/DT other/JJ than/IN they/PRP are/VBP to/TO the/DT productions/NNS of/IN Australia/NNP or/CC Africa/NNP under/IN nearly/RB the/DT same/JJ climate/NN ./. Analogous/JJ facts/NNS could/MD be/VB given/VBN with/IN respect/NN to/TO the/DT inhabitants/NNS of/IN the/DT sea/NN ./. A/DT second/JJ great/JJ fact/NN which/WDT strikes/NNS us/PRP in/IN our/PRP$ general/JJ review/NN is/VBZ ,/, that/IN barriers/NNS of/IN any/DT kind/NN ,/, or/CC obstacles/NNS to/TO free/JJ migration/NN ,/, are/VBP related/VBN in/IN a/DT close/VB and/CC important/JJ manner/NN to/TO the/DT differences/NNS between/IN the/DT productions/NNS of/IN various/JJ regions/NNS ./. We/PRP see/VB this/DT in/IN the/DT great/JJ difference/NN in/IN nearly/RB all/DT the/DT terrestrial/JJ productions/NNS of/IN the/DT New/NNP and/CC Old/NNP Worlds/NNPS ,/, excepting/VBG in/IN the/DT northern/JJ parts/NNS ,/, where/WRB the/DT land/NN almost/RB joins/VBZ ,/, and/CC where/WRB ,/, under/IN a/DT slightly/RB different/JJ climate/NN ,/, there/EX might/MD have/VB been/VBN free/JJ migration/NN for/IN the/DT northern/JJ temperate/JJ forms/NNS ,/, as/IN there/EX now/RB is/VBZ for/IN the/DT strictly/RB arctic/JJ productions/NNS ./. We/PRP see/VB the/DT same/JJ fact/NN in/IN the/DT great/JJ difference/NN between/IN the/DT inhabitants/NNS of/IN Australia/NNP ,/, Africa/NNP ,/, and/CC South/NNP America/NNP under/IN the/DT same/JJ latitude/NN ;/: for/IN these/DT countries/NNS are/VBP almost/RB as/IN much/JJ isolated/VBN from/IN each/DT other/JJ as/IN is/VBZ possible/JJ ./. 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Some/DT few/JJ families/NNS ,/, many/JJ sub/NN families/NNS ,/, very/RB many/JJ genera/NN ,/, and/CC a/DT still/RB greater/JJR number/NN of/IN sections/NNS of/IN genera/NN ,/, are/VBP confined/VBN to/TO a/DT single/JJ region/NN ;/: and/CC it/PRP has/VBZ been/VBN observed/VBN by/IN several/JJ naturalists/NNS that/IN the/DT most/RBS natural/JJ genera/NN ,/, or/CC those/DT genera/NN in/IN which/WDT the/DT species/NN are/VBP most/RBS closely/RB related/VBN to/TO each/DT other/JJ ,/, are/VBP generally/RB confined/VBN to/TO the/DT same/JJ ,/, country/NN ,/, or/CC if/IN they/PRP have/VBP a/DT wide/JJ range/NN that/IN their/PRP$ range/NN is/VBZ continuous/JJ ./. What/WP a/DT strange/JJ anomaly/NN it/PRP would/MD be/VB ,/, if/IN a/DT directly/RB opposite/JJ rule/NN were/VBD to/TO prevail/VB ,/, when/WRB we/PRP go/VB down/RB one/CD step/NN lower/JJR in/IN the/DT series/NN ,/, namely/RB ,/, to/TO the/DT individuals/NNS of/IN the/DT same/JJ species/NN ,/, and/CC these/DT had/VBD not/RB been/VBN ,/, at/IN least/JJS at/IN first/JJ ,/, confined/VBN to/TO some/DT one/CD region!/NN Hence/RB it/PRP seems/VBZ to/TO me/PRP ,/, as/IN it/PRP has/VBZ to/TO many/JJ other/JJ naturalists/NNS ,/, that/IN the/DT view/NN of/IN each/DT species/NN having/VBG been/VBN produced/VBN in/IN one/CD area/NN alone/RB ,/, and/CC having/VBG subsequently/RB migrated/VBN from/IN that/IN area/NN as/IN far/RB as/IN its/PRP$ powers/NNS of/IN migration/NN and/CC subsistence/NN under/IN past/JJ and/CC present/JJ conditions/NNS permitted/VBN ,/, is/VBZ the/DT most/RBS probable/JJ ./. Undoubtedly/RB many/JJ cases/NNS occur/VB ,/, in/IN which/WDT we/PRP cannot/MD explain/VB how/WRB the/DT same/JJ species/NN could/MD have/VB passed/VBN from/IN one/CD point/NN to/TO the/DT other/JJ ./. But/CC the/DT geographical/JJ and/CC climatal/JJ changes/NNS which/WDT have/VBP certainly/RB occurred/VBD within/IN recent/JJ geological/JJ times/NNS ,/, must/MD have/VB rendered/VBN discontinuous/JJ the/DT formerly/RB continuous/JJ range/NN of/IN many/JJ species/NN ./. So/RB that/IN we/PRP are/VBP reduced/VBN to/TO consider/VB whether/IN the/DT exceptions/NNS to/TO continuity/NN of/IN range/NN are/VBP so/RB numerous/JJ and/CC of/IN so/RB grave/JJ a/DT nature/NN ,/, that/IN we/PRP ought/MD to/TO give/VB up/IN the/DT belief/NN ,/, rendered/VBN probable/JJ by/IN general/JJ considerations/NNS ,/, that/IN each/DT species/NN has/VBZ been/VBN produced/VBN within/IN one/CD area/NN ,/, and/CC has/VBZ migrated/VBN thence/RB as/IN far/RB as/IN it/PRP could/MD ./. It/PRP would/MD be/VB hopelessly/RB tedious/JJ to/TO discuss/VB all/DT the/DT exceptional/JJ cases/NNS of/IN the/DT same/JJ species/NN ,/, now/RB living/VBG at/IN distant/JJ and/CC separated/VBN points/NNS ,/, nor/CC do/VBP I/PRP for/IN a/DT moment/NN pretend/VB that/IN any/DT explanation/NN could/MD be/VB offered/VBN of/IN many/JJ instances/NNS ./. But/CC ,/, after/IN some/DT preliminary/JJ remarks/NNS ,/, I/PRP will/MD discuss/VB a/DT few/JJ of/IN the/DT most/RBS striking/JJ classes/NNS of/IN facts/NNS ;/: namely/RB ,/, the/DT existence/NN of/IN the/DT same/JJ species/NN on/IN the/DT summits/NNS of/IN distant/JJ mountain/NN ranges/NNS ,/, and/CC at/IN distant/JJ points/NNS in/IN the/DT arctic/JJ and/CC antarctic/JJ regions/NNS ;/: and/CC secondly/RB (/( in/IN the/DT following/VBG chapter/NN )/SYM ,/, the/DT wide/JJ distribution/NN of/IN fresh/JJ water/NN productions/NNS ;/: and/CC thirdly/RB ,/, the/DT occurrence/NN of/IN the/DT same/JJ terrestrial/JJ species/NN on/IN islands/NNS and/CC on/IN the/DT nearest/JJS mainland/NN ,/, though/IN separated/VBN by/IN hundreds/NNS of/IN miles/NNS of/IN open/JJ sea/NN ./. If/IN the/DT existence/NN of/IN the/DT same/JJ species/NN at/IN distant/JJ and/CC isolated/VBN points/NNS of/IN the/DT earth's/NNS surface/NN ,/, can/MD in/IN many/JJ instances/NNS be/VB explained/VBD on/IN the/DT view/NN of/IN each/DT species/NN having/VBG migrated/VBN from/IN a/DT single/JJ birthplace/NN ;/: then/RB ,/, considering/VBG our/PRP$ ignorance/NN with/IN respect/NN to/TO former/JJ climatal/JJ and/CC geographical/JJ changes/NNS and/CC to/TO the/DT various/JJ occasional/JJ means/VBZ of/IN transport/NN ,/, the/DT belief/NN that/IN a/DT single/JJ birthplace/NN is/VBZ the/DT law/NN ,/, seems/VBZ to/TO me/PRP incomparably/RB the/DT safest/JJS ./. In/IN discussing/VBG this/DT subject/NN ,/, we/PRP shall/MD be/VB enabled/VBD at/IN the/DT same/JJ time/NN to/TO consider/VB a/DT point/NN equally/RB important/JJ for/IN us/PRP ,/, namely/RB ,/, whether/IN the/DT several/JJ species/NN of/IN a/DT genus/NN which/WDT must/MD on/IN our/PRP$ theory/NN all/DT be/VB descended/VBD from/IN a/DT common/JJ progenitor/NN ,/, can/MD have/VB migrated/VBN ,/, undergoing/VBG modification/NN during/IN their/PRP$ migration/NN ,/, from/IN some/DT one/CD area/NN ./. If/IN ,/, when/WRB most/RBS of/IN the/DT species/NN inhabiting/VBG one/CD region/NN are/VBP different/JJ from/IN those/DT of/IN another/DT region/NN ,/, though/IN closely/RB allied/VBN to/TO them/PRP ,/, it/PRP can/MD be/VB shown/VBN that/IN migration/NN from/IN the/DT one/CD region/NN to/TO the/DT other/JJ has/VBZ probably/RB occurred/VBD at/IN some/DT former/JJ period/NN ,/, our/PRP$ general/JJ view/NN will/MD be/VB much/JJ strengthened/VBN ;/: for/IN the/DT explanation/NN is/VBZ obvious/JJ on/IN the/DT principle/NN of/IN descent/NN with/IN modification/NN ./. A/DT volcanic/JJ island/NN ,/, for/IN instance/NN ,/, upheaved/VBN and/CC formed/VBN at/IN the/DT distance/NN of/IN a/DT few/JJ hundreds/NNS of/IN miles/NNS from/IN a/DT continent/NN ,/, would/MD probably/RB receive/VB from/IN it/PRP in/IN the/DT course/NN of/IN time/NN a/DT few/JJ colonists/NNS ,/, and/CC their/PRP$ descendants/NNS ,/, though/IN modified/VBN ,/, would/MD still/RB be/VB related/VBN by/IN inheritance/NN to/TO the/DT inhabitants/NNS of/IN that/IN continent/NN ./. Cases/NNS of/IN this/DT nature/NN are/VBP common/JJ ,/, and/CC are/VBP ,/, as/IN we/PRP shall/MD hereafter/RB see/VB ,/, inexplicable/JJ on/IN the/DT theory/NN of/IN independent/JJ creation/NN ./. This/DT view/NN of/IN the/DT relation/NN of/IN the/DT species/NN of/IN one/CD region/NN to/TO those/DT of/IN another/DT ,/, does/VBZ not/RB differ/VBP much/JJ from/IN that/IN advanced/VBD by/IN Mr/NNP ./. Wallace/NNP ,/, who/WP concludes/VBZ that/IN "/" every/DT species/NN has/VBZ come/VB into/IN existence/NN coincident/JJ both/DT in/IN space/NN and/CC time/NN with/IN a/DT pre/NN existing/VBG closely/RB allied/VBN species/NN ./. "/" And/CC it/PRP is/VBZ now/RB well/RB known/VBN that/IN he/PRP attributes/NNS this/DT coincidence/NN to/TO descent/NN with/IN modification/NN ./. The/DT question/NN of/IN single/JJ or/CC multiple/JJ centres/NNS of/IN creation/NN differs/VBZ from/IN another/DT though/IN allied/VBN question/NN ,/, namely/RB ,/, whether/IN all/DT the/DT individuals/NNS of/IN the/DT same/JJ species/NN are/VBP descended/VBD from/IN a/DT single/JJ pair/NN ,/, or/CC single/JJ hermaphrodite/NN ,/, or/CC whether/IN ,/, as/IN some/DT authors/NNS suppose/VBP ,/, from/IN many/JJ individuals/NNS simultaneously/RB created/VBN ./. With/IN organic/JJ beings/NNS which/WDT never/RB intercross/NN ,/, if/IN such/JJ exist/VB ,/, each/DT species/NN must/MD be/VB descended/VBD from/IN a/DT succession/NN of/IN modified/VBN varieties/NNS ,/, that/IN have/VBP supplanted/VBN each/DT other/JJ ,/, but/CC have/VBP never/RB blended/JJ with/IN other/JJ individuals/NNS or/CC varieties/NNS of/IN the/DT same/JJ species/NN ;/: so/RB that/IN ,/, at/IN each/DT successive/JJ stage/NN of/IN modification/NN ,/, all/DT the/DT individuals/NNS of/IN the/DT same/JJ form/NN will/MD be/VB descended/VBD from/IN a/DT single/JJ parent/NN ./. But/CC in/IN the/DT great/JJ majority/NN of/IN cases/NNS ,/, namely/RB ,/, with/IN all/DT organisms/NNS which/WDT habitually/RB unite/VB for/IN each/DT birth/NN ,/, or/CC which/WDT occasionally/RB intercross/NN ,/, the/DT individuals/NNS of/IN the/DT same/JJ species/NN inhabiting/VBG the/DT same/JJ area/NN will/MD be/VB kept/VBD nearly/RB uniform/NN by/IN intercrossing/VBG ;/: so/RB that/IN many/JJ individuals/NNS will/MD go/VB on/IN simultaneously/RB changing/VBG ,/, and/CC the/DT whole/JJ amount/NN of/IN modification/NN at/IN each/DT stage/NN will/MD not/RB be/VB due/JJ to/TO descent/NN from/IN a/DT single/JJ parent/NN ./. To/TO illustrate/VB what/WP I/PRP mean/VB :/: our/PRP$ English/NNP race/NN horses/NNS differ/VBP from/IN the/DT horses/NNS of/IN every/DT other/JJ breed/NN ;/: but/CC they/PRP do/VBP not/RB owe/VBP their/PRP$ difference/NN and/CC superiority/NN to/TO descent/NN from/IN any/DT single/JJ pair/NN ,/, but/CC to/TO continued/VBD care/NN in/IN the/DT selecting/VBG and/CC training/NN of/IN many/JJ individuals/NNS during/IN each/DT generation/NN ./. Before/IN discussing/VBG the/DT three/CD classes/NNS of/IN facts/NNS ,/, which/WDT I/PRP have/VBP selected/VBN as/IN presenting/VBG the/DT greatest/JJS amount/NN of/IN difficulty/NN on/IN the/DT theory/NN of/IN "/" single/JJ centres/NNS of/IN creation/NN ,/, "/" I/PRP must/MD say/VB a/DT few/JJ words/NNS on/IN the/DT means/VBZ of/IN dispersal/NN ./. Means/NNP of/IN Dispersal/NNP Sir/NNP C/NN ./. Lyell/NNP and/CC other/JJ authors/NNS have/VBP ably/RB treated/VBN this/DT subject/NN ./. I/PRP can/MD give/VB here/RB only/RB the/DT briefest/JJS abstract/JJ of/IN the/DT more/JJR important/JJ facts/NNS ./. Change/NNP of/IN climate/NN must/MD have/VB had/VBD a/DT powerful/JJ influence/NN on/IN migration/NN ./. A/DT region/NN now/RB impassable/JJ to/TO certain/JJ organisms/NNS from/IN the/DT nature/NN of/IN its/PRP$ climate/NN ,/, might/MD have/VB been/VBN a/DT high/JJ road/NN for/IN migration/NN ,/, when/WRB the/DT climate/NN was/VBD different/JJ ./. I/PRP shall/MD ,/, however/RB ,/, presently/RB have/VBP to/TO discuss/VB this/DT branch/NN of/IN the/DT subject/NN in/IN some/DT detail/NN ./. Changes/NNS of/IN level/NN in/IN the/DT land/NN must/MD also/RB have/VBP been/VBN highly/RB influential/JJ :/: a/DT narrow/JJ isthmus/NN now/RB separates/VBZ two/CD marine/NN faunas/NNS ;/: submerge/VB it/PRP ,/, or/CC let/VB it/PRP formerly/RB have/VBP been/VBN submerged/VBN ,/, and/CC the/DT two/CD faunas/NNS will/MD now/RB blend/NN together/RB ,/, or/CC may/MD formerly/RB have/VBP blended/JJ ./. Where/WRB the/DT sea/NN now/RB extends/VBZ ,/, land/NN may/MD at/IN a/DT former/JJ period/NN have/VBP connected/VBN islands/NNS or/CC possibly/RB even/RB continents/NNS together/RB ,/, and/CC thus/RB have/VBP allowed/VBN terrestrial/JJ productions/NNS to/TO pass/VB from/IN one/CD to/TO the/DT other/JJ No/DT geologist/NN disputes/NNS that/IN great/JJ mutations/NNS of/IN level/NN have/VBP occurred/VBD within/IN the/DT period/NN of/IN existing/VBG organisms/NNS ./. Edward/NNP Forbes/NNP insisted/VBD that/IN all/DT the/DT islands/NNS in/IN the/DT Atlantic/NNP must/MD have/VB been/VBN recently/RB connected/VBN with/IN Europe/NNP or/CC Africa/NNP ,/, and/CC Europe/NNP likewise/RB with/IN America/NNP ./. Other/JJ authors/NNS have/VBP thus/RB hypothetically/RB bridged/VBN over/IN every/DT ocean/NN ,/, and/CC united/VBN almost/RB every/DT island/NN with/IN some/DT mainland/NN ./. If/IN indeed/RB the/DT arguments/NNS used/VBN by/IN Forbes/NNP are/VBP to/TO be/VB trusted/VBN ,/, it/PRP must/MD be/VB admitted/VBD that/IN scarcely/RB a/DT single/JJ island/NN exists/VBZ which/WDT has/VBZ not/RB recently/RB been/VBN united/VBN to/TO some/DT continent/NN ./. This/DT view/NN cuts/NNS the/DT Gordian/NNP knot/NN of/IN the/DT dispersal/NN of/IN the/DT same/JJ species/NN to/TO the/DT more/JJR distant/JJ points/NNS ,/, and/CC removes/VBZ many/JJ a/DT difficulty/NN ;/: but/CC to/TO the/DT best/JJS of/IN my/PRP$ judgment/NN we/PRP are/VBP not/RB authorised/VBN in/IN admitting/VBG such/JJ enormous/JJ geographical/JJ changes/NNS within/IN the/DT period/NN of/IN existing/VBG species/NN ./. It/PRP seems/VBZ to/TO me/PRP that/IN we/PRP have/VBP abundant/JJ evidence/NN of/IN great/JJ oscillations/NNS in/IN the/DT level/NN of/IN the/DT land/NN or/CC sea/NN ;/: but/CC not/RB of/IN such/JJ vast/JJ change/NN in/IN the/DT position/NN and/CC extension/NN of/IN our/PRP$ continents/NNS ,/, as/IN to/TO have/VB united/VBN them/PRP within/IN the/DT recent/JJ period/NN to/TO each/DT other/JJ and/CC to/TO the/DT several/JJ intervening/VBG oceanic/JJ islands/NNS ./. I/PRP freely/RB admit/VB the/DT former/JJ existence/NN of/IN many/JJ islands/NNS ,/, now/RB buried/VBN beneath/IN the/DT sea/NN ,/, which/WDT may/MD have/VB served/VBN as/IN halting/VBG places/NNS for/IN plants/NNS and/CC for/IN many/JJ animals/NNS during/IN their/PRP$ migration/NN ./. In/IN the/DT coral/JJ producing/VBG oceans/NNS such/JJ sunken/JJ islands/NNS are/VBP now/RB marked/VBN by/IN rings/NNS of/IN coral/JJ or/CC atolls/NNS standing/VBG over/IN them/PRP ./. Whenever/WRB it/PRP is/VBZ fully/RB admitted/VBD ,/, as/IN it/PRP will/MD some/DT day/NN be/VB ,/, that/IN each/DT species/NN has/VBZ proceeded/VBN from/IN a/DT single/JJ birthplace/NN ,/, and/CC when/WRB in/IN the/DT course/NN of/IN time/NN we/PRP know/VB something/NN definite/JJ about/IN the/DT means/VBZ of/IN distribution/NN ,/, we/PRP shall/MD be/VB enabled/VBD to/TO speculate/VB with/IN security/NN on/IN the/DT former/JJ extension/NN of/IN the/DT land/NN ./. But/CC I/PRP do/VBP not/RB believe/VBP that/IN it/PRP will/MD ever/RB be/VB proved/VBD that/IN within/IN the/DT recent/JJ period/NN most/RBS of/IN our/PRP$ continents/NNS which/WDT now/RB stand/VB quite/RB separate/JJ have/VBP been/VBN continuously/RB ,/, or/CC almost/RB continuously/RB united/VBN with/IN each/DT other/JJ ,/, and/CC with/IN the/DT many/JJ existing/VBG oceanic/JJ islands/NNS ./. Several/JJ facts/NNS in/IN distribution/NN ,/, such/JJ as/IN the/DT great/JJ difference/NN in/IN the/DT marine/NN faunas/NNS on/IN the/DT opposite/JJ sides/NNS of/IN almost/RB every/DT continent/NN ,/, the/DT close/VB relation/NN of/IN the/DT tertiary/JJ inhabitants/NNS of/IN several/JJ lands/NNS and/CC even/RB seas/NNS to/TO their/PRP$ present/JJ inhabitants/NNS ,/, the/DT degree/NN of/IN affinity/NN between/IN the/DT mammals/NNS inhabiting/VBG islands/NNS with/IN those/DT of/IN the/DT nearest/JJS continent/NN ,/, being/VBG in/IN part/NN determined/VBN (/( as/IN we/PRP shall/MD hereafter/RB see/VB )/SYM by/IN the/DT depth/NN of/IN the/DT intervening/VBG ocean/NN ,/, these/DT and/CC other/JJ such/JJ facts/NNS are/VBP opposed/VBN to/TO the/DT admission/NN of/IN such/JJ prodigious/JJ geographical/JJ revolutions/NNS within/IN the/DT recent/JJ period/NN ,/, as/IN are/VBP necessary/JJ on/IN the/DT view/NN advanced/VBD by/IN Forbes/NNP and/CC admitted/VBD by/IN his/PRP$ followers/NNS ./. The/DT nature/NN and/CC relative/JJ proportions/NNS of/IN the/DT inhabitants/NNS of/IN oceanic/JJ islands/NNS are/VBP likewise/RB opposed/VBN to/TO the/DT belief/NN of/IN their/PRP$ former/JJ continuity/NN with/IN continents/NNS ./. Nor/CC does/VBZ the/DT almost/RB universally/RB volcanic/JJ composition/NN of/IN such/JJ islands/NNS favour/NN the/DT admission/NN that/IN they/PRP are/VBP the/DT wrecks/NNS of/IN sunken/JJ continents/NNS ;/: if/IN they/PRP had/VBD originally/RB existed/VBD as/IN continental/JJ mountain/NN ranges/NNS ,/, some/DT at/IN least/JJS of/IN the/DT islands/NNS would/MD have/VB been/VBN formed/VBN ,/, like/IN other/JJ mountain/NN summits/NNS ,/, of/IN granite/NN ,/, metamorphic/JJ schists/NNS ,/, old/JJ fossiliferous/JJ and/CC other/JJ rocks/NNS ,/, instead/RB of/IN consisting/VBG of/IN mere/JJ piles/NNS of/IN volcanic/JJ matter/NN ./. I/PRP must/MD now/RB say/VBP a/DT few/JJ words/NNS on/IN what/WP are/VBP called/VBN accidental/JJ means/VBZ ,/, but/CC which/WDT more/JJR properly/RB should/MD be/VB called/VBN occasional/JJ means/VBZ of/IN distribution/NN ./. I/PRP shall/MD here/RB confine/VB myself/PRP to/TO plants/NNS ./. In/IN botanical/JJ works/NNS ,/, this/DT or/CC that/IN plant/NN is/VBZ often/RB stated/VBN to/TO be/VB ill/JJ adapted/VBN for/IN wide/JJ dissemination/NN ;/: but/CC the/DT greater/JJR or/CC less/JJR facilities/NNS for/IN transport/NN across/IN the/DT sea/NN may/MD be/VB said/VBD to/TO be/VB almost/RB wholly/RB unknown/JJ ./. Until/IN I/PRP tried/VBD ,/, with/IN Mr/NNP ./. Berkeley's/NNP aid/NN ,/, a/DT few/JJ experiments/NNS ,/, it/PRP was/VBD not/RB even/RB known/VBN how/WRB far/RB seeds/NNS could/MD resist/VB the/DT injurious/JJ action/NN of/IN sea/NN water/NN ./. To/TO my/PRP$ surprise/NN I/PRP found/VBD that/IN out/IN of/IN 87/CD kinds/NNS ,/, 64/CD germinated/JJ after/IN an/DT immersion/NN of/IN 28/CD days/NNS ,/, and/CC a/DT few/JJ survived/VBD an/DT immersion/NN of/IN 137/CD days/NNS ./. It/PRP deserves/VBZ notice/NN that/IN certain/JJ orders/NNS were/VBD far/RB more/JJR injured/VBN than/IN others/NNS :/: nine/CD leguminosae/NN were/VBD tried/VBD ,/, and/CC ,/, with/IN one/CD exception/NN ,/, they/PRP resisted/VBN the/DT salt/NN water/NN badly/RB ;/: seven/CD species/NN of/IN the/DT allied/VBN orders/NNS ,/, Hydrophyllaceae/NNP and/CC Polemoniacae/NNP ,/, were/VBD all/DT killed/VBN by/IN a/DT month's/NNS immersion/NN ./. For/IN convenience'/NN sake/NN I/PRP chiefly/RB tried/VBD small/JJ seeds/NNS without/IN the/DT capsule/NN or/CC fruit/NN ;/: and/CC as/IN all/DT of/IN these/DT sank/VBD in/IN a/DT few/JJ days/NNS they/PRP could/MD not/RB have/VBP been/VBN floated/VBD across/IN wide/JJ spaces/NNS of/IN the/DT sea/NN ,/, whether/IN or/CC not/RB they/PRP were/VBD injured/VBN by/IN the/DT salt/NN water/NN ./. Afterwards/RB I/PRP tried/VBD some/DT larger/JJR fruits/NNS ,/, capsules/NNS ,/, &c/NN ./. ,/, and/CC some/DT of/IN these/DT floated/VBD for/IN a/DT long/JJ time/NN ./. It/PRP is/VBZ well/RB known/VBN what/WP a/DT difference/NN there/EX is/VBZ in/IN the/DT buoyancy/NN of/IN green/JJ and/CC seasoned/JJ timber/NN ;/: and/CC it/PRP occurred/VBD to/TO me/PRP that/IN floods/NNS would/MD often/RB wash/NN into/IN the/DT sea/NN dried/VBN plants/NNS or/CC branches/NNS with/IN seed/NN capsules/NNS or/CC fruit/NN attached/VBN to/TO them/PRP ./. Hence/RB I/PRP was/VBD led/VBN to/TO dry/JJ the/DT stems/VBZ and/CC branches/NNS of/IN 94/CD plants/NNS with/IN ripe/JJ fruit/NN ,/, and/CC to/TO place/NN them/PRP on/IN sea/NN water/NN ./. The/DT majority/NN sank/VBD rapidly/RB ,/, but/CC some/DT which/WDT ,/, whilst/NN green/JJ ,/, floated/VBD for/IN a/DT short/JJ time/NN ,/, when/WRB dried/VBN floated/VBD much/JJ longer/RB ;/: for/IN instance/NN ,/, ripe/JJ hazel/JJ nuts/NNS sank/VBD immediately/RB ,/, but/CC when/WRB dried/VBN they/PRP floated/VBD for/IN 90/CD days/NNS ,/, and/CC afterwards/RB when/WRB planted/VBN germinated/JJ ;/: an/DT asparagus/NN plant/NN with/IN ripe/JJ berries/NNS floated/VBD for/IN 23/CD days/NNS ,/, when/WRB dried/VBN it/PRP floated/VBD for/IN 85/NN days/NNS ,/, and/CC the/DT seeds/NNS afterwards/RB germinated/JJ ;/: the/DT ripe/JJ seeds/NNS of/IN Helosciadium/NNP sank/VBD in/IN two/CD days/NNS ,/, when/WRB dried/VBN they/PRP floated/VBD for/IN above/IN 90/CD days/NNS ,/, and/CC afterwards/RB germinated/JJ ./. 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Hence/RB it/PRP has/VBZ come/VB ,/, that/IN when/WRB we/PRP compare/VB the/DT now/RB living/VBG productions/NNS of/IN the/DT temperate/JJ regions/NNS of/IN the/DT New/NNP and/CC Old/NNP Worlds/NNPS ,/, we/PRP find/VB very/RB few/JJ identical/JJ species/NN (/( though/IN Asa/NNP Gray/NNP has/VBZ lately/RB shown/VBN that/IN more/JJR plants/NNS are/VBP identical/JJ than/IN was/VBD formerly/RB supposed/VBN )/SYM ,/, but/CC we/PRP find/VB in/IN every/DT great/JJ class/NN many/JJ forms/NNS ,/, which/WDT some/DT naturalists/NNS rank/NN as/IN geographical/JJ races/NNS ,/, and/CC others/NNS as/IN distinct/JJ species/NN ;/: and/CC a/DT host/NN of/IN closely/RB allied/VBN or/CC representative/NN forms/NNS which/WDT are/VBP ranked/VBD by/IN all/DT naturalists/NNS as/IN specifically/RB distinct/JJ ./. As/IN on/IN the/DT land/NN ,/, so/RB in/IN the/DT waters/NNS of/IN the/DT sea/NN ,/, a/DT slow/JJ southern/JJ migration/NN of/IN a/DT marine/NN fauna/NNS ,/, which/WDT ,/, during/IN the/DT Pliocene/NNP or/CC even/RB a/DT somewhat/RB earlier/RBR period/NN ,/, was/VBD nearly/RB uniform/NN along/IN the/DT continuous/JJ shores/NNS of/IN the/DT Polar/NNP Circle/NNP ,/, will/MD account/NN ,/, on/IN the/DT theory/NN of/IN modification/NN ,/, for/IN many/JJ closely/RB allied/VBN forms/NNS now/RB living/VBG in/IN marine/NN areas/NNS completely/RB sundered/VBN ./. Thus/RB ,/, I/PRP think/VBP ,/, we/PRP can/MD understand/VB the/DT presence/NN of/IN some/DT closely/RB allied/VBN ,/, still/RB existing/VBG and/CC extinct/JJ tertiary/JJ forms/NNS ,/, on/IN the/DT eastern/JJ and/CC western/JJ shores/NNS of/IN temperate/JJ North/NNP America/NNP ;/: and/CC the/DT still/RB more/JJR striking/JJ fact/NN of/IN many/JJ closely/RB allied/VBN crustaceans/NNS (/( as/IN described/VBN in/IN Dana's/NNP admirable/JJ work/NN )/SYM ,/, some/DT fish/NN and/CC other/JJ marine/NN animals/NNS ,/, inhabiting/VBG the/DT Mediterranean/NNP and/CC the/DT seas/NNS of/IN Japan/NNP ,/, these/DT two/CD areas/NNS being/VBG now/RB completely/RB separated/VBN by/IN the/DT breadth/NN of/IN a/DT whole/JJ continent/NN and/CC by/IN wide/JJ spaces/NNS of/IN ocean/NN ./. These/DT cases/NNS of/IN close/VB relationship/NN in/IN species/NN either/DT now/RB or/CC formerly/RB inhabiting/VBG the/DT seas/NNS on/IN the/DT eastern/JJ and/CC western/JJ shores/NNS of/IN North/NNP America/NNP ,/, the/DT Mediterranean/NNP and/CC Japan/NNP ,/, and/CC the/DT temperate/JJ lands/NNS of/IN North/NNP America/NNP and/CC Europe/NNP ,/, are/VBP inexplicable/JJ on/IN the/DT theory/NN of/IN creation/NN ./. We/PRP cannot/MD maintain/VB that/IN such/JJ species/NN have/VBP been/VBN created/VBN alike/RB ,/, in/IN correspondence/NN with/IN the/DT nearly/RB similar/JJ physical/JJ conditions/NNS of/IN the/DT areas/NNS ;/: for/IN if/IN we/PRP compare/VB ,/, for/IN instance/NN ,/, certain/JJ parts/NNS of/IN South/NNP America/NNP with/IN parts/NNS of/IN South/NNP Africa/NNP or/CC Australia/NNP ,/, we/PRP see/VB countries/NNS closely/RB similar/JJ in/IN all/DT their/PRP$ physical/JJ conditions/NNS ,/, with/IN their/PRP$ inhabitants/NNS utterly/RB dissimilar/JJ ./. Alternate/JJ Glacial/NNP Periods/NNS in/IN the/DT North/NNP and/CC South/NNP But/CC we/PRP must/MD return/NN to/TO our/PRP$ more/JJR immediate/JJ subject/NN ./. I/PRP am/VBP convinced/VBN that/IN Forbes's/NNP view/NN may/MD be/VB largely/RB extended/VBN ./. In/IN Europe/NNP we/PRP meet/VB with/IN the/DT plainest/JJS evidence/NN of/IN the/DT Glacial/NNP period/NN ,/, from/IN the/DT western/JJ shores/NNS of/IN Britain/NNP to/TO the/DT Oural/NNP range/NN ,/, and/CC southward/RB to/TO the/DT Pyrenees/NNP ./. We/PRP may/MD infer/VB from/IN the/DT frozen/VBN mammals/NNS and/CC nature/NN of/IN the/DT mountain/NN vegetation/NN ,/, that/IN Siberia/NNP was/VBD similarly/RB affected/VBN ./. In/IN the/DT Lebanon/NNP ,/, according/VBG to/TO Dr/NNP ./. Hooker/NNP ,/, perpetual/JJ snow/NN formerly/RB covered/VBN the/DT central/JJ axis/NN ,/, and/CC fed/VBN glaciers/NNS which/WDT rolled/VBD 400/CD feet/NNS down/RB the/DT valleys/NNS ./. The/DT same/JJ observer/NN has/VBZ recently/RB found/VBD great/JJ moraines/NNS at/IN a/DT low/JJ level/NN on/IN the/DT Atlas/NNP range/NN in/IN N/NN ./. Africa/NNP ./. Along/IN the/DT Himalaya/NNP ,/, at/IN points/NNS 900/CD miles/NNS apart/RB ,/, glaciers/NNS have/VBP left/VBN the/DT marks/NNS of/IN their/PRP$ former/JJ low/JJ descent/NN ;/: and/CC in/IN Sikkim/NNP ,/, Dr/NNP ./. Hooker/NNP saw/VBD maize/VB growing/VBG on/IN ancient/JJ and/CC gigantic/JJ moraines/NNS ./. Southward/NNP of/IN the/DT Asiatic/JJ continent/NN ,/, on/IN the/DT opposite/JJ side/NN of/IN the/DT equator/NN ,/, we/PRP know/VB ,/, from/IN the/DT excellent/JJ researches/VBZ of/IN Dr/NNP ./. J/NNP ./. Haast/NNP and/CC Dr/NNP ./. Hector/NNP ,/, that/IN in/IN New/NNP Zealand/NNP immense/JJ glaciers/NNS formerly/RB descended/VBD to/TO a/DT low/JJ level/NN ;/: and/CC the/DT same/JJ plants/NNS found/VBD by/IN Dr/NNP ./. Hooker/NNP on/IN widely/RB separated/VBN mountains/NNS in/IN this/DT island/NN tell/VB the/DT same/JJ story/NN of/IN a/DT former/JJ cold/JJ period/NN ./. From/IN facts/NNS communicated/VBN to/TO me/PRP by/IN the/DT Rev/NNP ./. W/NNP ./. B/NNP ./. Clarke/NNP ,/, it/PRP appears/VBZ also/RB that/IN there/EX are/VBP traces/NNS of/IN former/JJ glacial/JJ action/NN on/IN the/DT mountains/NNS of/IN the/DT south/RB eastern/JJ corner/NN of/IN Australia/NNP ./. Looking/VBG to/TO America/NNP ;/: in/IN the/DT northern/JJ half/NN ,/, ice/NN borne/VBN fragments/NNS of/IN rock/NN have/VBP been/VBN observed/VBN on/IN the/DT eastern/JJ side/NN of/IN the/DT continent/NN ,/, as/IN far/RB south/RB as/IN lat/NN ./. 36/CD 37/CD ,/, and/CC on/IN the/DT shores/NNS of/IN the/DT Pacific/NNP ,/, where/WRB the/DT climate/NN is/VBZ now/RB so/RB different/JJ ,/, as/IN far/RB south/RB as/IN lat/NN ./. 46/CD ./. Erratic/NNP boulders/NNS have/VBP ,/, also/RB ,/, been/VBN noticed/VBD on/IN the/DT Rocky/NNP Mountains/NNPS ./. In/IN the/DT Cordillera/NNP of/IN South/NNP America/NNP ,/, nearly/RB under/IN the/DT equator/NN ,/, glaciers/NNS once/RB extended/VBN far/RB below/IN their/PRP$ present/JJ level/NN ./. In/IN Central/NNP Chile/NNP I/PRP examined/VBD a/DT vast/JJ mound/NN of/IN detritus/JJ with/IN great/JJ boulders/NNS ,/, crossing/VBG the/DT Portillo/NNP valley/NN ,/, which/WDT there/EX can/MD hardly/RB be/VB a/DT doubt/NN once/RB formed/VBN a/DT huge/JJ moraine/NN ;/: and/CC Mr/NNP ./. D/NN ./. Forbes/NNP informs/VBZ me/PRP that/IN he/PRP found/VBD in/IN various/JJ parts/NNS of/IN the/DT Cordillera/NNP ,/, from/IN lat/NN ./. 13/CD deg/NN ./. to/TO 30/CD deg/NN ./. S/NNP ./. ,/, at/IN about/IN the/DT height/NN of/IN 19/CD ,/, 000/CD feet/NNS ,/, deeply/RB furrowed/JJ rocks/NNS ,/, resembling/VBG those/DT with/IN which/WDT he/PRP was/VBD familiar/JJ in/IN Norway/NNP ,/, and/CC likewise/RB great/JJ masses/NNS of/IN detritus/JJ ,/, including/VBG grooved/VBN pebbles/NNS ./. Along/IN this/DT whole/JJ space/NN of/IN the/DT Cordillera/NNP true/JJ glaciers/NNS do/VBP not/RB exist/VB even/RB at/IN much/JJ more/JJR considerable/JJ heights/NNS ./. Farther/RB south/RB on/IN both/DT sides/NNS of/IN the/DT continent/NN ,/, from/IN lat/NN ./. 41/CD deg/NN ./. to/TO the/DT southernmost/JJ extremity/NN ,/, we/PRP have/VBP the/DT clearest/JJS evidence/NN of/IN former/JJ glacial/JJ action/NN ,/, in/IN numerous/JJ immense/JJ boulders/NNS transported/VBN far/RB from/IN their/PRP$ parent/NN source/NN ./. From/IN these/DT several/JJ facts/NNS ,/, namely/RB from/IN the/DT glacial/JJ action/NN having/VBG extended/VBN all/DT round/NN the/DT northern/JJ and/CC southern/JJ hemispheres/NNS from/IN the/DT period/NN having/VBG been/VBN in/IN a/DT geological/JJ sense/NN recent/JJ in/IN both/DT hemispheres/NNS from/IN its/PRP$ having/VBG lasted/VBD in/IN both/DT during/IN a/DT great/JJ length/NN of/IN time/NN ,/, as/IN may/MD be/VB inferred/VBD from/IN the/DT amount/NN of/IN work/NN affected/VBN and/CC lastly/RB from/IN glaciers/NNS having/VBG recently/RB descended/VBD to/TO a/DT low/JJ level/NN along/IN the/DT whole/JJ line/NN of/IN the/DT Cordillera/NNP ,/, it/PRP at/IN one/CD time/NN appeared/VBD to/TO me/PRP that/IN we/PRP could/MD not/RB avoid/VB the/DT conclusion/NN that/IN the/DT temperature/NN of/IN the/DT whole/JJ world/NN had/VBD been/VBN simultaneously/RB lowered/VBD during/IN the/DT Glacial/NNP period/NN ./. But/CC now/RB Mr/NNP ./. Croll/NNP ,/, in/IN a/DT series/NN of/IN admirable/JJ memoirs/NNS ,/, has/VBZ attempted/VBN to/TO show/NN that/IN a/DT glacial/JJ condition/NN of/IN climate/NN is/VBZ the/DT result/NN of/IN various/JJ physical/JJ causes/NNS ,/, brought/VBN into/IN operation/NN by/IN an/DT increase/NN in/IN the/DT eccentricity/NN of/IN the/DT earth's/NNS orbit/NN ./. All/DT these/DT causes/NNS tend/VBP towards/IN the/DT same/JJ end/NN ;/: but/CC the/DT most/RBS powerful/JJ appears/VBZ to/TO be/VB the/DT indirect/JJ influence/NN of/IN the/DT eccentricity/NN of/IN the/DT orbit/NN upon/IN oceanic/JJ currents/NNS ./. According/VBG to/TO Mr/NNP ./. Croll/NNP ,/, cold/JJ periods/NNS regularly/RB occur/VB every/DT ten/CD or/CC fifteen/CD thousand/CD years/NNS ;/: and/CC these/DT at/IN long/JJ intervals/NNS are/VBP extremely/RB severe/JJ ,/, owing/JJ to/TO certain/JJ contingencies/NNS ,/, of/IN which/WDT the/DT most/RBS important/JJ ,/, as/IN Sir/NNP C/NN ./. Lyell/NNP has/VBZ shown/VBN ,/, is/VBZ the/DT relative/JJ position/NN of/IN the/DT land/NN and/CC water/NN ./. Mr/NNP ./. Croll/NNP believes/VBZ that/IN the/DT last/JJ great/JJ Glacial/NNP period/NN occurred/VBD about/IN 240/CD ,/, 000/CD years/NNS ago/RB ,/, and/CC endured/VBD with/IN slight/JJ alterations/NNS of/IN climate/NN for/IN about/IN 160/CD ,/, 000/CD years/NNS ./. With/IN respect/NN to/TO more/JJR ancient/JJ Glacial/NNP periods/NNS ,/, several/JJ geologists/NNS are/VBP convinced/VBN from/IN direct/JJ evidence/NN that/IN such/JJ occurred/VBD during/IN the/DT Miocene/NNP and/CC Eocene/NNP formations/NNS ,/, not/RB to/TO mention/VB still/RB more/JJR ancient/JJ formations/NNS ./. But/CC the/DT most/RBS important/JJ result/NN for/IN us/PRP ,/, arrived/VBD at/IN by/IN Mr/NNP ./. Croll/NNP ,/, is/VBZ that/IN whenever/WRB the/DT northern/JJ hemisphere/NN passes/VBZ through/IN a/DT cold/JJ period/NN the/DT temperature/NN of/IN the/DT southern/JJ hemisphere/NN is/VBZ actually/RB raised/VBN ,/, with/IN the/DT winters/NNS rendered/VBN much/JJ milder/JJR ,/, chiefly/RB through/IN changes/NNS in/IN the/DT direction/NN of/IN the/DT ocean/NN currents/NNS ./. So/RB conversely/RB it/PRP will/MD be/VB with/IN the/DT northern/JJ hemisphere/NN ,/, whilst/NN the/DT southern/JJ passes/VBZ through/IN a/DT Glacial/NNP period/NN ./. This/DT conclusion/NN throws/VBZ so/RB much/JJ light/NN on/IN geographical/JJ distribution/NN that/IN I/PRP am/VBP strongly/RB inclined/VBN to/TO trust/NN in/IN it/PRP ;/: but/CC I/PRP will/MD first/JJ give/VB the/DT facts/NNS ,/, which/WDT demand/NN an/DT explanation/NN ./. In/IN South/NNP America/NNP ,/, Dr/NNP ./. Hooker/NNP has/VBZ shown/VBN that/IN besides/IN many/JJ closely/RB allied/VBN species/NN ,/, between/IN forty/CD and/CC fifty/CD of/IN the/DT flowering/NN plants/NNS of/IN Tierra/NNP del/NNP Fuego/NNP ,/, forming/VBG no/DT inconsiderable/JJ part/NN of/IN its/PRP$ scanty/JJ flora/NNS ,/, are/VBP common/JJ to/TO North/NNP America/NNP and/CC Europe/NNP ,/, enormously/RB remote/JJ as/IN these/DT areas/NNS in/IN opposite/JJ hemispheres/NNS are/VBP from/IN each/DT other/JJ ./. On/IN the/DT lofty/JJ mountains/NNS of/IN equatorial/JJ America/NNP a/DT host/NN of/IN peculiar/JJ species/NN belonging/VBG to/TO European/JJ genera/NN occur/VB ./. On/IN the/DT Organ/NN mountains/NNS of/IN Brazil/NNP ,/, some/DT few/JJ temperate/JJ European/JJ ,/, some/DT Antarctic/NNP ,/, and/CC some/DT Andean/JJ genera/NN were/VBD found/VBD by/IN Gardner/NNP ,/, which/WDT do/VBP not/RB exist/VB in/IN the/DT low/JJ intervening/VBG hot/JJ countries/NNS ./. On/IN the/DT Silla/NNP of/IN Caraccas/NNP ,/, the/DT illustrious/JJ Humboldt/NNP long/JJ ago/RB found/VBD species/NN belonging/VBG to/TO genera/NN characteristic/JJ of/IN the/DT Cordillera/NNP ./. In/IN Africa/NNP ,/, several/JJ forms/NNS characteristic/JJ of/IN Europe/NNP and/CC some/DT few/JJ representatives/NNS of/IN the/DT flora/NNS of/IN the/DT Cape/NNP of/IN Good/JJ Hope/NNP occur/VB in/IN the/DT mountains/NNS of/IN Abyssinia/NNP ./. At/IN the/DT Cape/NNP of/IN Good/JJ Hope/NNP a/DT very/RB few/JJ European/JJ species/NN ,/, believed/VBD not/RB to/TO have/VB been/VBN introduced/VBN by/IN man/NN ,/, and/CC on/IN the/DT mountains/NNS several/JJ representative/NN European/JJ forms/NNS are/VBP found/VBD ,/, which/WDT have/VBP not/RB been/VBN discovered/VBN in/IN the/DT intertropical/JJ parts/NNS of/IN Africa/NNP ./. Dr/NNP ./. Hooker/NNP has/VBZ also/RB lately/RB shown/VBN that/IN several/JJ of/IN the/DT plants/NNS living/VBG on/IN the/DT upper/JJ parts/NNS of/IN the/DT lofty/JJ island/NN of/IN Fernando/NNP Po/NNP and/CC on/IN the/DT neighbouring/VBG Cameroon/NNP mountains/NNS ,/, in/IN the/DT Gulf/NNP of/IN Guinea/NNP ,/, are/VBP closely/RB related/VBN to/TO those/DT on/IN the/DT mountains/NNS of/IN Abyssinia/NNP ,/, and/CC likewise/RB to/TO those/DT of/IN temperate/JJ Europe/NNP ./. It/PRP now/RB also/RB appears/VBZ ,/, as/IN I/PRP hear/VB from/IN Dr/NNP ./. Hooker/NNP ,/, that/IN some/DT of/IN these/DT same/JJ temperate/JJ plants/NNS have/VBP been/VBN discovered/VBN by/IN the/DT Rev/NNP ./. R/NN ./. T/NN ./. Lowe/NNP on/IN the/DT mountains/NNS of/IN the/DT Cape/NNP Verde/NNP Islands/NNPS ./. This/DT extension/NN of/IN the/DT same/JJ temperate/JJ forms/NNS ,/, almost/RB under/IN the/DT equator/NN ,/, across/IN the/DT whole/JJ continent/NN of/IN Africa/NNP and/CC to/TO the/DT mountains/NNS of/IN the/DT Cape/NNP Verde/NNP Archipelago/NNP ,/, is/VBZ one/CD of/IN the/DT most/RBS astonishing/JJ facts/NNS ever/RB recorded/VBN in/IN the/DT distribution/NN of/IN plants/NNS ./. On/IN the/DT Himalaya/NNP ,/, and/CC on/IN the/DT isolated/VBN mountain/NN ranges/NNS of/IN the/DT peninsula/NN of/IN India/NNP ,/, on/IN the/DT heights/NNS of/IN Ceylon/NNP ,/, and/CC on/IN the/DT volcanic/JJ cones/NNS of/IN Java/NNP ,/, many/JJ plants/NNS occur/VB ,/, either/DT identically/RB the/DT same/JJ or/CC representing/VBG each/DT other/JJ ,/, and/CC at/IN the/DT same/JJ time/NN representing/VBG plants/NNS of/IN Europe/NNP ,/, not/RB found/VBD in/IN the/DT intervening/VBG hot/JJ lowlands/NNS ./. A/DT list/NN of/IN the/DT genera/NN of/IN plants/NNS collected/VBN on/IN the/DT loftier/NN peaks/NNS of/IN Java/NNP ,/, raises/VBZ a/DT picture/NN of/IN a/DT collection/NN made/VBN on/IN a/DT hillock/NN in/IN Europe!/NNP Still/RB more/JJR striking/JJ is/VBZ the/DT fact/NN that/IN peculiar/JJ Australian/JJ forms/NNS are/VBP represented/VBN by/IN certain/JJ plants/NNS growing/VBG on/IN the/DT summits/NNS of/IN the/DT mountains/NNS of/IN Borneo/NNP ./. Some/DT of/IN these/DT Australian/JJ forms/NNS ,/, as/IN I/PRP hear/VB from/IN Dr/NNP ./. Hooker/NNP ,/, extend/VB along/IN the/DT heights/NNS of/IN the/DT peninsula/NN of/IN Malacca/NNP ,/, and/CC are/VBP thinly/RB scattered/VBN on/IN the/DT one/CD hand/NN over/IN India/NNP ,/, and/CC on/IN the/DT other/JJ hand/NN as/IN far/RB north/RB as/IN Japan/NNP ./. On/IN the/DT southern/JJ mountains/NNS of/IN Australia/NNP ,/, Dr/NNP ./. F/NN ./. Muller/NNP has/VBZ discovered/VBN several/JJ European/JJ species/NN ;/: other/JJ species/NN ,/, not/RB introduced/VBN by/IN man/NN ,/, occur/VB on/IN the/DT lowlands/NNS ;/: and/CC a/DT long/JJ list/NN can/MD be/VB given/VBN ,/, as/IN I/PRP am/VBP informed/VBN by/IN Dr/NNP ./. Hooker/NNP ,/, of/IN European/JJ genera/NN ,/, found/VBD in/IN Australia/NNP ,/, but/CC not/RB in/IN the/DT intermediate/JJ torrid/JJ regions/NNS ./. In/IN the/DT admirable/JJ Introduction/NN to/TO the/DT Flora/NNP of/IN New/NNP Zealand/NNP ,/, by/IN Dr/NNP ./. Hooker/NNP ,/, analogous/JJ and/CC striking/JJ facts/NNS are/VBP given/VBN in/IN regard/NN to/TO the/DT plants/NNS of/IN that/IN large/JJ island/NN ./. Hence/RB we/PRP see/VB that/IN certain/JJ plants/NNS growing/VBG on/IN the/DT more/JJR lofty/JJ mountains/NNS of/IN the/DT tropics/NNS in/IN all/DT parts/NNS of/IN the/DT world/NN ,/, and/CC on/IN the/DT temperate/JJ plains/NNS of/IN the/DT north/RB and/CC south/RB ,/, are/VBP either/DT the/DT same/JJ species/NN or/CC varieties/NNS of/IN the/DT same/JJ species/NN ./. It/PRP should/MD ,/, however/RB ,/, be/VB observed/VBN that/IN these/DT plants/NNS are/VBP not/RB strictly/RB arctic/JJ forms/NNS ;/: for/IN ,/, as/IN Mr/NNP ./. H/NNP ./. C/NN ./. Watson/NNP has/VBZ remarked/VBN ,/, "/" in/IN receding/VBG from/IN polar/JJ towards/IN equatorial/JJ latitudes/NNS ,/, the/DT Alpine/NNP or/CC mountain/NN floras/NNS really/RB become/VB less/JJR and/CC less/JJR Arctic/NNP ./. "/" Besides/IN these/DT identical/JJ and/CC closely/RB allied/VBN forms/NNS ,/, many/JJ species/NN inhabiting/VBG the/DT same/JJ widely/RB sundered/VBN areas/NNS ,/, belong/VB to/TO genera/NN not/RB now/RB found/VBD in/IN the/DT intermediate/JJ tropical/JJ lowlands/NNS ./. These/DT brief/JJ remarks/NNS apply/VB to/TO plants/NNS alone/RB ;/: but/CC some/DT few/JJ analogous/JJ facts/NNS could/MD be/VB given/VBN in/IN regard/NN to/TO terrestrial/JJ animals/NNS ./. In/IN marine/NN productions/NNS ,/, similar/JJ cases/NNS likewise/RB occur/VB ;/: as/IN an/DT example/NN ,/, I/PRP may/MD quote/VB a/DT statement/NN by/IN the/DT highest/JJS authority/NN ,/, Prof/NNP ./. Dana/NNP ,/, that/IN "/" It/PRP is/VBZ certainly/RB a/DT wonderful/JJ fact/NN that/IN New/NNP Zealand/NNP should/MD have/VB a/DT closer/JJR resemblance/NN in/IN its/PRP$ Crustacea/NNP to/TO Great/NNP Britain/NNP ,/, its/PRP$ antipode/NN ,/, than/IN to/TO any/DT other/JJ part/NN of/IN the/DT world/NN ./. "/" Sir/NNP J/NNP ./. 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If/IN we/PRP compare/VB ,/, for/IN instance/NN ,/, the/DT number/NN of/IN endemic/JJ landshells/NNS in/IN Madeira/NNP ,/, or/CC of/IN endemic/JJ birds/NNS in/IN the/DT Galapagos/NNP Archipelago/NNP ,/, with/IN the/DT number/NN found/VBD on/IN any/DT continent/NN ,/, and/CC then/RB compare/VB the/DT area/NN of/IN the/DT island/NN with/IN that/IN of/IN the/DT continent/NN ,/, we/PRP shall/MD see/VB that/IN this/DT is/VBZ true/JJ ./. This/DT fact/NN might/MD have/VB been/VBN theoretically/RB expected/VBN ,/, for/IN ,/, as/IN already/RB explained/VBD ,/, species/NN occasionally/RB arriving/VBG after/IN long/JJ intervals/NNS of/IN time/NN in/IN the/DT new/JJ and/CC isolated/VBN district/NN ,/, and/CC having/VBG to/TO compete/VB with/IN new/JJ associates/NNS ,/, would/MD be/VB eminently/RB liable/JJ to/TO modification/NN ,/, and/CC would/MD often/RB produce/VB groups/NNS of/IN modified/VBN descendants/NNS ./. But/CC it/PRP by/IN no/DT means/VBZ follows/VBZ that/IN ,/, because/IN in/IN an/DT island/NN nearly/RB all/DT the/DT species/NN of/IN one/CD class/NN are/VBP peculiar/JJ ,/, those/DT of/IN another/DT class/NN ,/, or/CC of/IN another/DT section/NN of/IN the/DT same/JJ class/NN ,/, are/VBP peculiar/JJ ;/: and/CC this/DT difference/NN seems/VBZ to/TO depend/VB partly/RB on/IN the/DT species/NN which/WDT are/VBP not/RB modified/VBN having/VBG immigrated/VBD in/IN a/DT body/NN ,/, so/RB that/IN their/PRP$ mutual/JJ relations/NNS have/VBP not/RB been/VBN much/JJ disturbed/VBN ;/: and/CC partly/RB on/IN the/DT frequent/JJ arrival/NN of/IN unmodified/JJ immigrants/NNS from/IN the/DT mother/NN country/NN ,/, with/IN which/WDT the/DT insular/JJ forms/NNS have/VBP intercrossed/VBN ./. It/PRP should/MD be/VB borne/VBN in/IN mind/NN that/IN the/DT offspring/NN of/IN such/JJ crosses/VBZ would/MD certainly/RB gain/NN in/IN vigour/NN ,/, so/RB that/IN even/RB an/DT occasional/JJ cross/VB would/MD produce/VB more/JJR effect/NN than/IN might/MD have/VB been/VBN anticipated/VBN ./. I/PRP will/MD give/VB a/DT few/JJ illustrations/NNS of/IN the/DT foregoing/NN remarks/NNS :/: in/IN the/DT Galapagos/NNP Islands/NNPS there/EX are/VBP 9/NN ./. 6/NN land/NN birds/NNS ;/: of/IN these/DT 21/CD (/( or/CC perhaps/RB 93/CD )/SYM are/VBP peculiar/JJ ,/, whereas/IN of/IN the/DT 11/CD marine/NN birds/NNS only/RB 2/CD are/VBP peculiar/JJ ;/: and/CC it/PRP is/VBZ obvious/JJ that/IN marine/NN birds/NNS could/MD arrive/VB at/IN these/DT islands/NNS much/JJ more/JJR easily/RB and/CC frequently/RB than/IN land/NN birds/NNS ./. Bermuda/NNP ,/, on/IN the/DT other/JJ hand/NN ,/, which/WDT lies/VBZ at/IN about/IN the/DT same/JJ distance/NN from/IN North/NNP America/NNP as/IN the/DT Galapagos/NNP Islands/NNPS do/VBP from/IN South/NNP America/NNP ,/, and/CC which/WDT has/VBZ a/DT very/RB peculiar/JJ soil/NN ,/, does/VBZ not/RB possess/VBP a/DT single/JJ endemic/JJ landbird/NN ,/, and/CC we/PRP know/VB from/IN Mr/NNP ./. J/NNP ./. M/NNP ./. Jones's/NNP admirable/JJ account/NN of/IN Bermuda/NNP ,/, that/IN very/RB many/JJ North/NNP American/NNP birds/NNS occasionally/RB or/CC even/RB frequently/RB visit/NN this/DT ,/, island/NN ./. Almost/RB every/DT year/NN ,/, as/IN I/PRP am/VBP informed/VBN by/IN Mr/NNP ./. E/NN ./. V/NN ./. Harcourt/NNP ,/, many/JJ European/JJ and/CC African/JJ birds/NNS are/VBP blown/VBN to/TO Madeira/NNP ;/: this/DT island/NN is/VBZ inhabited/VBN by/IN 99/NN kinds/NNS of/IN which/WDT one/CD alone/RB is/VBZ peculiar/JJ ,/, though/IN very/RB closely/RB related/VBN to/TO a/DT European/JJ form/NN ;/: and/CC three/CD or/CC four/CD other/JJ species/NN are/VBP confined/VBN to/TO this/DT island/NN and/CC to/TO the/DT Canaries/NNP ./. So/RB that/IN the/DT islands/NNS of/IN Bermuda/NNP and/CC Madeira/NNP have/VBP been/VBN stocked/VBN from/IN the/DT neighbouring/VBG continents/NNS with/IN birds/NNS ,/, which/WDT for/IN long/JJ ages/NNS have/VBP there/EX struggled/VBD together/RB ,/, and/CC have/VBP become/VB mutually/RB co/NN adapted/VBN ./. Hence/RB when/WRB settled/VBD in/IN their/PRP$ new/JJ homes/NNS ,/, each/DT kind/NN will/MD have/VB been/VBN kept/VBD by/IN the/DT others/NNS to/TO its/PRP$ proper/JJ place/NN and/CC habits/NNS ,/, and/CC will/MD consequently/RB have/VBP been/VBN but/CC little/JJ liable/JJ to/TO modification/NN ./. Any/DT tendency/NN to/TO modification/NN will/MD also/RB have/VBP been/VBN checked/VBN by/IN intercrossing/VBG with/IN the/DT unmodified/JJ immigrants/NNS ,/, often/RB arriving/VBG from/IN the/DT mother/NN country/NN ./. Madeira/NNP again/RB is/VBZ inhabited/VBN by/IN a/DT wonderful/JJ number/NN of/IN peculiar/JJ land/NN shells/NNS ,/, whereas/IN not/RB one/CD species/NN of/IN sea/NN shell/NN is/VBZ peculiar/JJ to/TO its/PRP$ shores/NNS :/: now/RB ,/, though/IN we/PRP do/VBP not/RB know/VB how/WRB seashells/NNS are/VBP dispersed/VBN ,/, yet/RB we/PRP can/MD see/VB that/IN their/PRP$ eggs/NNS or/CC larvae/NNS ,/, perhaps/RB attached/VBN to/TO seaweed/NN or/CC floating/VBG timber/NN ,/, or/CC to/TO the/DT feet/NNS of/IN wading/VBG birds/NNS ,/, might/MD be/VB transported/VBN across/IN three/CD or/CC four/CD hundred/CD miles/NNS of/IN open/JJ sea/NN far/RB more/JJR easily/RB than/IN land/NN shells/NNS ./. The/DT different/JJ orders/NNS of/IN insects/NNS inhabiting/VBG Madeira/NNP present/JJ nearly/RB parallel/JJ cases/NNS ./. Oceanic/NNP islands/NNS are/VBP sometimes/RB deficient/JJ in/IN animals/NNS of/IN certain/JJ whole/JJ classes/NNS ,/, and/CC their/PRP$ places/NNS are/VBP occupied/VBN by/IN other/JJ classes/NNS ;/: thus/RB in/IN the/DT Galapagos/NNP Islands/NNPS reptiles/NNS ,/, and/CC in/IN New/NNP Zealand/NNP gigantic/JJ wingless/JJ birds/NNS ,/, take/VB ,/, or/CC recently/RB took/VBD ,/, the/DT place/NN of/IN mammals/NNS ./. Although/IN New/NNP Zealand/NNP is/VBZ here/RB spoken/VBN of/IN as/IN an/DT oceanic/JJ island/NN ,/, it/PRP is/VBZ in/IN some/DT degree/NN doubtful/JJ whether/IN it/PRP should/MD be/VB so/RB ranked/VBD ;/: it/PRP is/VBZ of/IN large/JJ size/NN ,/, and/CC is/VBZ not/RB separated/VBN from/IN Australia/NNP by/IN a/DT profoundly/RB deep/JJ sea/NN ;/: from/IN its/PRP$ geological/JJ character/NN and/CC the/DT direction/NN of/IN its/PRP$ mountain/NN ranges/NNS ,/, the/DT Rev/NNP ./. W/NNP ./. B/NNP ./. Clarke/NNP has/VBZ lately/RB maintained/VBN that/IN this/DT island/NN ,/, as/IN well/RB as/IN New/NNP Caledonia/NNP ,/, should/MD be/VB considered/VBN as/IN appurtenances/NNS of/IN Australia/NNP ./. Turning/VBG to/TO plants/NNS ,/, Dr/NNP ./. Hooker/NNP has/VBZ shown/VBN that/IN in/IN the/DT Galapagos/NNP Islands/NNPS the/DT proportional/JJ numbers/NNS of/IN the/DT different/JJ orders/NNS are/VBP very/RB different/JJ from/IN what/WP they/PRP are/VBP elsewhere/RB ./. All/DT such/JJ differences/NNS in/IN number/NN ,/, and/CC the/DT absence/NN of/IN certain/JJ whole/JJ groups/NNS of/IN animals/NNS and/CC plants/NNS ,/, are/VBP generally/RB accounted/VBD for/IN by/IN supposed/VBN differences/NNS in/IN the/DT physical/JJ conditions/NNS of/IN the/DT islands/NNS ;/: but/CC this/DT explanation/NN is/VBZ not/RB a/DT little/JJ doubtful/JJ ./. Facility/NNP of/IN immigration/NN seems/VBZ to/TO have/VB been/VBN fully/RB as/IN important/JJ as/IN the/DT nature/NN of/IN the/DT conditions/NNS ./. Many/JJ remarkable/JJ little/JJ facts/NNS could/MD be/VB given/VBN with/IN respect/NN to/TO the/DT inhabitants/NNS of/IN oceanic/JJ islands/NNS ./. For/IN instance/NN ,/, in/IN certain/JJ islands/NNS not/RB tenanted/VBN by/IN a/DT single/JJ mammal/NN ,/, some/DT of/IN the/DT endemic/JJ plants/NNS have/VBP beautifully/RB hooked/VBN seeds/NNS ;/: yet/RB few/JJ relations/NNS are/VBP more/JJR manifest/JJ than/IN that/IN hooks/NNS serve/VB for/IN the/DT transportal/JJ of/IN seeds/NNS in/IN the/DT wool/NN or/CC fur/NN of/IN quadrupeds/NNS ./. But/CC a/DT hooked/VBN seed/NN might/MD be/VB carried/VBD to/TO an/DT island/NN by/IN other/JJ means/VBZ ;/: and/CC the/DT plant/NN then/RB becoming/VBG modified/VBN would/MD form/NN an/DT endemic/JJ species/NN ,/, still/RB retaining/VBG its/PRP$ hooks/NNS ,/, which/WDT would/MD form/NN a/DT useless/JJ appendage/NN like/IN the/DT shrivelled/VBN wings/NNS under/IN the/DT soldered/VBN wing/NN covers/VBZ of/IN many/JJ insular/JJ beetles/NNS ./. Again/RB ,/, islands/NNS often/RB possess/VBP trees/NNS or/CC bushes/NNS belonging/VBG to/TO orders/NNS which/WDT elsewhere/RB include/VBP only/RB herbaceous/JJ species/NN ;/: now/RB trees/NNS ,/, as/IN Alph/NNP ./. de/FW Candolle/NNP has/VBZ shown/VBN ,/, generally/RB have/VBP ,/, whatever/WDT the/DT cause/NN may/MD be/VB ,/, confined/VBN ranges/NNS ./. Hence/RB trees/NNS would/MD be/VB little/JJ likely/JJ to/TO reach/VB distant/JJ oceanic/JJ islands/NNS ;/: and/CC an/DT herbaceous/JJ plant/NN ,/, which/WDT had/VBD no/DT chance/NN of/IN successfully/RB competing/VBG with/IN the/DT many/JJ fully/RB developed/VBN trees/NNS growing/VBG on/IN a/DT continent/NN ,/, might/MD ,/, when/WRB established/VBN on/IN an/DT island/NN ,/, gain/NN an/DT advantage/NN over/IN other/JJ herbaceous/JJ plants/NNS by/IN growing/VBG taller/JJR and/CC taller/JJR and/CC overtopping/VBG them/PRP ./. In/IN this/DT case/NN ,/, natural/JJ selection/NN would/MD tend/VB to/TO add/VB to/TO the/DT stature/NN of/IN the/DT plant/NN ,/, to/TO whatever/WDT order/NN it/PRP belonged/VBD ,/, and/CC thus/RB first/JJ convert/VB it/PRP into/IN a/DT bush/NN and/CC then/RB into/IN a/DT tree/NN ./. Absence/NNP of/IN Batrachians/NNPS and/CC Terrestrial/NNP Mammals/NNP on/IN Oceanic/NNP Islands/NNPS With/IN respect/NN to/TO the/DT absence/NN of/IN whole/JJ orders/NNS of/IN animals/NNS on/IN oceanic/JJ islands/NNS ,/, Bory/NNP St/NNP ./. Vincent/NNP long/JJ ago/RB remarked/VBD that/IN batrachians/NNS (/( frogs/NNS ,/, toads/NNS ,/, newts/NNS )/SYM are/VBP never/RB found/VBD on/IN any/DT of/IN the/DT many/JJ islands/NNS with/IN which/WDT the/DT great/JJ oceans/NNS are/VBP studded/VBN ./. I/PRP have/VBP taken/VBN pains/NNS to/TO verify/VB this/DT assertion/NN ,/, and/CC have/VBP found/VBD it/PRP true/JJ ,/, with/IN the/DT exception/NN of/IN New/NNP Zealand/NNP ,/, New/NNP Caledonia/NNP ,/, the/DT Andaman/NNP Islands/NNPS ,/, and/CC perhaps/RB the/DT Solomon/NNP Islands/NNPS and/CC the/DT Seychelles/NNP ./. But/CC I/PRP have/VBP already/RB remarked/VBD that/IN it/PRP is/VBZ doubtful/JJ whether/IN New/NNP Zealand/NNP and/CC New/NNP Caledonia/NNP ought/MD to/TO be/VB classed/VBN as/IN oceanic/JJ islands/NNS ;/: and/CC this/DT is/VBZ still/RB more/JJR doubtful/JJ with/IN respect/NN to/TO the/DT Andaman/NNP and/CC Solomon/NNP groups/NNS and/CC the/DT Seychelles/NNP ./. This/DT general/JJ absence/NN of/IN frogs/NNS ,/, toads/NNS ,/, and/CC newts/NNS on/IN so/RB many/JJ true/JJ oceanic/JJ islands/NNS cannot/MD be/VB accounted/VBD for/IN by/IN their/PRP$ physical/JJ conditions/NNS :/: indeed/RB it/PRP seems/VBZ that/IN islands/NNS are/VBP peculiarly/RB fitted/VBN for/IN these/DT animals/NNS ;/: for/IN frogs/NNS have/VBP been/VBN introduced/VBN into/IN Madeira/NNP ,/, the/DT Azores/NNP ,/, and/CC Mauritius/NNP ,/, and/CC have/VBP multiplied/VBN so/RB as/IN to/TO become/VB a/DT nuisance/NN ./. But/CC as/IN these/DT animals/NNS and/CC their/PRP$ spawn/VB are/VBP immediately/RB killed/VBN (/( with/IN the/DT exception/NN ,/, as/IN far/RB as/IN known/VBN ,/, of/IN one/CD Indian/NNP species/NN )/SYM by/IN sea/NN water/NN ,/, there/EX would/MD be/VB great/JJ difficulty/NN in/IN their/PRP$ transportal/JJ across/IN the/DT sea/NN ,/, and/CC therefore/RB we/PRP can/MD see/VB why/WRB they/PRP do/VBP not/RB exist/VB on/IN strictly/RB oceanic/JJ islands/NNS ./. But/CC why/WRB ,/, on/IN the/DT theory/NN of/IN creation/NN ,/, they/PRP should/MD not/RB have/VBP been/VBN created/VBN there/EX ,/, it/PRP would/MD be/VB very/RB difficult/JJ to/TO explain/VB ./. Mammals/NNP offer/NN another/DT and/CC similar/JJ case/NN ./. I/PRP have/VBP carefully/RB searched/VBD the/DT oldest/JJS voyages/NNS ,/, and/CC have/VBP not/RB found/VBD a/DT single/JJ instance/NN ,/, free/JJ from/IN doubt/NN ,/, of/IN a/DT terrestrial/JJ mammal/NN (/( excluding/VBG domesticated/VBN animals/NNS kept/VBD by/IN the/DT natives/NNS )/SYM inhabiting/VBG an/DT island/NN situated/VBN above/IN 300/CD miles/NNS from/IN a/DT continent/NN or/CC great/JJ continental/JJ island/NN ;/: and/CC many/JJ islands/NNS situated/VBN at/IN a/DT much/JJ less/JJR distance/NN are/VBP equally/RB barren/JJ ./. The/DT Falkland/NNP Islands/NNPS ,/, which/WDT are/VBP inhabited/VBN by/IN a/DT wolf/NN like/IN fox/NN ,/, come/VB nearest/JJS to/TO an/DT exception/NN ;/: but/CC this/DT group/NN cannot/MD be/VB considered/VBN as/IN oceanic/JJ ,/, as/IN it/PRP lies/VBZ on/IN a/DT bank/NN in/IN connection/NN with/IN the/DT mainland/NN at/IN the/DT distance/NN of/IN about/IN 280/CD miles/NNS ;/: moreover/RB ,/, icebergs/NNS formerly/RB brought/VBN boulders/NNS to/TO its/PRP$ western/JJ shores/NNS ,/, and/CC they/PRP may/MD have/VB formerly/RB transported/VBN foxes/NNS ,/, as/IN now/RB frequently/RB happens/VBZ in/IN the/DT arctic/JJ regions/NNS ./. Yet/RB it/PRP cannot/MD be/VB said/VBD that/IN small/JJ islands/NNS will/MD not/RB support/NN at/IN least/JJS small/JJ mammals/NNS ,/, for/IN they/PRP occur/VB in/IN many/JJ parts/NNS of/IN the/DT world/NN on/IN very/RB small/JJ islands/NNS ,/, when/WRB lying/VBG close/VB to/TO a/DT continent/NN ;/: and/CC hardly/RB an/DT island/NN can/MD be/VB named/VBN on/IN which/WDT our/PRP$ smaller/JJR quadrupeds/NNS have/VBP not/RB become/VB naturalised/VBN and/CC greatly/RB multiplied/VBN ./. It/PRP cannot/MD be/VB said/VBD ,/, on/IN the/DT ordinary/JJ view/NN of/IN creation/NN ,/, that/IN there/EX has/VBZ not/RB been/VBN time/NN for/IN the/DT creation/NN of/IN mammals/NNS ;/: many/JJ volcanic/JJ islands/NNS are/VBP sufficiently/RB ancient/JJ ,/, as/IN shown/VBN by/IN the/DT stupendous/JJ degradation/NN which/WDT they/PRP have/VBP suffered/VBD ,/, and/CC by/IN their/PRP$ tertiary/JJ strata/NNS :/: there/EX has/VBZ also/RB been/VBN time/NN for/IN the/DT production/NN of/IN endemic/JJ species/NN belonging/VBG to/TO other/JJ classes/NNS ;/: and/CC on/IN continents/NNS it/PRP is/VBZ known/VBN that/IN new/JJ species/NN of/IN mammals/NNS appear/VB and/CC disappear/VB at/IN a/DT quicker/JJR rate/NN than/IN other/JJ and/CC lower/JJR animals/NNS ./. Although/IN terrestrial/JJ mammals/NNS do/VBP not/RB occur/VB on/IN oceanic/JJ islands/NNS ,/, aerial/JJ mammals/NNS do/VBP occur/VB on/IN almost/RB every/DT island/NN ./. New/NNP Zealand/NNP possesses/VBZ two/CD bats/NNS found/VBD nowhere/RB else/RB in/IN the/DT world/NN :/: Norfolk/NNP Island/NNP ,/, the/DT Viti/NNP Archipelago/NNP ,/, the/DT Bonin/NNP Islands/NNPS ,/, the/DT Caroline/NNP and/CC Marianne/NNP Archipelagoes/NNP ,/, and/CC Mauritius/NNP ,/, all/DT possess/VBP their/PRP$ peculiar/JJ bats/NNS ./. Why/WRB ,/, it/PRP may/MD be/VB asked/VBD ,/, has/VBZ the/DT supposed/VBN creative/JJ force/NN produced/VBN bats/NNS and/CC no/DT other/JJ mammals/NNS on/IN remote/JJ islands/NNS ?/. On/IN my/PRP$ view/NN this/DT question/NN can/MD easily/RB be/VB answered/VBD ;/: for/IN no/DT terrestrial/JJ mammal/NN can/MD be/VB transported/VBN across/IN a/DT wide/JJ space/NN of/IN sea/NN ,/, but/CC bats/NNS can/MD fly/VB across/IN ./. Bats/NNS have/VBP been/VBN seen/VBN wandering/VBG by/IN day/NN far/RB over/IN the/DT Atlantic/NNP Ocean/NNP ;/: and/CC two/CD North/NNP American/NNP species/NN either/DT regularly/RB or/CC occasionally/RB visit/NN Bermuda/NNP ,/, at/IN the/DT distance/NN of/IN 600/CD miles/NNS from/IN the/DT mainland/NN ./. I/PRP hear/VB from/IN Mr/NNP ./. Tomes/NNP ,/, who/WP has/VBZ specially/RB studied/VBN this/DT family/NN ,/, that/IN many/JJ species/NN have/VBP enormous/JJ ranges/NNS ,/, and/CC are/VBP found/VBD on/IN continents/NNS and/CC on/IN far/RB distant/JJ islands/NNS ./. Hence/RB we/PRP have/VBP only/RB to/TO suppose/VB that/IN such/JJ wandering/VBG species/NN have/VBP been/VBN modified/VBN in/IN their/PRP$ new/JJ homes/NNS in/IN relation/NN to/TO their/PRP$ new/JJ position/NN ,/, and/CC we/PRP can/MD understand/VB the/DT presence/NN of/IN endemic/JJ bats/NNS on/IN oceanic/JJ islands/NNS ,/, with/IN the/DT absence/NN of/IN all/DT other/JJ terrestrial/JJ mammals/NNS ./. Another/DT interesting/JJ relation/NN exists/VBZ ,/, namely/RB ,/, between/IN the/DT depth/NN of/IN the/DT sea/NN separating/VBG islands/NNS from/IN each/DT other/JJ or/CC from/IN the/DT nearest/JJS continent/NN ,/, and/CC the/DT degree/NN of/IN affinity/NN of/IN their/PRP$ mammalian/JJ inhabitants/NNS ./. Mr/NNP ./. Windsor/NNP Earl/NNP has/VBZ made/VBN some/DT striking/JJ observations/NNS on/IN this/DT head/NN ,/, since/IN greatly/RB extended/VBN by/IN Mr/NNP ./. Wallace's/NNP admirable/JJ researches/VBZ ,/, in/IN regard/NN to/TO the/DT great/JJ Malay/NNP Archipelago/NNP ,/, which/WDT is/VBZ traversed/VBN near/IN Celebes/NNPS by/IN a/DT space/NN of/IN deep/JJ ocean/NN ,/, and/CC this/DT separates/VBZ two/CD widely/RB distinct/JJ mammalian/JJ faunas/NNS ./. On/IN either/DT side/NN the/DT islands/NNS stand/VB on/IN a/DT moderately/RB shallow/JJ submarine/NN bank/NN ,/, and/CC these/DT islands/NNS are/VBP inhabited/VBN by/IN the/DT same/JJ or/CC by/IN closely/RB allied/VBN quadrupeds/NNS ./. I/PRP have/VBP not/RB as/IN yet/RB had/VBD time/NN to/TO follow/VB up/IN this/DT subject/NN in/IN all/DT quarters/NNS of/IN the/DT world/NN ;/: but/CC as/IN far/RB as/IN I/PRP have/VBP gone/VBN ,/, the/DT relation/NN holds/VBZ good/JJ ./. For/IN instance/NN ,/, Britain/NNP is/VBZ separated/VBN by/IN a/DT shallow/JJ channel/NN from/IN Europe/NNP ,/, and/CC the/DT mammals/NNS are/VBP the/DT same/JJ on/IN both/DT sides/NNS ;/: and/CC so/RB it/PRP is/VBZ with/IN all/DT the/DT islands/NNS near/IN the/DT shores/NNS of/IN Australia/NNP ./. The/DT West/NNP Indian/NNP Islands/NNPS ,/, on/IN the/DT other/JJ hand/NN ,/, stand/VB on/IN a/DT deeply/RB submerged/VBN bank/NN ,/, nearly/RB 1000/CD fathoms/NNS in/IN depth/NN ,/, and/CC here/RB we/PRP find/VB American/NNP forms/NNS ,/, but/CC the/DT species/NN and/CC even/RB the/DT genera/NN are/VBP quite/RB distinct/JJ ./. As/IN the/DT amount/NN of/IN modification/NN which/WDT animals/NNS of/IN all/DT kinds/NNS undergo/VB partly/RB depends/VBZ on/IN the/DT lapse/NN of/IN time/NN ,/, and/CC as/IN the/DT islands/NNS which/WDT are/VBP separated/VBN from/IN each/DT other/JJ or/CC from/IN the/DT mainland/NN by/IN shallow/JJ channels/NNS ,/, are/VBP more/JJR likely/JJ to/TO have/VB been/VBN continuously/RB united/VBN within/IN a/DT recent/JJ period/NN than/IN the/DT islands/NNS separated/VBN by/IN deeper/JJR channels/NNS ,/, we/PRP can/MD understand/VB how/WRB it/PRP is/VBZ that/IN a/DT relation/NN exists/VBZ between/IN the/DT depth/NN of/IN the/DT sea/NN separating/VBG two/CD mammalian/JJ faunas/NNS ,/, and/CC the/DT degree/NN of/IN their/PRP$ affinity/NN ,/, a/DT relation/NN which/WDT is/VBZ quite/RB inexplicable/JJ on/IN the/DT theory/NN of/IN independent/JJ acts/NNS of/IN creation/NN ./. The/DT foregoing/NN statements/NNS in/IN regard/NN to/TO the/DT inhabitants/NNS of/IN oceanic/JJ islands/NNS ,/, namely/RB ,/, the/DT fewness/NN of/IN the/DT species/NN ,/, with/IN a/DT large/JJ proportion/NN consisting/VBG of/IN endemic/JJ forms/NNS ,/, the/DT members/NNS of/IN certain/JJ groups/NNS ,/, but/CC not/RB those/DT of/IN other/JJ groups/NNS in/IN the/DT same/JJ class/NN ,/, having/VBG been/VBN modified/VBN ,/, the/DT absence/NN of/IN certain/JJ whole/JJ orders/NNS ,/, as/IN of/IN batrachians/NNS and/CC of/IN terrestrial/JJ mammals/NNS ,/, notwithstanding/IN the/DT presence/NN of/IN aerial/JJ bats/NNS ,/, the/DT singular/JJ proportions/NNS of/IN certain/JJ orders/NNS of/IN plants/NNS ,/, herbaceous/JJ forms/NNS having/VBG been/VBN developed/VBN into/IN trees/NNS ,/, &c/NN ./. ,/, seem/VB to/TO me/PRP to/TO accord/NN better/JJR with/IN the/DT belief/NN in/IN the/DT efficiency/NN of/IN occasional/JJ means/VBZ of/IN transport/NN ,/, carried/VBD on/IN during/IN a/DT long/JJ course/NN of/IN time/NN ,/, than/IN with/IN the/DT belief/NN in/IN the/DT former/JJ connection/NN of/IN all/DT oceanic/JJ islands/NNS with/IN the/DT nearest/JJS continent/NN ;/: for/IN on/IN this/DT latter/NN view/NN it/PRP is/VBZ probable/JJ that/IN the/DT various/JJ classes/NNS would/MD have/VB immigrated/VBD more/JJR uniformly/RB ,/, and/CC from/IN the/DT species/NN having/VBG entered/VBD in/IN a/DT body/NN their/PRP$ mutual/JJ relations/NNS would/MD not/RB have/VBP been/VBN much/JJ disturbed/VBN ,/, and/CC consequently/RB they/PRP would/MD either/DT have/VBP not/RB been/VBN modified/VBN ,/, or/CC all/DT the/DT species/NN in/IN a/DT more/JJR equable/JJ manner/NN ./. I/PRP do/VBP not/RB deny/VB that/IN there/EX are/VBP many/JJ and/CC serious/JJ difficulties/NNS in/IN understanding/NN how/WRB many/JJ Of/IN the/DT inhabitants/NNS of/IN the/DT inhabitants/NNS of/IN the/DT more/JJR remote/JJ islands/NNS ,/, whether/IN still/RB retaining/VBG the/DT same/JJ specific/JJ form/NN or/CC subsequently/RB modified/VBN ,/, have/VBP reached/VBN their/PRP$ present/JJ homes/NNS ./. But/CC the/DT probability/NN of/IN other/JJ islands/NNS having/VBG once/RB existed/VBD as/IN halting/VBG places/NNS ,/, of/IN which/WDT not/RB a/DT wreck/NN now/RB remains/VBZ ,/, must/MD not/RB be/VB overlooked/VBN ./. I/PRP will/MD specify/VB one/CD difficult/JJ case/NN ./. Almost/RB all/DT oceanic/JJ islands/NNS ,/, even/RB the/DT most/RBS isolated/VBN and/CC smallest/JJS ,/, are/VBP inhabited/VBN by/IN landshells/NNS ,/, generally/RB by/IN endemic/JJ species/NN ,/, but/CC sometimes/RB by/IN species/NN found/VBD elsewhere/RB ,/, striking/JJ instances/NNS of/IN which/WDT have/VBP been/VBN given/VBN by/IN Dr/NNP ./. A/DT ./. A/DT ./. Gould/NNP in/IN relation/NN to/TO the/DT Pacific/NNP ./. Now/RB it/PRP is/VBZ notorious/JJ that/IN land/NN shells/NNS are/VBP easily/RB killed/VBN by/IN sea/NN water/NN ;/: their/PRP$ eggs/NNS ,/, at/IN least/JJS such/JJ as/IN I/PRP have/VBP tried/VBD ,/, sink/VB in/IN it/PRP and/CC are/VBP killed/VBN ./. Yet/RB there/EX must/MD be/VB some/DT unknown/JJ ,/, but/CC occasionally/RB efficient/JJ means/VBZ for/IN their/PRP$ transportal/JJ ./. Would/MD the/DT just/RB hatched/VBN young/JJ sometimes/RB adhere/VB to/TO the/DT feet/NNS of/IN birds/NNS roosting/VBG on/IN the/DT ground/NN ,/, and/CC thus/RB get/VB transported/VBN ?/. It/PRP occurred/VBD to/TO me/PRP that/IN landshells/NNS ,/, when/WRB hibernating/VBG and/CC having/VBG a/DT membranous/JJ diaphragm/NN over/IN the/DT mouth/NN of/IN the/DT shell/NN ,/, might/MD be/VB floated/VBD in/IN chinks/NNS of/IN drifted/VBD timber/NN across/IN moderately/RB wide/JJ arms/NNS of/IN the/DT sea/NN ./. And/CC I/PRP find/VB that/IN several/JJ species/NN in/IN this/DT state/NN withstand/VB uninjured/JJ an/DT immersion/NN in/IN sea/NN water/NN during/IN seven/CD days/NNS :/: one/CD shell/NN ,/, the/DT Helix/NNP pomatia/NN ,/, after/IN having/VBG been/VBN thus/RB treated/VBN and/CC again/RB hibernating/VBG was/VBD put/VB into/IN sea/NN water/NN for/IN twenty/CD days/NNS ,/, and/CC perfectly/RB recovered/VBD ./. During/IN this/DT length/NN of/IN time/NN the/DT shell/NN might/MD have/VB been/VBN carried/VBD by/IN a/DT marine/NN current/JJ of/IN average/JJ swiftness/NN ,/, to/TO a/DT distance/NN of/IN 660/CD geographical/JJ miles/NNS ./. As/IN this/DT Helix/NNP has/VBZ a/DT thick/JJ calcareous/JJ operculum/NN ,/, I/PRP removed/VBN it/PRP ,/, and/CC when/WRB it/PRP had/VBD formed/VBN a/DT new/JJ membranous/JJ one/CD ,/, I/PRP again/RB immersed/VBN it/PRP for/IN fourteen/CD days/NNS in/IN sea/NN water/NN ,/, and/CC again/RB it/PRP recovered/VBD and/CC crawled/VBD away/RB ./. Baron/NNP Aucapitaine/NNP has/VBZ since/IN tried/VBD similar/JJ experiments/NNS :/: he/PRP placed/VBN 100/CD landshells/NNS ,/, belonging/VBG to/TO ten/CD species/NN ,/, in/IN a/DT box/NN pierced/VBN with/IN holes/NNS ,/, and/CC immersed/VBN it/PRP for/IN a/DT fortnight/NN in/IN the/DT sea/NN ./. Out/IN of/IN the/DT hundred/CD shells/NNS ,/, twenty/CD seven/CD recovered/VBD ./. The/DT presence/NN of/IN an/DT operculum/NN seems/VBZ to/TO have/VB been/VBN of/IN importance/NN ,/, as/IN out/IN of/IN twelve/CD specimens/NNS of/IN Cyclostoma/NNP elegans/NNS ,/, which/WDT is/VBZ thus/RB furnished/VBN ,/, eleven/CD revived/VBN ./. It/PRP is/VBZ remarkable/JJ ,/, seeing/VBG how/WRB well/RB the/DT Helix/NNP pomatia/NN resisted/VBN with/IN me/PRP the/DT salt/NN water/NN ,/, that/IN not/RB one/CD of/IN fifty/CD four/CD specimens/NNS belonging/VBG to/TO four/CD other/JJ species/NN of/IN Helix/NNP tried/VBD by/IN Aucapitaine/NNP ,/, recovered/VBD ./. It/PRP is/VBZ ,/, however/RB ,/, not/RB at/IN all/DT probable/JJ that/IN land/NN shells/NNS have/VBP often/RB been/VBN thus/RB transported/VBN ;/: the/DT feet/NNS of/IN birds/NNS offer/NN a/DT more/JJR probable/JJ method/NN ./. On/IN the/DT Relations/NNPS of/IN the/DT Inhabitants/NNS of/IN Islands/NNPS to/TO those/DT of/IN the/DT nearest/JJS Mainland/NNP The/DT most/RBS striking/JJ and/CC important/JJ fact/NN for/IN us/PRP is/VBZ the/DT affinity/NN of/IN the/DT species/NN which/WDT inhabit/VBP islands/NNS to/TO those/DT of/IN the/DT nearest/JJS mainland/NN ,/, without/IN being/VBG actually/RB the/DT same/JJ ./. Numerous/JJ instances/NNS could/MD be/VB given/VBN ./. The/DT Galapagos/NNP Archipelago/NNP ,/, situated/VBN under/IN the/DT equator/NN ,/, lies/VBZ at/IN the/DT distance/NN of/IN between/IN 500/CD and/CC 600/CD miles/NNS from/IN the/DT shores/NNS of/IN South/NNP America/NNP ./. Here/RB almost/RB every/DT product/NN of/IN the/DT land/NN and/CC of/IN the/DT water/NN bears/VBZ the/DT unmistakable/JJ stamp/NN of/IN the/DT American/NNP continent/NN ./. There/EX are/VBP twenty/CD six/CD land/NN birds/NNS ;/: of/IN these/DT ,/, twenty/CD one/CD ,/, or/CC perhaps/RB twenty/CD three/CD are/VBP ranked/VBD as/IN distinct/JJ species/NN ,/, and/CC would/MD commonly/RB be/VB assumed/VBN to/TO have/VB been/VBN here/RB created/VBN ;/: yet/RB the/DT close/VB affinity/NN of/IN most/RBS of/IN these/DT birds/NNS to/TO American/NNP species/NN is/VBZ manifest/JJ in/IN every/DT character/NN ,/, in/IN their/PRP$ habits/NNS ,/, gestures/NNS ,/, and/CC tones/NNS of/IN voice/NN ./. So/RB it/PRP is/VBZ with/IN the/DT other/JJ animals/NNS ,/, and/CC with/IN a/DT large/JJ proportion/NN of/IN the/DT plants/NNS ,/, as/IN shown/VBN by/IN Dr/NNP ./. Hooker/NNP in/IN his/PRP$ admirable/JJ Flora/NNP of/IN this/DT archipelago/NN ./. The/DT naturalist/NN ,/, looking/VBG at/IN the/DT inhabitants/NNS of/IN these/DT volcanic/JJ islands/NNS in/IN the/DT Pacific/NNP ,/, distant/JJ several/JJ hundred/CD miles/NNS from/IN the/DT continent/NN ,/, feels/VBZ that/IN he/PRP is/VBZ standing/VBG on/IN American/NNP land/NN ./. Why/WRB should/MD this/DT be/VB so/RB ?/. Why/WRB should/MD the/DT species/NN which/WDT are/VBP supposed/VBN to/TO have/VB been/VBN created/VBN in/IN the/DT Galapagos/NNP Archipelago/NNP ,/, and/CC nowhere/RB else/RB ,/, bear/VB so/RB plainly/RB the/DT stamp/NN of/IN affinity/NN to/TO those/DT created/VBN in/IN America/NNP ?/. There/EX is/VBZ nothing/NN in/IN the/DT conditions/NNS of/IN life/NN ,/, in/IN the/DT geological/JJ nature/NN of/IN the/DT islands/NNS ,/, in/IN their/PRP$ height/NN or/CC climate/NN ,/, or/CC in/IN the/DT proportions/NNS in/IN which/WDT the/DT several/JJ classes/NNS are/VBP associated/VBN together/RB ,/, which/WDT closely/RB resemble/VB ;/: the/DT conditions/NNS of/IN the/DT South/NNP American/NNP coast/NN :/: in/IN fact/NN ,/, there/EX is/VBZ a/DT considerable/JJ dissimilarity/NN in/IN all/DT these/DT respects/NNS ./. On/IN the/DT other/JJ hand/NN ,/, there/EX is/VBZ a/DT considerable/JJ degree/NN of/IN resemblance/NN in/IN the/DT volcanic/JJ nature/NN of/IN the/DT soil/NN ,/, in/IN the/DT climate/NN ,/, height/NN ,/, and/CC size/NN of/IN the/DT islands/NNS ,/, between/IN the/DT Galapagos/NNP and/CC Cape/NNP Verde/NNP Archipelagoes/NNP :/: but/CC what/WP an/DT entire/JJ and/CC absolute/JJ difference/NN in/IN their/PRP$ inhabitants!/NN The/DT inhabitants/NNS of/IN the/DT Cape/NNP Verde/NNP Islands/NNPS are/VBP related/VBN to/TO those/DT of/IN Africa/NNP ,/, like/IN those/DT of/IN the/DT Galapagos/NNP to/TO America/NNP ./. Facts/NNP such/JJ as/IN these/DT admit/VB of/IN no/DT sort/NN of/IN explanation/NN on/IN the/DT ordinary/JJ view/NN of/IN independent/JJ creation/NN ;/: whereas/IN on/IN the/DT view/NN here/RB maintained/VBN ,/, it/PRP is/VBZ obvious/JJ that/IN the/DT Galapagos/NNP Islands/NNPS would/MD be/VB likely/JJ to/TO receive/VB colonists/NNS from/IN America/NNP ,/, whether/IN by/IN occasional/JJ means/VBZ of/IN transport/NN or/CC (/( though/IN I/PRP do/VBP not/RB believe/VBP in/IN this/DT doctrine/NN )/SYM by/IN formerly/RB continuous/JJ land/NN ,/, and/CC the/DT Cape/NNP Verde/NNP Islands/NNPS from/IN Africa/NNP ;/: such/JJ colonists/NNS would/MD be/VB liable/JJ to/TO modification/NN ,/, the/DT principle/NN of/IN inheritance/NN still/RB betraying/VBG their/PRP$ original/JJ birthplace/NN ./. Many/JJ analogous/JJ facts/NNS could/MD be/VB given/VBN :/: indeed/RB it/PRP is/VBZ an/DT almost/RB universal/JJ rule/NN that/IN the/DT endemic/JJ productions/NNS of/IN islands/NNS are/VBP related/VBN to/TO those/DT of/IN the/DT nearest/JJS continent/NN ,/, or/CC of/IN the/DT nearest/JJS large/JJ island/NN ./. The/DT exceptions/NNS are/VBP few/JJ ,/, and/CC most/RBS of/IN them/PRP can/MD be/VB explained/VBD ./. Thus/RB although/IN Kerguelen/NNP Land/NNP stands/VBZ nearer/JJR to/TO Africa/NNP than/IN to/TO America/NNP ,/, the/DT plants/NNS are/VBP related/VBN ,/, and/CC that/IN very/RB closely/RB ,/, as/IN we/PRP know/VB from/IN Dr/NNP ./. Hooker's/NNP account/NN ,/, to/TO those/DT of/IN America/NNP :/: but/CC on/IN the/DT view/NN that/IN this/DT island/NN has/VBZ been/VBN mainly/RB stocked/VBN by/IN seeds/NNS brought/VBN with/IN earth/NN and/CC stones/NNS on/IN icebergs/NNS ,/, drifted/VBD by/IN the/DT prevailing/VBG currents/NNS ,/, this/DT anomaly/NN disappears/VBZ ./. New/NNP Zealand/NNP in/IN its/PRP$ endemic/JJ planes/NNS is/VBZ much/JJ more/JJR closely/RB related/VBN to/TO Australia/NNP ,/, the/DT nearest/JJS mainland/NN ,/, than/IN to/TO any/DT other/JJ region/NN :/: and/CC this/DT is/VBZ what/WP might/MD have/VB been/VBN expected/VBN ;/: but/CC it/PRP is/VBZ also/RB plainly/RB related/VBN to/TO South/NNP America/NNP ,/, which/WDT ,/, although/IN the/DT next/JJ nearest/JJS continent/NN ,/, is/VBZ so/RB enormously/RB remote/JJ ,/, that/IN the/DT fact/NN becomes/VBZ an/DT anomaly/NN ./. But/CC this/DT difficulty/NN partially/RB disappears/VBZ on/IN the/DT view/NN that/IN New/NNP Zealand/NNP ,/, South/NNP America/NNP ,/, and/CC the/DT other/JJ southern/JJ lands/NNS have/VBP been/VBN stocked/VBN in/IN part/NN from/IN a/DT nearly/RB intermediate/JJ though/IN distant/JJ point/NN ,/, namely/RB from/IN the/DT antarctic/JJ islands/NNS ,/, when/WRB they/PRP were/VBD clothed/VBN with/IN vegetation/NN ,/, during/IN a/DT warmer/JJR tertiary/JJ period/NN ,/, before/IN the/DT commencement/NN of/IN the/DT last/JJ Glacial/NNP period/NN ./. The/DT affinity/NN ,/, which/WDT though/IN feeble/JJ ,/, I/PRP am/VBP assured/VBN by/IN Dr/NNP ./. Hooker/NNP is/VBZ real/JJ ,/, between/IN the/DT flora/NNS of/IN the/DT south/RB western/JJ corner/NN of/IN Australia/NNP and/CC of/IN the/DT Cape/NNP of/IN Good/JJ Hope/NNP ,/, is/VBZ a/DT far/RB more/JJR remarkable/JJ case/NN ;/: but/CC this/DT affinity/NN is/VBZ confined/VBN to/TO the/DT plants/NNS ,/, and/CC will/MD ,/, no/DT doubt/NN ,/, some/DT day/NN be/VB explained/VBD ./. The/DT same/JJ law/NN which/WDT has/VBZ determined/VBN the/DT relationship/NN between/IN the/DT inhabitants/NNS of/IN islands/NNS and/CC the/DT nearest/JJS mainland/NN ,/, is/VBZ sometimes/RB displayed/VBN on/IN a/DT small/JJ scale/NN ,/, but/CC in/IN a/DT most/RBS interesting/JJ manner/NN ,/, within/IN the/DT limits/NNS of/IN the/DT same/JJ archipelago/NN ./. Thus/RB each/DT separate/JJ island/NN of/IN the/DT Galapagos/NNP Archipelago/NNP is/VBZ tenanted/VBN ,/, and/CC the/DT fact/NN is/VBZ a/DT marvellous/JJ one/CD ,/, by/IN many/JJ different/JJ species/NN ;/: but/CC these/DT species/NN are/VBP related/VBN to/TO each/DT other/JJ in/IN a/DT very/RB much/JJ closer/JJR manner/NN than/IN to/TO the/DT inhabitants/NNS of/IN the/DT American/NNP continent/NN ,/, or/CC of/IN any/DT other/JJ quarter/NN of/IN the/DT world/NN ./. This/DT is/VBZ what/WP might/MD have/VB been/VBN expected/VBN ,/, for/IN islands/NNS situated/VBN so/RB near/IN to/TO each/DT other/JJ would/MD almost/RB necessarily/RB receive/VB immigrants/NNS from/IN the/DT same/JJ original/JJ source/NN ,/, and/CC from/IN each/DT other/JJ ./. 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Hence/RB ,/, when/WRB in/IN former/JJ times/NNS an/DT immigrant/NN first/JJ settled/VBD on/IN one/CD of/IN the/DT islands/NNS ,/, or/CC when/WRB it/PRP subsequently/RB spread/NN from/IN one/CD to/TO another/DT ,/, it/PRP would/MD undoubtedly/RB be/VB exposed/VBN to/TO different/JJ conditions/NNS in/IN the/DT different/JJ islands/NNS ,/, for/IN it/PRP would/MD have/VB to/TO compete/VB with/IN a/DT different/JJ set/VBN of/IN organisms/NNS ;/: a/DT plant/NN ,/, for/IN instance/NN ,/, would/MD find/VB the/DT ground/NN best/JJS fitted/VBN for/IN it/PRP occupied/VBN by/IN somewhat/RB different/JJ species/NN in/IN the/DT different/JJ islands/NNS ,/, and/CC would/MD be/VB exposed/VBN to/TO the/DT attacks/NNS of/IN somewhat/RB different/JJ enemies/NNS ./. If/IN then/RB it/PRP varied/VBN ,/, natural/JJ selection/NN would/MD probably/RB favour/NN different/JJ varieties/NNS in/IN the/DT different/JJ islands/NNS ./. Some/DT species/NN ,/, however/RB ,/, might/MD spread/NN and/CC yet/RB retain/VB the/DT same/JJ character/NN throughout/IN the/DT group/NN ,/, just/RB as/IN we/PRP see/VB some/DT species/NN spreading/VBG widely/RB throughout/IN a/DT continent/NN and/CC remaining/VBG the/DT same/JJ ./. The/DT really/RB surprising/JJ fact/NN in/IN this/DT case/NN of/IN the/DT Galapagos/NNP Archipelago/NNP ,/, and/CC in/IN a/DT lesser/JJR degree/NN in/IN some/DT analogous/JJ cases/NNS ,/, is/VBZ that/IN each/DT new/JJ species/NN after/IN being/VBG formed/VBN in/IN any/DT one/CD island/NN ,/, did/VBD not/RB spread/NN quickly/RB to/TO the/DT other/JJ islands/NNS ./. 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Nevertheless/RB some/DT of/IN the/DT species/NN ,/, both/DT of/IN those/DT found/VBD in/IN other/JJ parts/NNS of/IN the/DT world/NN and/CC of/IN those/DT confined/VBN to/TO the/DT archipelago/NN ,/, are/VBP common/JJ to/TO the/DT several/JJ islands/NNS ;/: and/CC we/PRP may/MD infer/VB from/IN their/PRP$ present/JJ manner/NN of/IN distribution/NN ,/, that/IN they/PRP have/VBP spread/NN from/IN one/CD island/NN to/TO the/DT others/NNS ./. But/CC we/PRP often/RB take/VB ,/, I/PRP think/VBP ,/, an/DT erroneous/JJ view/NN of/IN the/DT probability/NN of/IN closely/RB allied/VBN species/NN invading/VBG each/DT other's/NNS territory/NN ,/, when/WRB put/VB into/IN free/JJ intercommunication/NN ./. Undoubtedly/RB ,/, if/IN one/CD species/NN has/VBZ any/DT advantage/NN over/IN another/DT ,/, it/PRP will/MD in/IN a/DT very/RB brief/JJ time/NN wholly/RB or/CC in/IN part/NN supplant/VB it/PRP ;/: but/CC if/IN both/DT are/VBP equally/RB well/RB fitted/VBN for/IN their/PRP$ own/JJ places/NNS ,/, both/DT will/MD probably/RB hold/VB their/PRP$ separate/JJ places/NNS for/IN almost/RB any/DT length/NN of/IN time/NN ./. 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CHAPTER/NNP XIV/NNP MUTUAL/JJ AFFINITIES/NNP OF/IN ORGANIC/NNP BEINGS/NNP :/: MORPHOLOGY/NNP :/: EMBRYOLOGY/NNP :/: RUDIMENTARY/NNP ORGANS/NNP Classification/NNP FROM/IN the/DT most/RBS remote/JJ period/NN in/IN the/DT history/NN of/IN the/DT world/NN organic/JJ beings/NNS have/VBP been/VBN found/VBD to/TO resemble/VB each/DT other/JJ in/IN descending/VBG degrees/NNS ,/, so/RB that/IN they/PRP can/MD be/VB classed/VBN in/IN groups/NNS under/IN groups/NNS ./. This/DT classification/NN is/VBZ not/RB arbitrary/JJ like/IN the/DT grouping/NN of/IN the/DT stars/NNS in/IN constellations/NNS ./. The/DT existence/NN of/IN groups/NNS would/MD have/VB been/VBN of/IN simpler/JJR significance/NN ,/, if/IN one/CD group/NN had/VBD been/VBN exclusively/RB fitted/VBN to/TO inhabit/VBP the/DT land/NN and/CC another/DT the/DT water/NN ;/: one/CD to/TO feed/NN on/IN flesh/NN ,/, another/DT on/IN vegetable/NN matter/NN ,/, and/CC so/RB on/IN ;/: but/CC the/DT case/NN is/VBZ widely/RB different/JJ ,/, for/IN it/PRP is/VBZ notorious/JJ how/WRB commonly/RB members/NNS of/IN even/RB the/DT same/JJ subgroup/NN have/VBP different/JJ habits/NNS ./. In/IN the/DT second/JJ and/CC fourth/JJ chapters/NNS ,/, on/IN Variation/NNP and/CC on/IN Natural/NNP Selection/NN ,/, I/PRP have/VBP attempted/VBD to/TO show/NN that/IN within/IN each/DT country/NN it/PRP is/VBZ the/DT widely/RB ranging/VBG ,/, the/DT much/JJ diffused/VBN and/CC common/JJ ,/, that/IN is/VBZ the/DT dominant/JJ species/NN ,/, belonging/VBG to/TO the/DT larger/JJR genera/NN in/IN each/DT class/NN ,/, which/WDT vary/VBP most/RBS ./. 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I/PRP request/NN the/DT reader/NN to/TO turn/VB to/TO the/DT diagram/NN illustrating/VBG the/DT action/NN ,/, as/IN formerly/RB explained/VBD ,/, of/IN these/DT several/JJ principles/NNS ;/: and/CC he/PRP will/MD see/VB that/IN the/DT inevitable/JJ result/NN is/VBZ ,/, that/IN the/DT modified/VBN descendants/NNS proceeding/NN from/IN one/CD progenitor/NN become/VB broken/VBN up/IN into/IN groups/NNS subordinate/JJ to/TO groups/NNS ./. In/IN the/DT diagram/NN each/DT letter/NN on/IN the/DT uppermost/JJS line/NN may/MD represent/VB a/DT genus/NN including/VBG several/JJ species/NN ,/, and/CC the/DT whole/JJ of/IN the/DT genera/NN along/IN this/DT upper/JJ line/NN form/NN together/RB one/CD class/NN ,/, for/IN all/DT are/VBP descended/VBD from/IN one/CD ancient/JJ parent/NN ,/, and/CC ,/, consequently/RB ,/, have/VBP inherited/VBN something/NN in/IN common/JJ ./. But/CC the/DT three/CD genera/NN on/IN the/DT left/VBN hand/NN have/VBP ,/, on/IN this/DT same/JJ principle/NN ,/, much/JJ in/IN common/JJ ,/, and/CC form/NN a/DT sub/NN family/NN ,/, distinct/JJ from/IN that/IN containing/VBG the/DT next/JJ two/CD genera/NN on/IN the/DT right/NN hand/NN ,/, which/WDT diverged/VBN from/IN a/DT common/JJ parent/NN at/IN the/DT fifth/JJ stage/NN of/IN descent/NN ./. These/DT five/CD genera/NN have/VBP also/RB much/JJ in/IN common/JJ ,/, though/IN less/JJR than/IN when/WRB grouped/VBN in/IN sub/NN families/NNS ;/: and/CC they/PRP form/NN a/DT family/NN distinct/JJ from/IN that/IN containing/VBG the/DT three/CD genera/NN still/RB farther/RB to/TO the/DT right/NN hand/NN ,/, which/WDT diverged/VBN at/IN an/DT earlier/RBR period/NN ./. And/CC all/DT these/DT genera/NN ,/, descended/VBD from/IN (/( A/DT )/SYM ,/, form/NN an/DT order/NN distinct/JJ from/IN the/DT genera/NN descended/VBD from/IN (/( I/PRP )/SYM ./. 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In/IN this/DT case/NN there/EX is/VBZ of/IN course/NN no/DT relation/NN to/TO genealogical/JJ succession/NN ,/, and/CC no/DT cause/NN can/MD at/IN present/JJ be/VB assigned/VBN for/IN their/PRP$ falling/VBG into/IN groups/NNS ./. But/CC with/IN organic/JJ beings/NNS the/DT case/NN is/VBZ different/JJ ,/, and/CC the/DT view/NN above/IN given/VBN accords/NNS with/IN their/PRP$ natural/JJ arrangement/NN in/IN group/NN under/IN group/NN ;/: and/CC no/DT other/JJ explanation/NN has/VBZ ever/RB been/VBN attempted/VBD ./. Naturalists/NNS ,/, as/IN we/PRP have/VBP seen/VBN ,/, try/VB to/TO arrange/VB the/DT species/NN ,/, genera/NN ,/, and/CC families/NNS in/IN each/DT class/NN ,/, on/IN what/WP is/VBZ called/VBN the/DT Natural/NNP System/NNP ./. But/CC what/WP is/VBZ meant/VBN by/IN this/DT system/NN ?/. 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But/CC many/JJ naturalists/NNS think/VBP that/IN something/NN more/JJR is/VBZ meant/VBN by/IN the/DT Natural/NNP System/NNP ;/: they/PRP believe/VBP that/IN it/PRP reveals/VBZ the/DT plan/NN of/IN the/DT Creator/NNP ;/: but/CC unless/IN it/PRP be/VB specified/VBN whether/IN order/NN in/IN time/NN or/CC space/NN ,/, or/CC both/DT ,/, or/CC what/WP else/RB is/VBZ meant/VBN by/IN the/DT plan/NN of/IN the/DT Creator/NNP ,/, it/PRP seems/VBZ to/TO me/PRP that/IN nothing/NN is/VBZ thus/RB added/VBD to/TO our/PRP$ knowledge/NN ./. 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No/DT one/CD regards/VBZ the/DT external/JJ similarity/NN of/IN a/DT mouse/NN to/TO a/DT shrew/NN ,/, of/IN a/DT dugong/NN to/TO a/DT whale/NN ,/, of/IN a/DT whale/NN to/TO a/DT fish/NN ,/, as/IN of/IN any/DT importance/NN ./. These/DT resemblances/NNS ,/, though/IN so/RB intimately/RB connected/VBN with/IN the/DT whole/JJ life/NN of/IN the/DT being/VBG ,/, are/VBP ranked/VBD as/IN merely/RB "/" adaptive/JJ or/CC analogical/JJ characters/NNS "/" ;/: but/CC to/TO the/DT consideration/NN of/IN these/DT resemblances/NNS we/PRP shall/MD recur/VB ./. It/PRP may/MD even/RB be/VB given/VBN as/IN a/DT general/JJ rule/NN ,/, that/IN the/DT less/JJR any/DT part/NN of/IN the/DT organisation/NN is/VBZ concerned/VBN with/IN special/JJ habits/NNS ,/, the/DT more/JJR important/JJ it/PRP becomes/VBZ for/IN classification/NN ./. As/IN an/DT instance/NN :/: Owen/NNP ,/, in/IN speaking/VBG of/IN the/DT dugong/NN ,/, says/VBZ ,/, "/" The/DT generative/JJ organs/NNS ,/, being/VBG those/DT which/WDT are/VBP most/RBS remotely/RB related/VBN to/TO the/DT habits/NNS and/CC food/NN of/IN an/DT animal/NN ,/, I/PRP have/VBP always/RB regarded/VBN as/IN affording/VBG very/RB clear/JJ indications/NNS of/IN its/PRP$ true/JJ affinities/NNS ./. We/PRP are/VBP least/JJS likely/JJ in/IN the/DT modifications/NNS of/IN these/DT organs/NNS to/TO mistake/NN a/DT merely/RB adaptive/JJ for/IN an/DT essential/JJ character/NN ./. "/" With/IN plants/NNS how/WRB remarkable/JJ it/PRP is/VBZ that/IN the/DT organs/NNS of/IN vegetation/NN ,/, on/IN which/WDT their/PRP$ nutrition/NN and/CC life/NN depend/VB ,/, are/VBP of/IN little/JJ significance/NN ;/: whereas/IN the/DT organs/NNS of/IN reproduction/NN ,/, with/IN their/PRP$ product/NN the/DT seed/NN and/CC embryo/NN ,/, are/VBP of/IN paramount/JJ importance!/NN So/RB again/RB in/IN formerly/RB discussing/VBG certain/JJ morphological/JJ characters/NNS which/WDT are/VBP not/RB functionally/RB important/JJ ,/, we/PRP have/VBP seen/VBN that/IN they/PRP are/VBP often/RB of/IN the/DT highest/JJS service/NN in/IN classification/NN ./. 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No/DT naturalist/NN can/MD have/VB worked/VBD long/JJ at/IN any/DT group/NN without/IN being/VBG struck/VBD with/IN this/DT fact/NN ;/: and/CC it/PRP has/VBZ been/VBN fully/RB acknowledged/VBD in/IN the/DT writings/NNS of/IN almost/RB every/DT author/NN ./. It/PRP will/MD suffice/VB to/TO quote/VB the/DT highest/JJS authority/NN ,/, Robert/NNP Brown/NNP ,/, who/WP ,/, in/IN speaking/VBG of/IN certain/JJ organs/NNS in/IN the/DT Proteaceae/NNP ,/, says/VBZ their/PRP$ generic/JJ importance/NN ,/, "/" like/IN that/IN of/IN all/DT their/PRP$ parts/NNS ,/, not/RB only/RB in/IN this/DT ,/, but/CC ,/, as/IN apprehend/VB ,/, in/IN every/DT natural/JJ family/NN ,/, is/VBZ very/RB unequal/JJ ,/, and/CC in/IN some/DT cases/NNS seems/VBZ to/TO be/VB entirely/RB lost/VBD ./. "/" Again/RB ,/, in/IN another/DT work/NN he/PRP says/VBZ ,/, the/DT genera/NN of/IN the/DT Connaraceae/NNP "/" differ/VBP in/IN having/VBG one/CD or/CC more/JJR ovaria/NN ,/, in/IN the/DT existence/NN or/CC absence/NN of/IN albumen/NN ,/, in/IN the/DT imbricate/VB or/CC valvular/JJ aestivation/NN ./. Any/DT one/CD of/IN these/DT characters/NNS singly/RB is/VBZ frequently/RB of/IN more/JJR than/IN generic/JJ importance/NN ,/, though/IN here/RB even/RB when/WRB all/DT taken/VBN together/RB they/PRP appear/VB insufficient/JJ to/TO separate/JJ Cnestis/NNP from/IN Connarus/NNP ./. "/" To/TO give/VB an/DT example/NN amongst/IN insects/NNS :/: in/IN one/CD great/JJ division/NN of/IN the/DT Hymenoptera/NNP ,/, the/DT antennae/NNS ,/, as/IN Westwood/NNP has/VBZ remarked/VBN ,/, are/VBP most/RBS constant/JJ in/IN structure/NN ;/: in/IN another/DT division/NN they/PRP differ/VBP much/JJ ,/, and/CC the/DT differences/NNS are/VBP of/IN quite/RB subordinate/JJ value/NN in/IN classification/NN ;/: yet/RB no/DT one/CD will/MD say/VB that/IN the/DT antennae/NNS in/IN these/DT two/CD divisions/NNS of/IN the/DT same/JJ order/NN are/VBP of/IN unequal/JJ physiological/JJ importance/NN ./. Any/DT number/NN of/IN instances/NNS could/MD be/VB given/VBN of/IN the/DT varying/VBG importance/NN for/IN classification/NN of/IN the/DT same/JJ important/JJ organ/NN within/IN the/DT same/JJ group/NN of/IN beings/NNS ./. Again/RB ,/, no/DT one/CD will/MD say/VB that/IN rudimentary/JJ or/CC atrophied/VBN organs/NNS are/VBP of/IN high/JJ physiological/JJ or/CC vital/JJ importance/NN ;/: yet/RB ,/, undoubtedly/RB ,/, organs/NNS in/IN this/DT condition/NN are/VBP often/RB of/IN much/JJ value/NN in/IN classification/NN ./. No/DT one/CD will/MD dispute/NN that/IN the/DT rudimentary/JJ teeth/NNS in/IN the/DT upper/JJ jaws/NNS of/IN young/JJ ruminants/NNS ,/, and/CC certain/JJ rudimentary/JJ bones/NNS of/IN the/DT leg/NN ,/, are/VBP highly/RB serviceable/JJ in/IN exhibiting/VBG the/DT close/VB affinity/NN between/IN ruminants/NNS and/CC pachyderms/NNS ./. Robert/NNP Brown/NNP has/VBZ strongly/RB insisted/VBD on/IN the/DT fact/NN that/IN the/DT position/NN of/IN the/DT rudimentary/JJ florets/NNS is/VBZ of/IN the/DT highest/JJS importance/NN in/IN the/DT classification/NN of/IN the/DT grasses/NNS ./. 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"/" When/WRB Aspicarpa/NNP produced/VBN in/IN France/NNP ,/, during/IN several/JJ years/NNS ,/, only/RB these/DT degraded/JJ flowers/NNS ,/, departing/VBG so/RB wonderfully/RB in/IN a/DT number/NN of/IN the/DT most/RBS important/JJ points/NNS of/IN structure/NN from/IN the/DT proper/JJ type/NN of/IN the/DT order/NN ,/, yet/RB M/NNP ./. Richard/NNP sagaciously/RB saw/VBD ,/, as/IN Jussieu/NNP observes/VBZ ,/, that/IN this/DT genus/NN should/MD still/RB be/VB retained/VBN amongst/IN the/DT Malpighiaceae/NNP ./. This/DT case/NN well/RB illustrates/VBZ the/DT spirit/NN of/IN our/PRP$ classifications/NNS ./. Practically/RB ,/, when/WRB naturalists/NNS are/VBP at/IN work/NN ,/, they/PRP do/VBP not/RB trouble/NN themselves/PRP about/IN the/DT physiological/JJ value/NN of/IN the/DT characters/NNS which/WDT they/PRP use/NN in/IN defining/VBG a/DT group/NN or/CC in/IN allocating/VBG any/DT particular/JJ species/NN ./. 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The/DT mocking/VBG forms/NNS ,/, on/IN the/DT other/JJ hand/NN ,/, that/IN inhabit/VBP the/DT same/JJ district/NN ,/, are/VBP comparatively/RB rare/JJ ,/, and/CC belong/VB to/TO rare/JJ groups/NNS ;/: hence/RB they/PRP must/MD suffer/VB habitually/RB from/IN some/DT danger/NN ,/, for/IN otherwise/RB ,/, from/IN the/DT number/NN of/IN eggs/NNS laid/VBN by/IN all/DT butterflies/NNS ,/, they/PRP would/MD in/IN three/CD or/CC four/CD generations/NNS swarm/NN over/IN the/DT whole/JJ country/NN ./. Now/RB if/IN a/DT member/NN of/IN one/CD of/IN these/DT persecuted/VBN and/CC rare/JJ groups/NNS were/VBD to/TO assume/VB a/DT dress/NN so/RB like/IN that/IN of/IN a/DT well/RB protected/VBN species/NN that/IN it/PRP continually/RB deceived/VBN the/DT practised/JJ eye/NN of/IN an/DT entomologist/NN ,/, it/PRP would/MD often/RB deceive/VB predaceous/JJ birds/NNS and/CC insects/NNS ,/, and/CC thus/RB often/RB escape/VB destruction/NN ./. Mr/NNP ./. 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Wallace/NNP and/CC Trimen/NNP have/VBP likewise/RB described/VBN several/JJ equally/RB striking/JJ cases/NNS of/IN imitation/NN in/IN the/DT Lepidoptera/NNP of/IN the/DT Malay/NNP Archipelago/NNP and/CC Africa/NNP ,/, and/CC with/IN some/DT other/JJ insects/NNS ./. Mr/NNP ./. Wallace/NNP has/VBZ also/RB detected/VBN one/CD such/JJ case/NN with/IN birds/NNS ,/, but/CC we/PRP have/VBP none/NN with/IN the/DT larger/JJR quadrupeds/NNS ./. 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In/IN drawing/VBG up/IN the/DT several/JJ series/NN he/PRP trusts/NNS chiefly/RB to/TO embryological/JJ characters/NNS ,/, but/CC receives/VBZ aid/NN from/IN homologous/RB and/CC rudimentary/JJ organs/NNS ,/, as/IN well/RB as/IN from/IN the/DT successive/JJ periods/NNS at/IN which/WDT the/DT various/JJ forms/NNS of/IN life/NN are/VBP believed/VBD to/TO have/VB first/JJ appeared/VBD in/IN our/PRP$ geological/JJ formations/NNS ./. He/PRP has/VBZ thus/RB boldly/RB made/VBN a/DT great/JJ beginning/VBG ,/, and/CC shows/VBZ us/PRP how/WRB classification/NN will/MD in/IN the/DT future/NN be/VB treated/VBN ./. Morphology/NNP We/PRP have/VBP seen/VBN that/IN the/DT members/NNS of/IN the/DT same/JJ class/NN ,/, independently/RB of/IN their/PRP$ habits/NNS of/IN life/NN ,/, resemble/VB each/DT other/JJ in/IN the/DT general/JJ plan/NN of/IN their/PRP$ organisation/NN ./. 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What/WP can/MD be/VB more/JJR curious/JJ than/IN that/IN the/DT hand/NN of/IN a/DT man/NN ,/, formed/VBN for/IN grasping/VBG ,/, that/IN of/IN a/DT mole/NN for/IN digging/VBG ,/, the/DT leg/NN of/IN the/DT horse/NN ,/, the/DT paddle/NN of/IN the/DT porpoise/NN ,/, and/CC the/DT wing/NN of/IN the/DT bat/NN ,/, should/MD all/DT be/VB constructed/VBN on/IN the/DT same/JJ pattern/NN ,/, and/CC should/MD include/VB similar/JJ bones/NNS ,/, in/IN the/DT same/JJ relative/JJ positions/NNS ?/. 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Notwithstanding/IN this/DT similarity/NN of/IN pattern/NN ,/, it/PRP is/VBZ obvious/JJ that/IN the/DT hind/JJ feet/NNS of/IN these/DT several/JJ animals/NNS are/VBP used/VBN for/IN as/IN widely/RB different/JJ purposes/NNS as/IN it/PRP is/VBZ possible/JJ to/TO conceive/VB ./. The/DT case/NN is/VBZ rendered/VBN all/DT the/DT more/JJR striking/JJ by/IN the/DT American/NNP opossums/NNS ,/, which/WDT follow/VB nearly/RB the/DT same/JJ habits/NNS of/IN life/NN as/IN some/DT of/IN their/PRP$ Australian/JJ relatives/NNS ,/, having/VBG feet/NNS constructed/VBN on/IN the/DT ordinary/JJ plan/NN ./. Professor/NNP Flower/NNP ,/, from/IN whom/WP these/DT statements/NNS are/VBP taken/VBN ,/, remarks/NNS in/IN conclusion/NN :/: "/" We/PRP may/MD call/VB this/DT conformity/NN to/TO type/NN ,/, without/IN getting/VBG much/JJ nearer/JJR to/TO an/DT explanation/NN of/IN the/DT phenomenon/NN "/" ;/: and/CC he/PRP then/RB adds/VBZ "/" but/CC is/VBZ it/PRP not/RB powerfully/RB suggestive/JJ of/IN true/JJ relationship/NN ,/, of/IN inheritance/NN from/IN a/DT common/JJ ancestor/NN ?/. "/" Geoffroy/NNP St/NNP Hilaire/NNP has/VBZ strongly/RB insisted/VBD on/IN the/DT high/JJ importance/NN of/IN relative/JJ position/NN or/CC connection/NN in/IN homologous/RB parts/NNS ;/: they/PRP may/MD differ/VB to/TO almost/RB any/DT extent/NN in/IN form/NN and/CC size/NN ,/, and/CC yet/RB remain/VB connected/VBN together/RB in/IN the/DT same/JJ invariable/JJ order/NN ./. 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The/DT same/JJ law/NN governs/VBZ the/DT construction/NN of/IN the/DT mouths/NNS and/CC limbs/NNS of/IN crustaceans/NNS ./. So/RB it/PRP is/VBZ with/IN the/DT flowers/NNS of/IN plants/NNS ./. Nothing/NN can/MD be/VB more/JJR hopeless/JJ than/IN to/TO attempt/NN to/TO explain/VB this/DT similarity/NN of/IN pattern/NN in/IN members/NNS of/IN the/DT same/JJ class/NN ,/, by/IN utility/NN or/CC by/IN the/DT doctrine/NN of/IN final/JJ causes/NNS ./. The/DT hopelessness/NN of/IN the/DT attempt/NN has/VBZ been/VBN expressly/RB admitted/VBD by/IN Owen/NNP in/IN his/PRP$ most/RBS interesting/JJ work/NN on/IN the/DT Nature/NNP of/IN Limbs/NNP ./. 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And/CC we/PRP can/MD understand/VB this/DT fact/NN ;/: for/IN in/IN molluscs/NNS ,/, even/RB in/IN the/DT lowest/JJS members/NNS of/IN the/DT class/NN ,/, we/PRP do/VBP not/RB find/VB nearly/RB so/RB much/JJ indefinite/JJ repetition/NN of/IN any/DT one/CD part/NN as/IN we/PRP find/VB in/IN the/DT other/JJ great/JJ classes/NNS of/IN the/DT animal/NN and/CC vegetable/NN kingdoms/NNS ./. But/CC morphology/NN is/VBZ a/DT much/JJ more/JJR complex/JJ subject/NN than/IN it/PRP at/IN first/JJ appears/VBZ ,/, as/IN has/VBZ lately/RB been/VBN well/RB shown/VBN in/IN a/DT remarkable/JJ paper/NN by/IN Mr/NNP ./. E/NN ./. Ray/NNP Lankester/NNP ,/, who/WP has/VBZ drawn/VBN an/DT important/JJ distinction/NN between/IN certain/JJ classes/NNS of/IN cases/NNS which/WDT have/VBP all/DT been/VBN equally/RB ranked/VBD by/IN naturalists/NNS as/IN homologous/RB ./. He/PRP proposes/VBZ to/TO call/VB the/DT structures/NNS which/WDT resemble/VB each/DT other/JJ in/IN distinct/JJ animals/NNS ,/, owing/JJ to/TO their/PRP$ descent/NN from/IN a/DT common/JJ progenitor/NN with/IN subsequent/JJ modification/NN ,/, homogenous/JJ ;/: and/CC the/DT resemblances/NNS which/WDT cannot/MD thus/RB be/VB accounted/VBD for/IN ,/, he/PRP proposes/VBZ to/TO call/VB homoplastic/JJ ./. For/IN instance/NN ,/, he/PRP believes/VBZ that/IN the/DT hearts/NNS of/IN birds/NNS and/CC mammals/NNS are/VBP as/IN a/DT whole/JJ homogenous/JJ ,/, that/IN is/VBZ ,/, have/VBP been/VBN derived/VBN from/IN a/DT common/JJ progenitor/NN ;/: but/CC that/IN the/DT four/CD cavities/NNS of/IN the/DT heart/NN in/IN the/DT two/CD classes/NNS are/VBP homoplastic/JJ ,/, that/IN is/VBZ ,/, have/VBP been/VBN independently/RB developed/VBN ./. Mr/NNP ./. 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Naturalists/NNS frequently/RB speak/VB of/IN the/DT skull/NN as/IN formed/VBN of/IN metamorphosed/VBN vertebrae/NNS ;/: the/DT jaws/NNS of/IN crabs/NNS as/IN metamorphosed/VBN legs/NNS ;/: the/DT stamens/NNS and/CC pistils/NNS in/IN flowers/NNS as/IN metamorphosed/VBN leaves/VBZ ;/: but/CC it/PRP would/MD in/IN most/RBS cases/NNS be/VB more/JJR correct/JJ ,/, as/IN Professor/NNP Huxley/NNP has/VBZ remarked/VBN ,/, to/TO speak/VB of/IN both/DT skull/NN and/CC vertebrae/NNS ,/, jaws/NNS and/CC legs/NNS ,/, &c/NN ./. ,/, as/IN having/VBG been/VBN metamorphosed/VBN ,/, not/RB one/CD from/IN the/DT other/JJ ,/, as/IN they/PRP now/RB exist/VB ,/, but/CC from/IN some/DT common/JJ and/CC simpler/JJR element/NN ./. Most/JJS naturalists/NNS ,/, however/RB ,/, use/NN such/JJ language/NN only/RB in/IN a/DT metaphorical/JJ sense/NN ;/: they/PRP are/VBP far/RB from/IN meaning/NN that/IN during/IN a/DT long/JJ course/NN of/IN descent/NN ,/, primordial/JJ organs/NNS of/IN any/DT kind/NN vertebrae/NNS in/IN the/DT one/CD case/NN and/CC legs/NNS in/IN the/DT other/JJ have/VBP actually/RB been/VBN converted/VBN into/IN skulls/NNS or/CC jaws/NNS ./. Yet/RB so/RB strong/JJ is/VBZ the/DT appearance/NN of/IN this/DT having/VBG occurred/VBD ,/, that/IN naturalists/NNS can/MD hardly/RB avoid/VB employing/VBG language/NN having/VBG this/DT plain/JJ signification/NN ./. 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A/DT certain/JJ ephemerous/JJ insect/NN (/( Chloeon/NNP )/SYM during/IN its/PRP$ development/NN ,/, moults/NNS ,/, as/IN shown/VBN by/IN Sir/NNP J/NNP ./. Lubbock/NNP ,/, above/IN twenty/CD times/NNS ,/, and/CC each/DT time/NN undergoes/VBZ a/DT certain/JJ amount/NN of/IN change/NN ;/: and/CC in/IN this/DT case/NN we/PRP see/VB the/DT act/NN of/IN metamorphosis/NN performed/VBN in/IN a/DT primary/JJ and/CC gradual/JJ manner/NN ./. Many/JJ insects/NNS ,/, and/CC especially/RB certain/JJ crustaceans/NNS ,/, show/NN us/PRP what/WP wonderful/JJ changes/NNS of/IN structure/NN can/MD be/VB effected/VBN during/IN development/NN ./. Such/JJ changes/NNS ,/, however/RB ,/, reach/VB their/PRP$ acme/NN in/IN the/DT so/RB called/VBN alternate/JJ generations/NNS of/IN some/DT of/IN the/DT lower/JJR animals/NNS ./. It/PRP is/VBZ ,/, for/IN instance/NN ,/, an/DT astonishing/JJ fact/NN that/IN a/DT delicate/JJ branching/VBG coralline/NN ,/, studded/VBN with/IN polypi/NN and/CC attached/VBN to/TO a/DT submarine/NN rock/NN ,/, should/MD produce/VB ,/, first/JJ by/IN budding/VBG and/CC then/RB by/IN transverse/JJ division/NN ,/, a/DT host/NN of/IN huge/JJ floating/VBG jelly/NN fishes/NNS ;/: and/CC that/IN these/DT should/MD produce/VB eggs/NNS ,/, from/IN which/WDT are/VBP hatched/VBN swimming/VBG animalcules/NNS ,/, which/WDT attach/VB themselves/PRP to/TO rocks/NNS and/CC become/VB developed/VBN into/IN branching/VBG corallines/NNS ;/: and/CC so/RB on/IN in/IN an/DT endless/JJ cycle/NN ./. The/DT belief/NN in/IN the/DT essential/JJ identity/NN of/IN the/DT process/NN of/IN alternate/JJ generation/NN and/CC of/IN ordinary/JJ metamorphosis/NN has/VBZ been/VBN greatly/RB strengthened/VBN by/IN Wagner's/NNP discovery/NN of/IN the/DT larva/NN or/CC maggot/NN of/IN a/DT fly/VB ,/, namely/RB the/DT Cecidomyia/NNP ,/, producing/VBG asexually/RB other/JJ larvae/NNS ,/, and/CC these/DT others/NNS ,/, which/WDT finally/RB are/VBP developed/VBN into/IN mature/JJ males/NNS and/CC females/NNS ,/, propagating/VBG their/PRP$ kind/NN in/IN the/DT ordinary/JJ manner/NN by/IN eggs/NNS ./. It/PRP may/MD be/VB worth/JJ notice/NN that/IN when/WRB Wagner's/NNP remarkable/JJ discovery/NN was/VBD first/JJ announced/VBD ,/, I/PRP was/VBD asked/VBD how/WRB was/VBD it/PRP possible/JJ to/TO account/NN for/IN the/DT larvae/NNS of/IN this/DT fly/VB having/VBG acquired/VBN the/DT power/NN of/IN asexual/JJ reproduction/NN ./. As/IN long/JJ as/IN the/DT case/NN remained/VBD unique/JJ no/DT answer/NN could/MD be/VB given/VBN ./. But/CC already/RB Grimm/NNP has/VBZ shown/VBN that/IN another/DT fly/VB ,/, a/DT Chironomus/NNP ,/, reproduces/VBZ itself/PRP in/IN nearly/RB the/DT same/JJ manner/NN ,/, and/CC he/PRP believes/VBZ that/IN this/DT occurs/VBZ frequently/RB in/IN the/DT Order/NNP ./. It/PRP is/VBZ the/DT pupa/NN ,/, and/CC not/RB the/DT larva/NN ,/, of/IN the/DT Chironomus/NNP which/WDT has/VBZ this/DT power/NN ;/: and/CC Grimm/NNP further/JJR shows/VBZ that/IN this/DT case/NN ,/, to/TO a/DT certain/JJ extent/NN ,/, "/" unites/VBZ that/IN of/IN the/DT Cecidomyia/NNP with/IN the/DT parthenogenesis/NN of/IN the/DT Coccidae/NNP "/" ;/: the/DT term/NN parthenogenesis/NN implying/VBG that/IN the/DT mature/JJ females/NNS of/IN the/DT Coccidae/NNP are/VBP capable/JJ of/IN producing/VBG fertile/JJ eggs/NNS without/IN the/DT concourse/NN of/IN the/DT males/NNS ./. Certain/JJ animals/NNS belonging/VBG to/TO several/JJ classes/NNS are/VBP now/RB known/VBN to/TO have/VB the/DT power/NN of/IN ordinary/JJ reproduction/NN at/IN an/DT unusually/RB early/JJ age/NN ;/: and/CC we/PRP have/VBP only/RB to/TO accelerate/VB parthenogenetic/JJ production/NN by/IN gradual/JJ steps/NNS to/TO an/DT earlier/RBR and/CC earlier/RBR age/NN ,/, Chironomus/NNP showing/VBG us/PRP an/DT almost/RB exactly/RB intermediate/JJ stage/NN ,/, viz/NN ./. ,/, that/IN of/IN the/DT pupa/NN and/CC we/PRP can/MD perhaps/RB account/NN for/IN the/DT marvellous/JJ case/NN of/IN the/DT Cecidomyia/NNP ./. It/PRP has/VBZ already/RB been/VBN stated/VBN that/IN various/JJ parts/NNS in/IN the/DT same/JJ individual/JJ which/WDT are/VBP exactly/RB alike/RB during/IN an/DT early/JJ embryonic/JJ period/NN ,/, become/VB widely/RB different/JJ and/CC serve/VB for/IN widely/RB different/JJ purposes/NNS in/IN the/DT adult/NN state/NN ./. So/RB again/RB it/PRP has/VBZ been/VBN shown/VBN that/IN generally/RB the/DT embryos/NNS of/IN the/DT most/RBS distinct/JJ species/NN belonging/VBG to/TO the/DT same/JJ class/NN are/VBP closely/RB similar/JJ ,/, but/CC become/VB ,/, when/WRB fully/RB developed/VBN ,/, widely/RB dissimilar/JJ ./. A/DT better/JJR proof/NN of/IN this/DT latter/NN fact/NN cannot/MD be/VB given/VBN than/IN the/DT statement/NN by/IN von/NNP Baer/NNP that/IN "/" The/DT embryos/NNS of/IN mammalia/NN ,/, of/IN birds/NNS ,/, lizards/NNS ,/, and/CC snakes/NNS ,/, probably/RB also/RB of/IN chelonia/NN are/VBP in/IN their/PRP$ earliest/JJS states/NNS exceedingly/RB like/IN one/CD another/DT ,/, both/DT as/IN a/DT whole/JJ and/CC in/IN the/DT mode/NN of/IN development/NN of/IN their/PRP$ parts/NNS ;/: so/RB much/JJ so/RB ,/, in/IN fact/NN ,/, that/IN we/PRP can/MD often/RB distinguish/VB the/DT embryos/NNS only/RB by/IN their/PRP$ size/NN ./. In/IN my/PRP$ possession/NN are/VBP two/CD little/JJ embryos/NNS in/IN spirit/NN ,/, whose/WP$ names/NNS I/PRP have/VBP omitted/VBN to/TO attach/VB ,/, and/CC at/IN present/JJ I/PRP am/VBP quite/RB unable/JJ to/TO say/VB to/TO what/WP class/NN they/PRP belong/VB ./. They/PRP may/MD be/VB lizards/NNS or/CC small/JJ birds/NNS ,/, or/CC very/RB young/JJ mammalia/NN ,/, so/RB complete/JJ is/VBZ the/DT similarity/NN in/IN the/DT mode/NN of/IN formation/NN of/IN the/DT head/NN and/CC trunk/NN in/IN these/DT animals/NNS ./. The/DT extremities/NNS ,/, however/RB ,/, are/VBP still/RB absent/JJ in/IN these/DT embryos/NNS ./. But/CC even/RB if/IN they/PRP had/VBD existed/VBD in/IN the/DT earliest/JJS stage/NN of/IN their/PRP$ development/NN we/PRP should/MD learn/VB nothing/NN ,/, for/IN the/DT feet/NNS of/IN lizards/NNS and/CC mammals/NNS ,/, the/DT wings/NNS and/CC feet/NNS of/IN birds/NNS ,/, no/DT less/JJR than/IN the/DT hands/NNS and/CC feet/NNS of/IN man/NN ,/, all/DT arise/VB from/IN the/DT same/JJ fundamental/JJ form/NN ./. "/" The/DT larvae/NNS of/IN most/RBS crustaceans/NNS ,/, at/IN corresponding/JJ stages/NNS of/IN development/NN ,/, closely/RB resemble/VB each/DT other/JJ ,/, however/RB different/JJ the/DT adult/NN may/MD become/VB ;/: and/CC so/RB it/PRP is/VBZ with/IN very/RB many/JJ other/JJ animals/NNS ./. A/DT trace/NN of/IN the/DT law/NN of/IN embryonic/JJ resemblance/NN occasionally/RB lasts/VBZ till/IN a/DT rather/RB late/JJ age/NN ;/: thus/RB birds/NNS of/IN the/DT same/JJ genus/NN ,/, and/CC of/IN allied/VBN genera/NN ,/, often/RB resemble/VB each/DT other/JJ in/IN their/PRP$ immature/JJ plumage/NN ;/: as/IN we/PRP see/VB in/IN the/DT spotted/VBD feathers/NNS in/IN the/DT young/JJ of/IN the/DT thrush/NN group/NN ./. In/IN the/DT cat/NN tribe/NN ,/, most/RBS of/IN the/DT species/NN when/WRB adult/NN are/VBP striped/JJ or/CC spotted/VBD in/IN lines/NNS ;/: and/CC stripes/NNS or/CC spots/NNS can/MD be/VB plainly/RB distinguished/VBN in/IN the/DT whelp/NN of/IN the/DT lion/NN and/CC the/DT puma/NN ./. We/PRP occasionally/RB though/IN rarely/RB see/VB something/NN of/IN the/DT same/JJ kind/NN in/IN plants/NNS ;/: thus/RB the/DT first/JJ leaves/VBZ of/IN the/DT ulex/NN or/CC furze/NN ,/, and/CC the/DT first/JJ leaves/VBZ of/IN the/DT phyllodineous/JJ aeacias/NNS ,/, are/VBP pinnate/VB or/CC divided/VBN like/IN the/DT ordinary/JJ leaves/VBZ of/IN the/DT leguminosae/NN ./. The/DT points/NNS of/IN structure/NN ,/, in/IN which/WDT the/DT embryos/NNS of/IN widely/RB different/JJ animals/NNS within/IN the/DT same/JJ class/NN resemble/VB each/DT other/JJ ,/, often/RB have/VBP no/DT direct/JJ relation/NN to/TO their/PRP$ conditions/NNS of/IN existence/NN ./. We/PRP cannot/MD ,/, for/IN instance/NN ,/, suppose/VBP that/IN in/IN the/DT embryos/NNS of/IN the/DT vertebrata/NN the/DT peculiar/JJ looplike/JJ courses/NNS of/IN the/DT arteries/NNS near/IN the/DT branchial/JJ slits/NNS are/VBP related/VBN to/TO similar/JJ conditions/NNS ,/, in/IN the/DT young/JJ mammal/NN which/WDT is/VBZ nourished/VBN in/IN the/DT womb/NN of/IN its/PRP$ mother/NN ,/, in/IN the/DT egg/NN of/IN the/DT bird/NN which/WDT is/VBZ hatched/VBN in/IN a/DT nest/NN ,/, and/CC in/IN the/DT spawn/VB of/IN a/DT frog/NN under/IN water/NN ./. We/PRP have/VBP no/DT more/JJR reason/NN to/TO believe/VB in/IN such/JJ a/DT relation/NN ,/, than/IN we/PRP have/VBP to/TO believe/VB that/IN the/DT similar/JJ bones/NNS in/IN the/DT hand/NN of/IN a/DT man/NN ,/, wing/NN of/IN a/DT bat/NN ,/, and/CC fin/NN of/IN a/DT porpoise/NN ,/, are/VBP related/VBN to/TO similar/JJ conditions/NNS of/IN life/NN ./. No/DT one/CD supposes/VBZ that/IN the/DT stripes/NNS on/IN the/DT whelp/NN of/IN a/DT lion/NN ,/, or/CC the/DT spots/NNS on/IN the/DT young/JJ blackbird/NN ,/, are/VBP of/IN any/DT use/NN to/TO these/DT animals/NNS ./. The/DT case/NN ,/, however/RB ,/, is/VBZ different/JJ when/WRB an/DT animal/NN during/IN any/DT part/NN of/IN its/PRP$ embryonic/JJ career/NN is/VBZ active/JJ ,/, and/CC has/VBZ to/TO provide/VB for/IN itself/PRP ./. The/DT period/NN of/IN activity/NN may/MD come/VB on/IN earlier/RBR or/CC later/RB in/IN life/NN ;/: but/CC whenever/WRB it/PRP comes/VBZ on/IN ,/, the/DT adaptation/NN of/IN the/DT larva/NN to/TO its/PRP$ conditions/NNS of/IN life/NN is/VBZ just/RB as/IN perfect/JJ and/CC as/IN beautiful/JJ as/IN in/IN the/DT adult/NN animal/NN ./. In/IN how/WRB important/JJ a/DT manner/NN this/DT has/VBZ acted/VBN ,/, has/VBZ recently/RB been/VBN well/RB shown/VBN by/IN Sir/NNP J/NNP ./. Lubbock/NNP in/IN his/PRP$ remarks/NNS on/IN the/DT close/VB similarity/NN of/IN the/DT larvae/NNS of/IN some/DT insects/NNS belonging/VBG to/TO very/RB different/JJ orders/NNS ,/, and/CC on/IN the/DT dissimilarity/NN of/IN the/DT larvae/NNS of/IN other/JJ insects/NNS within/IN the/DT same/JJ order/NN ,/, according/VBG to/TO their/PRP$ habits/NNS of/IN life/NN ./. Owing/RB to/TO such/JJ adaptations/NNS ,/, the/DT similarity/NN of/IN the/DT larvae/NNS of/IN allied/VBN animals/NNS is/VBZ sometimes/RB greatly/RB obscured/VBN ;/: especially/RB when/WRB there/EX is/VBZ a/DT division/NN of/IN labour/NN during/IN the/DT different/JJ stages/NNS of/IN development/NN ,/, as/IN when/WRB the/DT same/JJ larva/NN has/VBZ during/IN one/CD stage/NN to/TO search/NN for/IN food/NN ,/, and/CC during/IN another/DT stage/NN has/VBZ to/TO search/NN for/IN a/DT place/NN of/IN attachment/NN ./. Cases/NNS can/MD even/RB be/VB given/VBN of/IN the/DT larvae/NNS of/IN allied/VBN species/NN ,/, or/CC groups/NNS of/IN species/NN ,/, differing/VBG more/JJR from/IN each/DT other/JJ than/IN do/VBP the/DT adults/NNS ./. In/IN most/RBS cases/NNS ,/, however/RB ,/, the/DT larvae/NNS ,/, though/IN active/JJ ,/, still/RB obey/VB ,/, more/JJR or/CC less/JJR closely/RB ,/, the/DT law/NN of/IN common/JJ embryonic/JJ resemblance/NN ./. Cirripedes/NNP afford/VB a/DT good/JJ instance/NN of/IN this/DT ;/: even/RB the/DT illustrious/JJ Cuvier/NNP did/VBD not/RB perceive/VB that/IN a/DT barnacle/NN was/VBD a/DT crustacean/NN :/: but/CC a/DT glance/NN at/IN the/DT larva/NN shows/VBZ this/DT in/IN an/DT unmistakable/JJ manner/NN ./. 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In/IN the/DT second/JJ stage/NN ,/, answering/VBG to/TO the/DT chrysalis/NN stage/NN of/IN butterflies/NNS ,/, they/PRP have/VBP six/CD pairs/NNS of/IN beautifully/RB constructed/VBN natatory/JJ legs/NNS ,/, a/DT pair/NN of/IN magnificent/JJ compound/NN eyes/NNS ,/, and/CC extremely/RB complex/JJ antennae/NNS ;/: but/CC they/PRP have/VBP a/DT closed/VBD and/CC imperfect/JJ mouth/NN ,/, and/CC cannot/MD feed/NN :/: their/PRP$ function/NN at/IN this/DT stage/NN is/VBZ ,/, to/TO search/NN out/IN by/IN their/PRP$ well/RB developed/VBN organs/NNS of/IN sense/NN ,/, and/CC to/TO reach/VB by/IN their/PRP$ active/JJ powers/NNS of/IN swimming/VBG ,/, a/DT proper/JJ place/NN on/IN which/WDT to/TO become/VB attached/VBN and/CC to/TO undergo/VB their/PRP$ final/JJ metamorphosis/NN ./. 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If/IN ,/, on/IN the/DT other/JJ hand/NN ,/, it/PRP profited/VBD the/DT young/JJ of/IN an/DT animal/NN to/TO follow/VB habits/NNS of/IN life/NN slightly/RB different/JJ from/IN those/DT of/IN the/DT parent/NN form/NN ,/, and/CC consequently/RB to/TO be/VB constructed/VBN on/IN a/DT slightly/RB different/JJ plan/NN ,/, or/CC if/IN it/PRP profited/VBD a/DT larva/NN already/RB different/JJ from/IN its/PRP$ parent/NN to/TO change/NN still/RB further/JJR ,/, then/RB ,/, on/IN the/DT principle/NN of/IN inheritance/NN at/IN corresponding/JJ ages/NNS ,/, the/DT young/JJ or/CC the/DT larvae/NNS might/MD be/VB rendered/VBN by/IN natural/JJ selection/NN more/JJR and/CC more/JJR different/JJ from/IN their/PRP$ parents/NNS to/TO any/DT conceivable/JJ extent/NN ./. 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From/IN the/DT remarks/NNS just/RB made/VBN we/PRP can/MD see/VB how/WRB by/IN changes/NNS of/IN structure/NN in/IN the/DT young/JJ ,/, in/IN conformity/NN with/IN changed/VBN habits/NNS of/IN life/NN ,/, together/RB with/IN inheritance/NN at/IN corresponding/JJ ages/NNS ,/, animals/NNS might/MD come/VB to/TO pass/VB through/IN stages/NNS of/IN development/NN ,/, perfectly/RB distinct/JJ from/IN the/DT primordial/JJ condition/NN of/IN their/PRP$ adult/NN progenitors/NNS ./. Most/JJS of/IN our/PRP$ best/JJS authorities/NNS are/VBP now/RB convinced/VBN that/IN the/DT various/JJ larval/JJ and/CC pupal/JJ stages/NNS of/IN insects/NNS have/VBP thus/RB been/VBN acquired/VBN through/IN adaptation/NN ,/, and/CC not/RB through/IN inheritance/NN from/IN some/DT ancient/JJ form/NN ./. The/DT curious/JJ case/NN of/IN Sitaris/NNP a/DT beetle/NN which/WDT passes/VBZ through/IN certain/JJ unusual/JJ stages/NNS of/IN development/NN will/MD illustrate/VB how/WRB this/DT might/MD occur/VB ./. 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Afterwards/RB they/PRP undergo/VB a/DT complete/JJ change/NN ;/: their/PRP$ eyes/NNS disappear/VB ;/: their/PRP$ legs/NNS and/CC antennae/NNS become/VB rudimentary/JJ ,/, and/CC they/PRP feed/NN on/IN honey/NN ;/: so/RB that/IN they/PRP now/RB more/JJR closely/RB resemble/VB the/DT ordinary/JJ larvae/NNS of/IN insects/NNS ;/: ultimately/RB they/PRP undergo/VB a/DT further/JJR transformation/NN ,/, and/CC finally/RB emerge/VB as/IN the/DT perfect/JJ beetle/NN ./. 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In/IN the/DT great/JJ class/NN of/IN the/DT Crustacea/NNP ,/, forms/NNS wonderfully/RB distinct/JJ from/IN each/DT other/JJ ,/, namely/RB ,/, suctorial/JJ parasites/NNS ,/, cirripedes/NNS ,/, entomostraca/NN ,/, and/CC even/RB the/DT malacostraca/NN ,/, appear/VB at/IN first/JJ as/IN larvae/NNS under/IN the/DT nauplius/JJ form/NN ;/: and/CC as/IN these/DT larvae/NNS live/VB and/CC feed/NN in/IN the/DT open/JJ sea/NN ,/, and/CC are/VBP not/RB adapted/VBN for/IN any/DT peculiar/JJ habits/NNS of/IN life/NN ,/, and/CC from/IN other/JJ reasons/NNS assigned/VBN by/IN Fritz/NNP Muller/NNP it/PRP is/VBZ probable/JJ that/IN at/IN some/DT very/RB remote/JJ period/NN an/DT independent/JJ adult/NN animal/NN ,/, resembling/VBG the/DT nauplius/JJ ,/, existed/VBD ,/, and/CC subsequently/RB produced/VBN ,/, along/IN several/JJ divergent/JJ lines/NNS of/IN descent/NN ,/, the/DT above/IN named/VBN great/JJ crustacean/NN groups/NNS ./. 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As/IN all/DT the/DT organic/JJ beings/NNS ,/, extinct/JJ and/CC recent/JJ ,/, which/WDT have/VBP ever/RB lived/VBD ,/, can/MD be/VB arranged/VBN within/IN a/DT few/JJ great/JJ classes/NNS ;/: and/CC as/IN all/DT within/IN each/DT class/NN have/VBP ,/, according/VBG to/TO our/PRP$ theory/NN ,/, been/VBN connected/VBN together/RB by/IN fine/JJ gradations/NNS ,/, the/DT best/JJS ,/, and/CC ,/, if/IN our/PRP$ collections/NNS were/VBD nearly/RB perfect/JJ ,/, the/DT only/RB possible/JJ arrangement/NN ,/, would/MD be/VB genealogical/JJ ;/: descent/NN being/VBG the/DT hidden/VBN bond/NN of/IN connexion/NN which/WDT naturalists/NNS have/VBP been/VBN seeking/VBG under/IN the/DT term/NN of/IN the/DT Natural/NNP System/NNP ./. On/IN this/DT view/NN we/PRP can/MD understand/VB how/WRB it/PRP is/VBZ that/IN ,/, in/IN the/DT eyes/NNS of/IN most/RBS naturalists/NNS ,/, the/DT structure/NN of/IN the/DT embryo/NN is/VBZ even/RB more/JJR important/JJ for/IN classification/NN than/IN that/IN of/IN the/DT adult/NN ./. In/IN two/CD or/CC more/JJR groups/NNS of/IN animals/NNS ,/, however/RB much/JJ they/PRP may/MD differ/VB from/IN each/DT other/JJ in/IN structure/NN and/CC habits/NNS in/IN their/PRP$ adult/NN condition/NN ,/, if/IN they/PRP pass/VB through/IN closely/RB similar/JJ embryonic/JJ stages/NNS ,/, we/PRP may/MD feel/VB assured/VBN that/IN they/PRP all/DT are/VBP descended/VBD from/IN one/CD parent/NN form/NN ,/, and/CC are/VBP therefore/RB closely/RB related/VBN ./. Thus/RB ,/, community/NN in/IN embryonic/JJ structure/NN reveals/VBZ community/NN of/IN descent/NN ;/: but/CC dissimilarity/NN in/IN embryonic/JJ development/NN does/VBZ not/RB prove/VB discommunity/NN of/IN descent/NN ,/, for/IN in/IN one/CD of/IN two/CD groups/NNS the/DT developmental/JJ stages/NNS may/MD have/VB been/VBN suppressed/VBN ,/, or/CC may/MD have/VB been/VBN so/RB greatly/RB modified/VBN through/IN adaptation/NN to/TO new/JJ habits/NNS of/IN life/NN ,/, as/IN to/TO be/VB no/DT longer/RB recognisable/JJ ./. Even/RB in/IN groups/NNS ,/, in/IN which/WDT the/DT adults/NNS have/VBP been/VBN modified/VBN to/TO an/DT extreme/JJ degree/NN ,/, community/NN of/IN origin/NN is/VBZ often/RB revealed/VBD by/IN the/DT structure/NN of/IN the/DT larvae/NNS ;/: we/PRP have/VBP seen/VBN ,/, for/IN instance/NN ,/, that/IN cirripedes/NNS ,/, though/IN externally/RB so/RB like/IN shell/NN fish/NN ,/, are/VBP at/IN once/RB known/VBN by/IN their/PRP$ larvae/NNS to/TO belong/VB to/TO the/DT great/JJ class/NN of/IN crustaceans/NNS ./. As/IN the/DT embryo/NN often/RB shows/VBZ us/PRP more/JJR or/CC less/JJR plainly/RB the/DT structure/NN of/IN the/DT less/JJR modified/VBN and/CC ancient/JJ progenitor/NN of/IN the/DT group/NN ,/, we/PRP can/MD see/VB why/WRB ancient/JJ and/CC extinct/JJ forms/NNS so/RB resemble/VB in/IN their/PRP$ adult/NN state/NN the/DT embryos/NNS of/IN existing/VBG species/NN of/IN the/DT same/JJ class/NN ./. 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It/PRP should/MD also/RB be/VB borne/VBN in/IN mind/NN ,/, that/IN the/DT law/NN may/MD be/VB true/JJ ,/, but/CC yet/RB ,/, owing/JJ to/TO the/DT geological/JJ record/NN not/RB extending/VBG far/RB enough/RB back/RB in/IN time/NN ,/, may/MD remain/VB for/IN a/DT long/JJ period/NN ,/, or/CC for/IN ever/RB ,/, incapable/JJ of/IN demonstration/NN ./. The/DT law/NN will/MD not/RB strictly/RB hold/VB good/JJ in/IN those/DT cases/NNS in/IN which/WDT an/DT ancient/JJ form/NN became/VBD adapted/VBN in/IN its/PRP$ larvae/NNS state/NN to/TO some/DT special/JJ line/NN of/IN life/NN ,/, and/CC transmitted/VBN the/DT same/JJ larval/JJ state/NN to/TO a/DT whole/JJ group/NN of/IN descendants/NNS ;/: for/IN such/JJ larvae/NNS will/MD not/RB resemble/VB any/DT still/RB more/JJR ancient/JJ form/NN in/IN its/PRP$ adult/NN state/NN ./. Thus/RB ,/, as/IN it/PRP seems/VBZ to/TO me/PRP ,/, the/DT leading/VBG facts/NNS in/IN embryology/NN ,/, which/WDT are/VBP second/JJ to/TO none/NN in/IN importance/NN ,/, are/VBP explained/VBD on/IN the/DT principle/NN of/IN variations/NNS in/IN the/DT many/JJ descendants/NNS from/IN some/DT one/CD ancient/JJ progenitor/NN ,/, having/VBG appeared/VBD at/IN a/DT not/RB very/RB early/JJ period/NN of/IN life/NN ,/, and/CC having/VBG been/VBN inherited/VBN at/IN a/DT corresponding/JJ period/NN ./. Embryology/NNP rises/VBZ greatly/RB in/IN interest/NN ,/, when/WRB we/PRP look/VB at/IN the/DT embryo/NN as/IN a/DT picture/NN ,/, more/JJR or/CC less/JJR obscured/VBN ,/, of/IN the/DT progenitor/NN ,/, either/DT in/IN its/PRP$ adult/NN or/CC larval/JJ state/NN ,/, of/IN all/DT the/DT members/NNS of/IN the/DT same/JJ great/JJ class/NN ./. Rudimentary/NNP ,/, Atrophied/VBN ,/, and/CC Aborted/JJ Organs/NNPS Organs/NNPS or/CC parts/NNS in/IN this/DT strange/JJ condition/NN ,/, bearing/VBG the/DT plain/JJ stamp/NN of/IN inutility/NN ,/, are/VBP extremely/RB common/JJ ,/, or/CC even/RB general/JJ ,/, throughout/IN nature/NN ./. It/PRP would/MD be/VB impossible/JJ to/TO name/NN one/CD of/IN the/DT higher/JJR animals/NNS in/IN which/WDT some/DT part/NN or/CC other/JJ is/VBZ not/RB in/IN a/DT rudimentary/JJ condition/NN ./. In/IN the/DT mammalia/NN ,/, for/IN instance/NN ,/, the/DT males/NNS possess/VBP rudimentary/JJ mammae/NN ;/: in/IN snakes/NNS one/CD lobe/NN of/IN the/DT lungs/NNS is/VBZ rudimentary/JJ ;/: in/IN birds/NNS the/DT "/" bastardwing/VBG "/" may/MD safely/RB be/VB considered/VBN as/IN a/DT rudimentary/JJ digit/NN ,/, and/CC in/IN some/DT species/NN the/DT whole/JJ wing/NN is/VBZ so/RB far/RB rudimentary/JJ that/IN it/PRP cannot/MD be/VB used/VBN for/IN flight/NN ./. What/WP can/MD be/VB more/JJR curious/JJ than/IN the/DT presence/NN of/IN teeth/NNS in/IN foetal/JJ whales/NNS ,/, which/WDT when/WRB grown/VBN up/IN have/VBP not/RB a/DT tooth/NN in/IN their/PRP$ heads/NNS ;/: or/CC the/DT teeth/NNS ,/, which/WDT never/RB cut/VB through/IN the/DT gums/NNS ,/, in/IN the/DT upper/JJ jaws/NNS of/IN unborn/JJ calves/NNS ?/. Rudimentary/NNP organs/NNS plainly/RB declare/VB their/PRP$ origin/NN and/CC meaning/NN in/IN various/JJ ways/NNS ./. There/EX are/VBP beetles/NNS belonging/VBG to/TO closely/RB allied/VBN species/NN ,/, or/CC even/RB to/TO the/DT same/JJ identical/JJ species/NN ,/, which/WDT have/VBP either/DT full/JJ sized/VBD and/CC perfect/JJ wings/NNS ,/, or/CC mere/JJ rudiments/NNS of/IN membrane/NN ,/, which/WDT not/RB rarely/RB lie/VB under/IN wing/NN covers/VBZ firmly/RB soldered/VBN together/RB ;/: and/CC in/IN these/DT cases/NNS it/PRP is/VBZ impossible/JJ to/TO doubt/NN ,/, that/IN the/DT rudiments/NNS represent/VB wings/NNS ./. Rudimentary/NNP organs/NNS sometimes/RB retain/VB their/PRP$ potentiality/NN :/: this/DT occasionally/RB occurs/VBZ with/IN the/DT mammae/NN of/IN male/JJ mammals/NNS ,/, which/WDT have/VBP been/VBN known/VBN to/TO become/VB well/RB developed/VBN and/CC to/TO secrete/NN milk/NN ./. So/RB again/RB in/IN the/DT udders/NNS in/IN the/DT genus/NN Bos/NNP ,/, there/EX are/VBP normally/RB four/CD developed/VBN and/CC two/CD rudimentary/JJ teats/NNS ;/: but/CC the/DT latter/NN in/IN our/PRP$ domestic/JJ cows/NNS sometimes/RB become/VB well/RB developed/VBN and/CC yield/VB milk/NN ./. In/IN regard/NN to/TO plants/NNS the/DT petals/NNS are/VBP sometimes/RB rudimentary/JJ ,/, and/CC sometimes/RB well/RB developed/VBN in/IN the/DT individuals/NNS of/IN the/DT same/JJ species/NN ./. In/IN certain/JJ plants/NNS having/VBG separated/VBN sexes/NNS Kolreuter/NNP found/VBD that/IN by/IN crossing/VBG a/DT species/NN ,/, in/IN which/WDT the/DT male/JJ flowers/NNS included/VBD a/DT rudiment/NN of/IN a/DT pistil/NN ,/, with/IN an/DT hermaphrodite/NN species/NN ,/, having/VBG of/IN course/NN a/DT well/RB developed/VBN pistil/NN ,/, the/DT rudiment/NN in/IN the/DT hybrid/JJ offspring/NN was/VBD much/JJ increased/VBN in/IN size/NN ;/: and/CC this/DT clearly/RB shows/VBZ that/IN the/DT rudimentary/JJ and/CC perfect/JJ pistils/NNS are/VBP essentially/RB alike/RB in/IN nature/NN ./. An/DT animal/NN may/MD possess/VB various/JJ parts/NNS in/IN a/DT perfect/JJ state/NN ,/, and/CC yet/RB they/PRP may/MD in/IN one/CD sense/NN be/VB rudimentary/JJ ,/, for/IN they/PRP are/VBP useless/JJ :/: thus/RB the/DT tadpole/NN of/IN the/DT common/JJ salamander/NN or/CC water/NN newt/NN ,/, as/IN Mr/NNP ./. G/NN ./. H/NNP ./. Lewes/NNP remarks/NNS ,/, "/" has/VBZ gills/NNS ,/, and/CC passes/VBZ its/PRP$ existence/NN in/IN the/DT water/NN ;/: but/CC the/DT Salamandra/NNP atra/NN ,/, which/WDT lives/NNS high/JJ up/IN among/IN the/DT mountains/NNS ,/, brings/VBZ forth/RB its/PRP$ young/JJ full/JJ formed/VBN ./. This/DT animal/NN never/RB lives/NNS in/IN the/DT water/NN ./. Yet/RB if/IN we/PRP open/JJ a/DT gravid/JJ female/JJ ,/, we/PRP find/VB tadpoles/NNS inside/IN her/PRP$ with/IN exquisitely/RB feathered/JJ gills/NNS ;/: and/CC when/WRB placed/VBN in/IN water/NN they/PRP swim/VB about/IN like/IN the/DT tadpoles/NNS of/IN the/DT water/NN newt/NN ./. Obviously/RB this/DT aquatic/JJ organisation/NN has/VBZ no/DT reference/NN to/TO the/DT future/NN life/NN of/IN the/DT animal/NN ,/, nor/CC has/VBZ it/PRP any/DT adaptation/NN to/TO its/PRP$ embryonic/JJ condition/NN ;/: it/PRP has/VBZ solely/RB reference/NN to/TO ancestral/JJ adaptations/NNS ,/, it/PRP repeats/VBZ a/DT phase/NN in/IN the/DT development/NN of/IN its/PRP$ progenitors/NNS ./. "/" An/DT organ/NN ,/, serving/VBG for/IN two/CD purposes/NNS ,/, may/MD become/VB rudimentary/JJ or/CC utterly/RB aborted/JJ for/IN one/CD ,/, even/RB the/DT more/JJR important/JJ purpose/NN ,/, and/CC remain/VB perfectly/RB efficient/JJ for/IN the/DT other/JJ ./. Thus/RB in/IN plants/NNS ,/, the/DT office/NN of/IN the/DT pistil/NN is/VBZ to/TO allow/VB the/DT pollen/NN tubes/NNS to/TO reach/VB the/DT ovules/NNS within/IN the/DT ovarium/NN ./. The/DT pistil/NN consists/VBZ of/IN a/DT stigma/NN supported/VBN on/IN a/DT style/NN ;/: but/CC in/IN some/DT Compositae/NNP ,/, the/DT male/JJ florets/NNS ,/, which/WDT of/IN course/NN cannot/MD be/VB fecundated/VBN ,/, have/VBP a/DT rudimentary/JJ pistil/NN ,/, for/IN it/PRP is/VBZ not/RB crowned/VBN with/IN a/DT stigma/NN ;/: but/CC the/DT style/NN remains/VBZ well/RB developed/VBN and/CC is/VBZ clothed/VBN in/IN the/DT usual/JJ manner/NN with/IN hairs/NNS ,/, which/WDT serve/VB to/TO brush/NN the/DT pollen/NN out/IN of/IN the/DT surrounding/VBG and/CC conjoined/VBN anthers/NNS ./. Again/RB ,/, an/DT organ/NN may/MD become/VB rudimentary/JJ for/IN its/PRP$ proper/JJ purpose/NN ,/, and/CC be/VB used/VBN for/IN a/DT distinct/JJ one/CD :/: in/IN certain/JJ fishes/NNS the/DT swimbladder/NN seems/VBZ to/TO be/VB rudimentary/JJ for/IN its/PRP$ proper/JJ function/NN of/IN giving/VBG buoyancy/NN ,/, but/CC has/VBZ become/VB converted/VBN into/IN a/DT nascent/JJ breathing/NN organ/NN or/CC lung/NN ./. Many/JJ similar/JJ instances/NNS could/MD be/VB given/VBN ./. Useful/JJ organs/NNS ,/, however/RB little/JJ they/PRP may/MD be/VB developed/VBN ,/, unless/IN we/PRP have/VBP reason/NN to/TO suppose/VB that/IN they/PRP were/VBD formerly/RB more/JJR highly/RB developed/VBN ,/, ought/MD not/RB to/TO be/VB considered/VBN as/IN rudimentary/JJ ./. They/PRP may/MD be/VB in/IN a/DT nascent/JJ condition/NN ,/, and/CC in/IN progress/NN towards/IN further/JJR development/NN ./. Rudimentary/NNP organs/NNS ,/, on/IN the/DT other/JJ hand/NN ,/, are/VBP either/DT quite/RB useless/JJ ,/, such/JJ as/IN teeth/NNS which/WDT never/RB cut/VB through/IN the/DT gums/NNS ,/, or/CC almost/RB useless/JJ ,/, such/JJ as/IN the/DT wings/NNS of/IN an/DT ostrich/JJ ,/, which/WDT serve/VB merely/RB as/IN sails/NNS ./. As/IN organs/NNS in/IN this/DT condition/NN would/MD formerly/RB ,/, when/WRB still/RB less/JJR developed/VBN ,/, have/VBP been/VBN of/IN even/RB less/JJR use/NN than/IN at/IN present/JJ ,/, they/PRP cannot/MD formerly/RB have/VBP been/VBN produced/VBN through/IN variation/NN and/CC natural/JJ selection/NN ,/, which/WDT acts/NNS solely/RB by/IN the/DT preservation/NN of/IN useful/JJ modifications/NNS ./. They/PRP have/VBP been/VBN partially/RB retained/VBN by/IN the/DT power/NN of/IN inheritance/NN ,/, and/CC relate/VBP to/TO a/DT former/JJ state/NN of/IN things/NNS ./. It/PRP is/VBZ ,/, however/RB ,/, often/RB difficult/JJ to/TO distinguish/VB between/IN rudimentary/JJ and/CC nascent/JJ organs/NNS ;/: for/IN we/PRP can/MD judge/NN only/RB by/IN analogy/NN whether/IN a/DT part/NN is/VBZ capable/JJ of/IN further/JJR development/NN ,/, in/IN which/WDT case/NN alone/RB it/PRP deserves/VBZ to/TO be/VB called/VBN nascent/JJ ./. Organs/NNPS in/IN this/DT condition/NN will/MD always/RB be/VB somewhat/RB rare/JJ ;/: for/IN beings/NNS thus/RB provided/VBN will/MD commonly/RB have/VBP been/VBN supplanted/VBN by/IN their/PRP$ successors/NNS with/IN the/DT same/JJ organ/NN in/IN a/DT more/JJR perfect/JJ state/NN ,/, and/CC consequently/RB will/MD have/VB become/VB long/JJ ago/RB extinct/JJ ./. The/DT wing/NN of/IN the/DT penguin/NN is/VBZ of/IN high/JJ service/NN ,/, acting/VBG as/IN a/DT fin/NN ;/: it/PRP may/MD ,/, therefore/RB ,/, represent/VB the/DT nascent/JJ state/NN of/IN the/DT wing/NN :/: not/RB that/IN I/PRP believe/VBP this/DT to/TO be/VB the/DT case/NN ;/: it/PRP is/VBZ more/JJR probably/RB a/DT reduced/VBN organ/NN ,/, modified/VBN for/IN a/DT new/JJ function/NN :/: the/DT wing/NN of/IN the/DT Apteryx/NNP ,/, on/IN the/DT other/JJ hand/NN ,/, is/VBZ quite/RB useless/JJ ,/, and/CC is/VBZ truly/RB rudimentary/JJ ./. Owen/NNP considers/VBZ the/DT simple/JJ filamentary/JJ limbs/NNS of/IN the/DT lepidosiren/NN as/IN the/DT "/" beginnings/NNS of/IN organs/NNS which/WDT attain/VB full/JJ functional/JJ development/NN in/IN higher/JJR vertebrates/NNS "/" ;/: but/CC ,/, according/VBG to/TO the/DT view/NN lately/RB advocated/VBN by/IN Dr/NNP ./. Gunther/NNP ,/, they/PRP are/VBP probably/RB remnants/NNS ,/, consisting/VBG of/IN the/DT persistent/JJ axis/NN of/IN a/DT fin/NN ,/, with/IN the/DT lateral/JJ rays/NNS of/IN branches/NNS aborted/JJ ./. The/DT mammary/JJ glands/NNS of/IN the/DT Ornithorhynchus/NNP may/MD be/VB considered/VBN ,/, in/IN comparison/NN with/IN the/DT udders/NNS of/IN a/DT cow/NN ,/, as/IN in/IN a/DT nascent/JJ condition/NN ./. The/DT ovigerous/JJ frena/NN of/IN certain/JJ cirripedes/NNS ,/, which/WDT have/VBP ceased/VBD to/TO give/VB attachment/NN to/TO the/DT ova/NN and/CC are/VBP feebly/RB developed/VBN ,/, are/VBP nascent/JJ branchiae/NN ./. Rudimentary/NNP organs/NNS in/IN the/DT individuals/NNS of/IN the/DT same/JJ species/NN are/VBP very/RB liable/JJ to/TO vary/VB in/IN the/DT degree/NN of/IN their/PRP$ development/NN and/CC in/IN other/JJ respects/NNS ./. In/IN closely/RB allied/VBN species/NN ,/, also/RB ,/, the/DT extent/NN to/TO which/WDT the/DT same/JJ organ/NN has/VBZ been/VBN reduced/VBN occasionally/RB differs/VBZ much/JJ ./. This/DT latter/NN fact/NN is/VBZ well/RB exemplified/VBN in/IN the/DT state/NN of/IN the/DT wings/NNS of/IN female/JJ moths/NNS belonging/VBG to/TO the/DT same/JJ family/NN ./. Rudimentary/NNP organs/NNS may/MD be/VB utterly/RB aborted/JJ ;/: and/CC this/DT implies/VBZ ,/, that/IN in/IN certain/JJ animals/NNS or/CC plants/NNS ,/, parts/NNS are/VBP entirely/RB absent/JJ which/WDT analogy/NN would/MD lead/VB us/PRP to/TO expect/VB to/TO find/VB in/IN them/PRP ,/, and/CC which/WDT are/VBP occasionally/RB found/VBD in/IN monstrous/JJ individuals/NNS ./. Thus/RB in/IN most/RBS of/IN the/DT Scrophulariaceae/NNP the/DT fifth/JJ stamen/NN is/VBZ utterly/RB aborted/JJ ;/: yet/RB we/PRP may/MD conclude/VB that/IN a/DT fifth/JJ stamen/NN once/RB existed/VBD ,/, for/IN a/DT rudiment/NN of/IN it/PRP is/VBZ found/VBN in/IN many/JJ species/NN of/IN the/DT family/NN ,/, and/CC this/DT rudiment/NN occasionally/RB becomes/VBZ perfectly/RB developed/VBN ,/, as/IN may/MD sometimes/RB be/VB seen/VBN in/IN the/DT common/JJ snap/VB dragon/NN ./. In/IN tracing/VBG the/DT homologies/NNS of/IN any/DT part/NN in/IN different/JJ members/NNS of/IN the/DT same/JJ class/NN ,/, nothing/NN is/VBZ more/JJR common/JJ ,/, or/CC ,/, in/IN order/NN fully/RB to/TO understand/VB the/DT relations/NNS of/IN the/DT parts/NNS ,/, more/JJR useful/JJ than/IN the/DT discovery/NN of/IN rudiments/NNS ./. This/DT is/VBZ well/RB shown/VBN in/IN the/DT drawings/NNS given/VBN by/IN Owen/NNP of/IN the/DT leg/NN bones/NNS of/IN the/DT horse/NN ,/, ox/NN ,/, and/CC rhinoceros/NN ./. It/PRP is/VBZ an/DT important/JJ fact/NN that/IN rudimentary/JJ organs/NNS ,/, such/JJ as/IN teeth/NNS in/IN the/DT upper/JJ jaws/NNS of/IN whales/NNS and/CC ruminants/NNS ,/, can/MD often/RB be/VB detected/VBN in/IN the/DT embryo/NN ,/, but/CC afterwards/RB wholly/RB disappear/VB ./. It/PRP is/VBZ also/RB ,/, I/PRP believe/VBP ,/, a/DT universal/JJ rule/NN ,/, that/IN a/DT rudimentary/JJ part/NN is/VBZ of/IN greater/JJR size/NN in/IN the/DT embryo/NN relatively/RB to/TO the/DT adjoining/VBG parts/NNS ,/, than/IN in/IN the/DT adult/NN ;/: so/RB that/IN the/DT organ/NN at/IN this/DT early/JJ age/NN is/VBZ less/JJR rudimentary/JJ ,/, or/CC even/RB cannot/MD be/VB said/VBD to/TO be/VB in/IN any/DT degree/NN rudimentary/JJ ./. Hence/RB rudimentary/JJ organs/NNS in/IN the/DT adult/NN are/VBP often/RB said/VBD to/TO have/VB retained/VBN their/PRP$ embryonic/JJ condition/NN ./. I/PRP have/VBP now/RB given/VBN the/DT leading/VBG facts/NNS with/IN respect/NN to/TO rudimentary/JJ organs/NNS ./. In/IN reflecting/VBG on/IN them/PRP ,/, every/DT one/CD must/MD be/VB struck/VBD with/IN astonishment/NN ;/: for/IN the/DT same/JJ reasoning/NN power/NN which/WDT tells/VBZ us/PRP that/IN most/RBS parts/NNS and/CC organs/NNS are/VBP exquisitely/RB adapted/VBN for/IN certain/JJ purposes/NNS ,/, tells/VBZ us/PRP with/IN equal/JJ plainness/NN that/IN these/DT rudimentary/JJ or/CC atrophied/VBN organs/NNS are/VBP imperfect/JJ and/CC useless/JJ ./. In/IN works/NNS on/IN natural/JJ history/NN ,/, rudimentary/JJ organs/NNS are/VBP generally/RB said/VBD to/TO have/VB been/VBN created/VBN "/" for/IN the/DT sake/NN of/IN symmetry/NN ,/, "/" or/CC in/IN order/NN "/" to/TO complete/JJ the/DT scheme/NN of/IN nature/NN ./. "/" But/CC this/DT is/VBZ not/RB an/DT explanation/NN ,/, merely/RB a/DT re/NN statement/NN of/IN the/DT fact/NN ./. Nor/CC is/VBZ it/PRP consistent/JJ with/IN itself/PRP ;/: thus/RB the/DT boa/NN constrictor/NN has/VBZ rudiments/NNS of/IN hind/JJ limbs/NNS and/CC of/IN a/DT pelvis/NN ,/, and/CC if/IN it/PRP be/VB said/VBD that/IN these/DT bones/NNS have/VBP been/VBN retained/VBN "/" to/TO complete/JJ the/DT scheme/NN of/IN nature/NN ,/, "/" why/WRB ,/, as/IN Professor/NNP Weismann/NNP asks/VBZ ,/, have/VBP they/PRP not/RB been/VBN retained/VBN by/IN other/JJ snakes/NNS ,/, which/WDT do/VBP not/RB possess/VBP even/RB a/DT vestige/NN of/IN these/DT same/JJ bones/NNS ?/. What/WP would/MD be/VB thought/VBD of/IN an/DT astronomer/NN who/WP maintained/VBN that/IN the/DT satellites/NNS revolve/VB in/IN elliptic/JJ courses/NNS round/NN their/PRP$ planets/NNS "/" for/IN the/DT sake/NN of/IN symmetry/NN ,/, "/" because/IN the/DT planets/NNS thus/RB revolve/VB round/NN the/DT sun/NN ?/. An/DT eminent/JJ physiologist/NN accounts/NNS for/IN the/DT presence/NN of/IN rudimentary/JJ organs/NNS ,/, by/IN supposing/VBG that/IN they/PRP serve/VB to/TO excrete/VB matter/NN in/IN excess/JJ ,/, or/CC matter/NN injurious/JJ to/TO the/DT system/NN ;/: but/CC can/MD we/PRP suppose/VBP that/IN the/DT minute/NN papilla/NN ,/, which/WDT often/RB represents/VBZ the/DT pistil/NN in/IN male/JJ flowers/NNS ,/, and/CC which/WDT is/VBZ formed/VBN of/IN mere/JJ cellular/JJ tissue/NN ,/, can/MD thus/RB act/NN ?/. Can/MD we/PRP suppose/VBP that/IN rudimentary/JJ teeth/NNS ,/, which/WDT are/VBP subsequently/RB absorbed/VBN ,/, are/VBP beneficial/JJ to/TO the/DT rapidly/RB growing/VBG embryonic/JJ calf/NN by/IN removing/VBG matter/NN so/RB precious/JJ as/IN phosphate/NN of/IN lime/NN ?/. When/WRB a/DT man's/NNS fingers/NNS have/VBP been/VBN amputated/VBN ,/, imperfect/JJ nails/NNS have/VBP been/VBN known/VBN to/TO appear/VB on/IN the/DT stumps/NNS ,/, and/CC I/PRP could/MD as/IN soon/RB believe/VBP that/IN these/DT vestiges/NNS of/IN nails/NNS are/VBP developed/VBN in/IN order/NN to/TO excrete/VB horny/JJ matter/NN ,/, as/IN that/IN the/DT rudimentary/JJ nails/NNS on/IN the/DT fin/NN of/IN the/DT manatee/NN have/VBP been/VBN developed/VBN for/IN this/DT same/JJ purpose/NN ./. On/IN the/DT view/NN of/IN descent/NN with/IN modification/NN ,/, the/DT origin/NN of/IN rudimentary/JJ organs/NNS is/VBZ comparatively/RB simple/JJ ;/: and/CC we/PRP can/MD understand/VB to/TO a/DT large/JJ extent/NN the/DT laws/NNS governing/VBG their/PRP$ imperfect/JJ development/NN ./. We/PRP have/VBP plenty/NN of/IN cases/NNS of/IN rudimentary/JJ organs/NNS in/IN our/PRP$ domestic/JJ productions/NNS ,/, as/IN the/DT stump/NN of/IN a/DT tail/NN in/IN tailless/JJ breeds/NNS ,/, the/DT vestige/NN of/IN an/DT ear/NN in/IN earless/JJ breeds/NNS of/IN sheep/NN ,/, the/DT reappearance/NN of/IN minute/NN dangling/VBG horns/NNS in/IN hornless/JJ breeds/NNS of/IN cattle/NNS ,/, more/JJR especially/RB ,/, according/VBG to/TO Youatt/NNP ,/, in/IN young/JJ animals/NNS ,/, and/CC the/DT state/NN of/IN the/DT whole/JJ flower/NN in/IN the/DT cauliflower/NN ./. We/PRP often/RB see/VB rudiments/NNS of/IN various/JJ parts/NNS in/IN monsters/NNS ;/: but/CC I/PRP doubt/NN whether/IN any/DT of/IN these/DT cases/NNS throw/VB light/NN on/IN the/DT origin/NN of/IN rudimentary/JJ organs/NNS in/IN a/DT state/NN of/IN nature/NN ,/, further/JJR than/IN by/IN showing/VBG that/IN rudiments/NNS can/MD be/VB produced/VBN ;/: for/IN the/DT balance/NN of/IN evidence/NN clearly/RB indicates/VBZ that/IN species/NN under/IN nature/NN do/VBP not/RB undergo/VB great/JJ and/CC abrupt/JJ changes/NNS ./. But/CC we/PRP learn/VB from/IN the/DT study/NN of/IN our/PRP$ domestic/JJ productions/NNS that/IN the/DT disuse/NN of/IN parts/NNS leads/VBZ to/TO their/PRP$ reduced/VBN size/NN ;/: and/CC that/IN the/DT result/NN is/VBZ inherited/VBN ./. It/PRP appears/VBZ probable/JJ that/IN disuse/NN has/VBZ been/VBN the/DT main/JJ agent/NN in/IN rendering/VBG organs/NNS rudimentary/JJ ./. It/PRP would/MD at/IN first/JJ lead/VB by/IN slow/JJ steps/NNS to/TO the/DT more/JJR and/CC more/JJR complete/JJ reduction/NN of/IN a/DT part/NN ,/, until/IN at/IN last/JJ it/PRP became/VBD rudimentary/JJ ,/, as/IN in/IN the/DT case/NN of/IN the/DT eyes/NNS of/IN animals/NNS inhabiting/VBG dark/JJ caverns/NNS ,/, and/CC of/IN the/DT wings/NNS of/IN birds/NNS inhabiting/VBG oceanic/JJ islands/NNS ,/, which/WDT have/VBP seldom/RB been/VBN forced/VBN by/IN beasts/NNS of/IN prey/NN to/TO take/VB flight/NN ,/, and/CC have/VBP ultimately/RB lost/VBD the/DT power/NN of/IN flying/VBG ./. 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Organs/NNPS ,/, originally/RB formed/VBN by/IN the/DT aid/NN of/IN natural/JJ selection/NN ,/, when/WRB rendered/VBN useless/JJ may/MD well/RB be/VB variable/JJ ,/, for/IN their/PRP$ variations/NNS can/MD no/DT longer/RB be/VB cheeked/VBD by/IN natural/JJ selection/NN ./. All/DT this/DT agrees/VBZ well/RB with/IN what/WP we/PRP see/VB under/IN nature/NN ./. Moreover/RB ,/, at/IN whatever/WDT period/NN of/IN life/NN either/DT disuse/NN or/CC selection/NN reduces/VBZ an/DT organ/NN ,/, and/CC this/DT will/MD generally/RB be/VB when/WRB the/DT being/VBG has/VBZ come/VB to/TO maturity/NN and/CC has/VBZ to/TO exert/VB its/PRP$ full/JJ powers/NNS of/IN action/NN ,/, the/DT principle/NN of/IN inheritance/NN at/IN corresponding/JJ ages/NNS will/MD tend/VB to/TO reproduce/VB the/DT organ/NN in/IN its/PRP$ reduced/VBN state/NN at/IN the/DT same/JJ mature/JJ age/NN ,/, but/CC will/MD seldom/RB effect/NN it/PRP in/IN the/DT embryo/NN ./. 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We/PRP see/VB the/DT full/JJ meaning/NN of/IN the/DT wonderful/JJ fact/NN ,/, which/WDT has/VBZ struck/VBN every/DT traveller/NN ,/, namely/RB ,/, that/IN on/IN the/DT same/JJ continent/NN ,/, under/IN the/DT most/RBS diverse/JJ conditions/NNS ,/, under/IN heat/NN and/CC cold/JJ ,/, on/IN mountain/NN and/CC lowland/NN ,/, on/IN deserts/NNS and/CC marshes/NNS ,/, most/RBS of/IN the/DT inhabitants/NNS within/IN each/DT great/JJ class/NN are/VBP plainly/RB related/VBN ;/: for/IN they/PRP are/VBP the/DT descendants/NNS of/IN the/DT same/JJ progenitors/NNS and/CC early/JJ colonists/NNS ./. 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On/IN this/DT view/NN of/IN migration/NN ,/, with/IN subsequent/JJ modification/NN ,/, we/PRP see/VB why/WRB oceanic/JJ islands/NNS are/VBP inhabited/VBN by/IN only/RB few/JJ species/NN ,/, but/CC of/IN these/DT ,/, why/WRB many/JJ are/VBP peculiar/JJ or/CC endemic/JJ forms/NNS ./. We/PRP clearly/RB see/VB why/WRB species/NN belonging/VBG to/TO those/DT groups/NNS of/IN animals/NNS which/WDT cannot/MD cross/VB wide/JJ spaces/NNS of/IN the/DT ocean/NN ,/, as/IN frogs/NNS and/CC terrestrial/JJ mammals/NNS ,/, do/VBP not/RB inhabit/VBP oceanic/JJ islands/NNS ;/: and/CC why/WRB ,/, on/IN the/DT other/JJ hand/NN ,/, new/JJ and/CC peculiar/JJ species/NN of/IN bats/NNS ,/, animals/NNS which/WDT can/MD traverse/VB the/DT ocean/NN ,/, are/VBP found/VBD on/IN islands/NNS far/RB distant/JJ from/IN any/DT continent/NN ./. 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The/DT Natural/NNP System/NNP is/VBZ a/DT genealogical/JJ arrangement/NN ,/, with/IN the/DT acquired/VBN grades/NNS of/IN difference/NN ,/, marked/VBN by/IN the/DT terms/NNS ,/, varieties/NNS ,/, species/NN ,/, genera/NN ,/, families/NNS ,/, &c/NN ./. ;/: and/CC we/PRP have/VBP to/TO discover/VB the/DT lines/NNS of/IN descent/NN by/IN the/DT most/RBS permanent/JJ characters/NNS whatever/WDT they/PRP may/MD be/VB and/CC of/IN however/RB slight/JJ vital/JJ importance/NN ./. 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On/IN the/DT principle/NN of/IN successive/JJ variations/NNS not/RB always/RB supervening/VBG at/IN an/DT early/JJ age/NN ,/, and/CC being/VBG inherited/VBN at/IN a/DT corresponding/JJ not/RB early/JJ period/NN of/IN life/NN ,/, we/PRP clearly/RB see/VB why/WRB the/DT embryos/NNS of/IN mammals/NNS ,/, birds/NNS ,/, reptiles/NNS ,/, and/CC fishes/NNS should/MD be/VB so/RB closely/RB similar/JJ ,/, and/CC so/RB unlike/IN the/DT adult/NN forms/NNS ./. We/PRP may/MD cease/VB marvelling/VBG at/IN the/DT embryo/NN of/IN an/DT air/NN breathing/NN mammal/NN or/CC bird/NN having/VBG branchial/JJ slits/NNS and/CC arteries/NNS running/VBG in/IN loops/NNS ,/, like/IN those/DT of/IN a/DT fish/NN which/WDT has/VBZ to/TO breathe/VB the/DT air/NN dissolved/VBN in/IN water/NN by/IN the/DT aid/NN of/IN well/RB developed/VBN branchiae/NN ./. Disuse/NNP ,/, aided/VBN sometimes/RB by/IN natural/JJ selection/NN ,/, will/MD often/RB have/VBP reduced/VBN organs/NNS when/WRB rendered/VBN useless/JJ under/IN changed/VBN habits/NNS or/CC conditions/NNS of/IN life/NN ;/: and/CC we/PRP can/MD understand/VB on/IN this/DT view/NN the/DT meaning/NN of/IN rudimentary/JJ organs/NNS ./. But/CC disuse/NN and/CC selection/NN will/MD generally/RB act/NN on/IN each/DT creature/NN ,/, when/WRB it/PRP has/VBZ come/VB to/TO maturity/NN and/CC has/VBZ to/TO play/VB its/PRP$ full/JJ part/NN in/IN the/DT struggle/NN for/IN existence/NN ,/, and/CC will/MD thus/RB have/VBP little/JJ power/NN on/IN an/DT organ/NN during/IN early/JJ life/NN ;/: hence/RB the/DT organ/NN will/MD not/RB be/VB reduced/VBN or/CC rendered/VBN rudimentary/JJ at/IN this/DT early/JJ age/NN ./. 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On/IN the/DT view/NN of/IN each/DT organism/NN with/IN all/DT its/PRP$ separate/JJ parts/NNS having/VBG been/VBN specially/RB created/VBN ,/, how/WRB utterly/RB inexplicable/JJ is/VBZ it/PRP that/IN organs/NNS bearing/VBG the/DT plain/JJ stamp/NN of/IN inutility/NN ,/, such/JJ as/IN the/DT teeth/NNS in/IN the/DT embryonic/JJ calf/NN or/CC the/DT shrivelled/VBN wings/NNS under/IN the/DT soldered/VBN wingcovers/NNS of/IN many/JJ beetles/NNS ,/, should/MD so/RB frequently/RB occur/VB ./. Nature/NNP may/MD be/VB said/VBD to/TO have/VB taken/VBN pains/NNS to/TO reveal/VB her/PRP$ scheme/NN of/IN modification/NN ,/, by/IN means/VBZ of/IN rudimentary/JJ organs/NNS ,/, of/IN embryological/JJ and/CC homologous/RB structures/NNS ,/, but/CC we/PRP are/VBP too/RB blind/JJ to/TO understand/VB her/PRP$ meaning/NN ./. I/PRP have/VBP now/RB recapitulated/VBN the/DT facts/NNS and/CC considerations/NNS which/WDT have/VBP thoroughly/RB convinced/VBN me/PRP that/IN species/NN have/VBP been/VBN modified/VBN ,/, during/IN a/DT long/JJ course/NN of/IN descent/NN ./. This/DT has/VBZ been/VBN effected/VBN chiefly/RB through/IN the/DT natural/JJ selection/NN of/IN numerous/JJ successive/JJ ,/, slight/JJ ,/, favourable/JJ variations/NNS ;/: aided/VBN in/IN an/DT important/JJ manner/NN by/IN the/DT inherited/VBN effects/NNS of/IN the/DT use/NN and/CC disuse/NN of/IN parts/NNS ;/: and/CC in/IN an/DT unimportant/JJ manner/NN ,/, that/IN is/VBZ in/IN relation/NN to/TO adaptive/JJ structures/NNS ,/, whether/IN past/JJ or/CC present/JJ ,/, by/IN the/DT direct/JJ action/NN of/IN external/JJ conditions/NNS ,/, and/CC by/IN variations/NNS which/WDT seem/VB to/TO us/PRP in/IN our/PRP$ ignorance/NN to/TO arise/VB spontaneously/RB ./. It/PRP appears/VBZ that/IN I/PRP formerly/RB underrated/VBN the/DT frequency/NN and/CC value/NN of/IN these/DT latter/NN forms/NNS of/IN variation/NN ,/, as/IN leading/VBG to/TO permanent/JJ modifications/NNS of/IN structure/NN independently/RB of/IN natural/JJ selection/NN ./. But/CC as/IN my/PRP$ conclusions/NNS have/VBP lately/RB been/VBN much/JJ misrepresented/VBD ,/, and/CC it/PRP has/VBZ been/VBN stated/VBN that/IN I/PRP attribute/VBP the/DT modification/NN of/IN species/NN exclusively/RB to/TO natural/JJ selection/NN ,/, I/PRP may/MD be/VB permitted/VBN to/TO remark/NN that/IN in/IN the/DT first/JJ edition/NN of/IN this/DT work/NN ,/, and/CC subsequently/RB ,/, I/PRP placed/VBN in/IN a/DT most/RBS conspicuous/JJ position/NN namely/RB ,/, at/IN the/DT close/VB of/IN the/DT Introduction/NN the/DT following/VBG words/NNS :/: "/" I/PRP am/VBP convinced/VBN that/IN natural/JJ selection/NN has/VBZ been/VBN the/DT main/JJ but/CC not/RB the/DT exclusive/JJ means/VBZ of/IN modification/NN ./. "/" This/DT has/VBZ been/VBN of/IN no/DT avail/NN ./. Great/NNP is/VBZ the/DT power/NN of/IN steady/JJ misrepresentation/NN ;/: but/CC the/DT history/NN of/IN science/NN shows/VBZ that/IN fortunately/RB this/DT power/NN does/VBZ not/RB long/JJ endure/VB ./. It/PRP can/MD hardly/RB be/VB supposed/VBN that/IN a/DT false/JJ theory/NN would/MD explain/VB ,/, in/IN so/RB satisfactory/JJ a/DT manner/NN as/IN does/VBZ the/DT theory/NN of/IN natural/JJ selection/NN ,/, the/DT several/JJ large/JJ classes/NNS of/IN facts/NNS above/IN specified/VBN ./. It/PRP has/VBZ recently/RB been/VBN objected/VBD that/IN this/DT is/VBZ an/DT unsafe/JJ method/NN of/IN arguing/VBG ;/: but/CC it/PRP is/VBZ a/DT method/NN used/VBN in/IN judging/VBG of/IN the/DT common/JJ events/NNS of/IN life/NN ,/, and/CC has/VBZ often/RB been/VBN used/VBN by/IN the/DT greatest/JJS natural/JJ philosophers/NNS ./. The/DT undulatory/JJ theory/NN of/IN light/NN has/VBZ thus/RB been/VBN arrived/VBD at/IN ;/: and/CC the/DT belief/NN in/IN the/DT revolution/NN of/IN the/DT earth/NN on/IN its/PRP$ own/JJ axis/NN was/VBD until/IN lately/RB supported/VBN by/IN hardly/RB any/DT direct/JJ evidence/NN ./. It/PRP is/VBZ no/DT valid/JJ objection/NN that/IN science/NN as/IN yet/RB throws/VBZ no/DT light/NN on/IN the/DT far/RB higher/JJR problem/NN of/IN the/DT essence/NN or/CC origin/NN of/IN life/NN ./. Who/WP can/MD explain/VB what/WP is/VBZ the/DT essence/NN of/IN the/DT attraction/NN of/IN gravity/NN ?/. No/DT one/CD now/RB objects/NNS to/TO following/VBG out/IN the/DT results/NNS consequent/JJ on/IN this/DT unknown/JJ element/NN of/IN attraction/NN ;/: notwithstanding/IN that/IN Leibnitz/NNP formerly/RB accused/VBN Newton/NNP of/IN introducing/VBG "/" occult/NN qualities/NNS and/CC miracles/NNS into/IN philosophy/NN ./. "/" I/PRP see/VB no/DT good/JJ reason/NN why/WRB the/DT views/NNS given/VBN in/IN this/DT volume/NN should/MD shock/NN the/DT religious/JJ feelings/NNS of/IN any/DT one/CD ./. It/PRP is/VBZ satisfactory/JJ ,/, as/IN showing/VBG how/WRB transient/JJ such/JJ impressions/NNS are/VBP ,/, to/TO remember/VB that/IN the/DT greatest/JJS discovery/NN ever/RB made/VBN by/IN man/NN ,/, namely/RB ,/, the/DT law/NN of/IN the/DT attraction/NN of/IN gravity/NN ,/, was/VBD also/RB attacked/VBN by/IN Leibnitz/NNP ,/, "/" as/IN subversive/JJ of/IN natural/JJ ,/, and/CC inferentially/RB of/IN revealed/VBD ,/, religion/NN ./. 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It/PRP cannot/MD be/VB asserted/VBD that/IN organic/JJ beings/NNS in/IN a/DT state/NN of/IN nature/NN are/VBP subject/NN to/TO no/DT variation/NN ;/: it/PRP cannot/MD be/VB proved/VBD that/IN the/DT amount/NN of/IN variation/NN in/IN the/DT course/NN of/IN long/JJ ages/NNS is/VBZ a/DT limited/JJ quality/NN ;/: no/DT clear/JJ distinction/NN has/VBZ been/VBN ,/, or/CC can/MD be/VB ,/, drawn/VBN between/IN species/NN and/CC well/RB marked/VBN varieties/NNS ./. It/PRP cannot/MD be/VB maintained/VBN that/IN species/NN when/WRB intercrossed/VBN are/VBP invariably/RB sterile/JJ ,/, and/CC varieties/NNS invariably/RB fertile/JJ ;/: or/CC that/IN sterility/NN is/VBZ a/DT special/JJ endowment/NN and/CC sign/NN of/IN creation/NN ./. The/DT belief/NN that/IN species/NN were/VBD immutable/JJ productions/NNS was/VBD almost/RB unavoidable/JJ as/IN long/JJ as/IN the/DT history/NN of/IN the/DT world/NN was/VBD thought/VBD to/TO be/VB of/IN short/JJ duration/NN ;/: and/CC now/RB that/IN we/PRP have/VBP acquired/VBN some/DT idea/NN of/IN the/DT lapse/NN of/IN time/NN ,/, we/PRP are/VBP too/RB apt/JJ to/TO assume/VB ,/, without/IN proof/NN ,/, that/IN the/DT geological/JJ record/NN is/VBZ so/RB perfect/JJ that/IN it/PRP would/MD have/VB afforded/VBN us/PRP plain/JJ evidence/NN of/IN the/DT mutation/NN of/IN species/NN ,/, if/IN they/PRP had/VBD undergone/VBN mutation/NN ./. But/CC the/DT chief/JJ cause/NN of/IN our/PRP$ natural/JJ unwillingness/NN to/TO admit/VB that/IN one/CD species/NN has/VBZ given/VBN birth/NN to/TO clear/JJ and/CC distinct/JJ species/NN ,/, is/VBZ that/IN we/PRP are/VBP always/RB slow/JJ in/IN admitting/VBG great/JJ changes/NNS of/IN which/WDT we/PRP do/VBP not/RB see/VB the/DT steps/NNS ./. The/DT difficulty/NN is/VBZ the/DT same/JJ as/IN that/IN felt/VBD by/IN so/RB many/JJ geologists/NNS ,/, when/WRB Lyell/NNP first/JJ insisted/VBD that/IN long/JJ lines/NNS of/IN inland/RB cliffs/NNS had/VBD been/VBN formed/VBN ,/, and/CC great/JJ valleys/NNS excavated/VBN ,/, by/IN the/DT agencies/NNS which/WDT we/PRP see/VB still/RB at/IN work/NN ./. The/DT mind/NN cannot/MD possibly/RB grasp/VB the/DT full/JJ meaning/NN of/IN the/DT term/NN of/IN even/RB a/DT million/CD years/NNS ;/: it/PRP cannot/MD add/VB up/IN and/CC perceive/VB the/DT full/JJ effects/NNS of/IN many/JJ slight/JJ variations/NNS ,/, accumulated/VBN during/IN an/DT almost/RB infinite/JJ number/NN of/IN generations/NNS ./. Although/IN I/PRP am/VBP fully/RB convinced/VBN of/IN the/DT truth/NN of/IN the/DT views/NNS given/VBN in/IN this/DT volume/NN under/IN the/DT form/NN of/IN an/DT abstract/JJ ,/, I/PRP by/IN no/DT means/VBZ expect/VBP to/TO convince/VB experienced/VBN naturalists/NNS whose/WP$ minds/NNS are/VBP stocked/VBN with/IN a/DT multitude/NN of/IN facts/NNS all/DT viewed/VBN ,/, during/IN a/DT long/JJ course/NN of/IN years/NNS ,/, from/IN a/DT point/NN of/IN view/NN directly/RB opposite/JJ to/TO mine/NN ./. It/PRP is/VBZ so/RB easy/JJ to/TO hide/VB our/PRP$ ignorance/NN under/IN such/JJ expressions/NNS as/IN the/DT "/" plan/NN of/IN creation/NN "/" or/CC "/" unity/NN of/IN design/NN ,/, "/" &c/NN ./. ,/, and/CC to/TO think/VB that/IN we/PRP give/VB an/DT explanation/NN when/WRB we/PRP only/RB restate/VB a/DT fact/NN ./. Any/DT one/CD whose/WP$ disposition/NN leads/VBZ him/PRP to/TO attach/VB more/JJR weight/NN to/TO unexplained/JJ difficulties/NNS than/IN to/TO the/DT explanation/NN of/IN a/DT certain/JJ number/NN of/IN facts/NNS will/MD certainly/RB reject/VB the/DT theory/NN ./. A/DT few/JJ naturalists/NNS ,/, endowed/VBN with/IN much/JJ flexibility/NN of/IN mind/NN ,/, and/CC who/WP have/VBP already/RB begun/VBN to/TO doubt/NN the/DT immutability/NN of/IN species/NN ,/, may/MD be/VB influenced/VBN by/IN this/DT volume/NN ;/: but/CC I/PRP look/VB with/IN confidence/NN to/TO the/DT future/NN ,/, to/TO young/JJ and/CC rising/VBG naturalists/NNS ,/, who/WP will/MD be/VB able/JJ to/TO view/NN both/DT sides/NNS of/IN the/DT question/NN with/IN impartiality/NN ./. Whoever/WP is/VBZ led/VBN to/TO believe/VB that/IN species/NN are/VBP mutable/JJ will/MD do/VB good/JJ service/NN by/IN conscientiously/RB expressing/VBG his/PRP$ conviction/NN ;/: for/IN thus/RB only/RB can/MD the/DT load/NN of/IN prejudice/NN by/IN which/WDT this/DT subject/NN is/VBZ overwhelmed/VBN be/VB removed/VBN ./. Several/JJ eminent/JJ naturalists/NNS have/VBP of/IN late/JJ published/VBN their/PRP$ belief/NN that/IN a/DT multitude/NN of/IN reputed/VBN species/NN in/IN each/DT genus/NN are/VBP not/RB real/JJ species/NN ;/: but/CC that/IN other/JJ species/NN are/VBP real/JJ ,/, that/IN is/VBZ ,/, have/VBP been/VBN independently/RB created/VBN ./. This/DT seems/VBZ to/TO me/PRP a/DT strange/JJ conclusion/NN to/TO arrive/VB at/IN ./. They/PRP admit/VB that/IN a/DT multitude/NN of/IN forms/NNS ,/, which/WDT till/IN lately/RB they/PRP themselves/PRP thought/VBD were/VBD special/JJ creations/NNS ,/, and/CC which/WDT are/VBP still/RB thus/RB looked/VBD at/IN by/IN the/DT majority/NN of/IN naturalists/NNS ,/, and/CC which/WDT consequently/RB have/VBP all/DT the/DT external/JJ characteristic/JJ features/NNS of/IN true/JJ species/NN ,/, they/PRP admit/VB that/IN these/DT have/VBP been/VBN produced/VBN by/IN variation/NN ,/, but/CC they/PRP refuse/VB to/TO extend/VB the/DT same/JJ view/NN to/TO other/JJ and/CC slightly/RB different/JJ forms/NNS ./. Nevertheless/RB they/PRP do/VBP not/RB pretend/VB that/IN they/PRP can/MD define/VB ,/, or/CC even/RB conjecture/NN ,/, which/WDT are/VBP the/DT created/VBN forms/NNS of/IN life/NN ,/, and/CC which/WDT are/VBP those/DT produced/VBN by/IN secondary/JJ laws/NNS ./. They/PRP admit/VB variation/NN as/IN a/DT vera/NN causa/NN in/IN one/CD case/NN ,/, they/PRP arbitrarily/RB reject/VB it/PRP in/IN another/DT ,/, without/IN assigning/VBG any/DT distinction/NN in/IN the/DT two/CD cases/NNS ./. The/DT day/NN will/MD come/VB when/WRB this/DT will/MD be/VB given/VBN as/IN a/DT curious/JJ illustration/NN of/IN the/DT blindness/NN of/IN preconceived/JJ opinion/NN ./. These/DT authors/NNS seem/VB no/DT more/JJR startled/VBN at/IN a/DT miraculous/JJ act/NN of/IN creation/NN than/IN at/IN an/DT ordinary/JJ birth/NN ./. But/CC do/VBP they/PRP really/RB believe/VBP that/IN at/IN innumerable/JJ periods/NNS in/IN the/DT earth's/NNS history/NN certain/JJ elemental/JJ atoms/NNS have/VBP been/VBN commanded/VBD suddenly/RB to/TO flash/NN into/IN living/VBG tissues/NNS ?/. Do/VBP they/PRP believe/VBP that/IN at/IN each/DT supposed/VBN act/NN of/IN creation/NN one/CD individual/JJ or/CC many/JJ were/VBD produced/VBN ?/. Were/VBD all/DT the/DT infinitely/RB numerous/JJ kinds/NNS of/IN animals/NNS and/CC plants/NNS created/VBN as/IN eggs/NNS or/CC seed/NN ,/, or/CC as/IN full/JJ grown/VBN ?/. and/CC in/IN the/DT case/NN of/IN mammals/NNS ,/, were/VBD they/PRP created/VBN bearing/VBG the/DT false/JJ marks/NNS of/IN nourishment/NN from/IN the/DT mother's/NNS womb/NN ?/. Undoubtedly/RB some/DT of/IN these/DT same/JJ questions/NNS cannot/MD be/VB answered/VBD by/IN those/DT who/WP believe/VBP in/IN the/DT appearance/NN or/CC creation/NN of/IN only/RB a/DT few/JJ forms/NNS of/IN life/NN ,/, or/CC of/IN some/DT one/CD form/NN alone/RB ./. It/PRP has/VBZ been/VBN maintained/VBN by/IN several/JJ authors/NNS that/IN it/PRP is/VBZ as/IN easy/JJ to/TO believe/VB in/IN the/DT creation/NN of/IN a/DT million/CD beings/NNS as/IN of/IN one/CD ;/: but/CC Maupertuis'/NNP philosophical/JJ axiom/NN "/" of/IN least/JJS action/NN "/" leads/VBZ the/DT mind/NN more/JJR willingly/RB to/TO admit/VB the/DT smaller/JJR number/NN ;/: and/CC certainly/RB we/PRP ought/MD not/RB to/TO believe/VB that/IN innumerable/JJ beings/NNS within/IN each/DT great/JJ class/NN have/VBP been/VBN created/VBN with/IN plain/JJ ,/, but/CC deceptive/JJ ,/, marks/NNS of/IN descent/NN from/IN a/DT single/JJ parent/NN ./. As/IN a/DT record/NN of/IN a/DT former/JJ state/NN of/IN things/NNS ,/, I/PRP have/VBP retained/VBN in/IN the/DT foregoing/NN paragraphs/NNS ,/, and/CC elsewhere/RB ,/, several/JJ sentences/NNS which/WDT imply/VB that/IN naturalists/NNS believe/VBP in/IN the/DT separate/JJ creation/NN of/IN each/DT species/NN ;/: and/CC I/PRP have/VBP been/VBN much/JJ censured/VBD for/IN having/VBG thus/RB expressed/VBN myself/PRP ./. But/CC undoubtedly/RB this/DT was/VBD the/DT general/JJ belief/NN when/WRB the/DT first/JJ edition/NN of/IN the/DT present/JJ work/NN appeared/VBD ./. I/PRP formerly/RB spoke/VBD to/TO very/RB many/JJ naturalists/NNS on/IN the/DT subject/NN of/IN evolution/NN ,/, and/CC never/RB once/RB met/VBD with/IN any/DT sympathetic/JJ agreement/NN ./. It/PRP is/VBZ probable/JJ that/IN some/DT did/VBD then/RB believe/VBP in/IN evolution/NN ,/, but/CC they/PRP were/VBD either/DT silent/JJ ,/, or/CC expressed/VBN themselves/PRP so/RB ambiguously/RB that/IN it/PRP was/VBD not/RB easy/JJ to/TO understand/VB their/PRP$ meaning/NN ./. Now/RB things/NNS are/VBP wholly/RB changed/VBN ,/, and/CC almost/RB every/DT naturalist/NN admits/VBZ the/DT great/JJ principle/NN of/IN evolution/NN ./. There/EX are/VBP ,/, however/RB ,/, some/DT who/WP still/RB think/VBP that/IN species/NN have/VBP suddenly/RB given/VBN birth/NN ,/, through/IN quite/RB unexplained/JJ means/VBZ ,/, to/TO new/JJ and/CC totally/RB different/JJ forms/NNS :/: but/CC ,/, as/IN I/PRP have/VBP attempted/VBD to/TO show/NN ,/, weighty/JJ evidence/NN can/MD be/VB opposed/VBN to/TO the/DT admission/NN of/IN great/JJ and/CC abrupt/JJ modifications/NNS ./. Under/IN a/DT scientific/JJ point/NN of/IN view/NN ,/, and/CC as/IN leading/VBG to/TO further/JJR investigation/NN ,/, but/CC little/JJ advantage/NN is/VBZ gained/VBN by/IN believing/VBG that/IN new/JJ forms/NNS are/VBP suddenly/RB developed/VBN in/IN an/DT inexplicable/JJ manner/NN from/IN old/JJ and/CC widely/RB different/JJ forms/NNS ,/, over/IN the/DT old/JJ belief/NN in/IN the/DT creation/NN of/IN species/NN from/IN the/DT dust/NN of/IN the/DT earth/NN ./. It/PRP may/MD be/VB asked/VBD how/WRB far/RB I/PRP extend/VB the/DT doctrine/NN of/IN the/DT modification/NN of/IN species/NN ./. The/DT question/NN is/VBZ difficult/JJ to/TO answer/NN ,/, because/IN the/DT more/JJR distinct/JJ the/DT forms/NNS are/VBP which/WDT we/PRP consider/VB ,/, by/IN so/RB much/JJ the/DT arguments/NNS in/IN favour/NN of/IN community/NN of/IN descent/NN become/VB fewer/JJR in/IN number/NN and/CC less/JJR in/IN force/NN ./. But/CC some/DT arguments/NNS of/IN the/DT greatest/JJS weight/NN extend/VB very/RB far/RB ./. All/DT the/DT members/NNS of/IN whole/JJ classes/NNS are/VBP connected/VBN together/RB by/IN a/DT chain/NN of/IN affinities/NNS ,/, and/CC all/DT can/MD be/VB classed/VBN on/IN the/DT same/JJ principle/NN ,/, in/IN groups/NNS subordinate/JJ to/TO groups/NNS ./. Fossil/NNP remains/VBZ sometimes/RB tend/VBP to/TO fill/VB up/IN very/RB wide/JJ intervals/NNS between/IN existing/VBG orders/NNS ./. Organs/NNPS in/IN a/DT rudimentary/JJ condition/NN plainly/RB show/NN that/IN an/DT early/JJ progenitor/NN had/VBD the/DT organ/NN in/IN a/DT fully/RB developed/VBN condition/NN ;/: and/CC this/DT in/IN some/DT cases/NNS implies/VBZ an/DT enormous/JJ amount/NN of/IN modification/NN in/IN the/DT descendants/NNS ./. Throughout/IN whole/JJ classes/NNS various/JJ structures/NNS are/VBP formed/VBN on/IN the/DT same/JJ pattern/NN ,/, and/CC at/IN a/DT very/RB early/JJ age/NN the/DT embryos/NNS closely/RB resemble/VB each/DT other/JJ ./. Therefore/RB I/PRP cannot/MD doubt/NN that/IN the/DT theory/NN of/IN descent/NN with/IN modification/NN embraces/VBZ all/DT the/DT members/NNS of/IN the/DT same/JJ great/JJ class/NN or/CC kingdom/NN ./. I/PRP believe/VBP that/IN animals/NNS are/VBP descended/VBD from/IN at/IN most/RBS only/RB four/CD or/CC five/CD progenitors/NNS ,/, and/CC plants/NNS from/IN an/DT equal/JJ or/CC lesser/JJR number/NN ./. Analogy/NNP would/MD lead/VB me/PRP one/CD step/NN farther/RB ,/, namely/RB ,/, to/TO the/DT belief/NN that/IN all/DT animals/NNS and/CC plants/NNS are/VBP descended/VBD from/IN some/DT one/CD prototype/NN ./. But/CC analogy/NN may/MD be/VB a/DT deceitful/JJ guide/NN ./. Nevertheless/RB all/DT living/VBG things/NNS have/VBP much/JJ in/IN common/JJ ,/, in/IN their/PRP$ chemical/NN composition/NN ,/, their/PRP$ cellular/JJ structure/NN ,/, their/PRP$ laws/NNS of/IN growth/NN ,/, and/CC their/PRP$ liability/NN to/TO injurious/JJ influences/NNS ./. We/PRP see/VB this/DT even/RB in/IN so/RB trifling/JJ a/DT fact/NN as/IN that/IN the/DT same/JJ poison/NN often/RB similarly/RB affects/VBZ plants/NNS and/CC animals/NNS ;/: or/CC that/IN the/DT poison/NN secreted/VBN by/IN the/DT gallfly/RB produces/VBZ monstrous/JJ growths/NNS on/IN the/DT wild/JJ rose/VBD or/CC oak/NN tree/NN ./. With/IN all/DT organic/JJ beings/NNS excepting/VBG perhaps/RB some/DT of/IN the/DT very/RB lowest/JJS ,/, sexual/JJ production/NN seems/VBZ to/TO be/VB essentially/RB similar/JJ ./. With/IN all/DT ,/, as/IN far/RB as/IN is/VBZ at/IN present/JJ known/VBN the/DT germinal/JJ vesicle/NN is/VBZ the/DT same/JJ ;/: so/RB that/IN all/DT organisms/NNS start/VB from/IN a/DT common/JJ origin/NN ./. If/IN we/PRP look/VB even/RB to/TO the/DT two/CD main/JJ divisions/NNS namely/RB ,/, to/TO the/DT animal/NN and/CC vegetable/NN kingdoms/NNS certain/JJ low/JJ forms/NNS are/VBP so/RB far/RB intermediate/JJ in/IN character/NN that/IN naturalists/NNS have/VBP disputed/VBN to/TO which/WDT kingdom/NN they/PRP should/MD be/VB referred/VBN ./. As/IN Professor/NNP Asa/NNP Gray/NNP has/VBZ remarked/VBN ,/, "/" The/DT spores/NNS and/CC other/JJ reproductive/JJ bodies/NNS of/IN many/JJ of/IN the/DT lower/JJR algae/NNS may/MD claim/NN to/TO have/VB first/JJ a/DT characteristically/RB animal/NN ,/, and/CC then/RB an/DT unequivocally/RB vegetable/NN existence/NN ./. "/" Therefore/RB ,/, on/IN the/DT principle/NN of/IN natural/JJ selection/NN with/IN divergence/NN of/IN character/NN ,/, it/PRP does/VBZ not/RB seem/VB incredible/JJ that/IN ,/, from/IN such/JJ low/JJ and/CC intermediate/JJ form/NN ,/, both/DT animals/NNS and/CC plants/NNS may/MD have/VB been/VBN developed/VBN ;/: and/CC ,/, if/IN we/PRP admit/VB this/DT ,/, we/PRP must/MD likewise/RB admit/VB that/IN all/DT the/DT organic/JJ beings/NNS which/WDT have/VBP ever/RB lived/VBD on/IN this/DT earth/NN may/MD be/VB descended/VBD from/IN some/DT one/CD primordial/JJ form/NN ./. But/CC this/DT inference/NN is/VBZ chiefly/RB grounded/VBN on/IN analogy/NN and/CC it/PRP is/VBZ immaterial/JJ whether/IN or/CC not/RB it/PRP be/VB accepted/VBN ./. No/DT doubt/NN it/PRP is/VBZ possible/JJ ,/, as/IN Mr/NNP ./. G/NN ./. H/NNP ./. Lewes/NNP has/VBZ urged/VBN ,/, that/IN at/IN the/DT first/JJ commencement/NN of/IN life/NN many/JJ different/JJ forms/NNS were/VBD evolved/VBN ;/: but/CC if/IN so/RB we/PRP may/MD conclude/VB that/IN only/RB a/DT very/RB few/JJ have/VBP left/VBN modified/VBN descendants/NNS ./. For/IN ,/, as/IN I/PRP have/VBP recently/RB remarked/VBD in/IN regard/NN to/TO the/DT members/NNS of/IN each/DT great/JJ kingdom/NN ,/, such/JJ as/IN the/DT Vertebrata/NNP ,/, Articulata/NNP ,/, &c/NN ./. ,/, we/PRP have/VBP distinct/JJ evidence/NN in/IN their/PRP$ embryological/JJ homologous/RB and/CC rudimentary/JJ structures/NNS that/IN within/IN each/DT kingdom/NN all/DT the/DT members/NNS are/VBP descended/VBD from/IN a/DT single/JJ progenitor/NN ./. When/WRB the/DT views/NNS advanced/VBD by/IN me/PRP in/IN this/DT volume/NN ,/, and/CC by/IN Mr/NNP ./. Wallace/NNP ,/, or/CC when/WRB analogous/JJ views/NNS on/IN the/DT origin/NN of/IN species/NN are/VBP generally/RB admitted/VBD ,/, we/PRP can/MD dimly/RB foresee/VBP that/IN there/EX will/MD be/VB a/DT considerable/JJ revolution/NN in/IN natural/JJ history/NN ./. Systematists/NNS will/MD be/VB able/JJ to/TO pursue/VB their/PRP$ labours/NNS as/IN at/IN present/JJ ;/: but/CC they/PRP will/MD not/RB be/VB incessantly/RB haunted/VBN by/IN the/DT shadowy/JJ doubt/NN whether/IN this/DT or/CC that/IN form/NN be/VB a/DT true/JJ species/NN ./. This/DT ,/, I/PRP feel/VB sure/JJ and/CC I/PRP speak/VB after/IN experience/NN ,/, will/MD be/VB no/DT slight/JJ relief/NN ./. The/DT endless/JJ disputes/NNS whether/IN or/CC not/RB some/DT fifty/CD species/NN of/IN British/JJ brambles/NNS are/VBP good/JJ species/NN will/MD cease/VB ./. Systematists/NNS will/MD have/VB only/RB to/TO decide/VB (/( not/RB that/IN this/DT will/MD be/VB easy/JJ )/SYM whether/IN any/DT form/NN be/VB sufficiently/RB constant/JJ and/CC distinct/JJ from/IN other/JJ forms/NNS ,/, to/TO be/VB capable/JJ of/IN definition/NN ;/: and/CC if/IN definable/JJ ,/, whether/IN the/DT differences/NNS be/VB sufficiently/RB important/JJ to/TO deserve/VB a/DT specific/JJ name/NN ./. This/DT latter/NN point/NN will/MD become/VB a/DT far/RB more/JJR essential/JJ consideration/NN than/IN it/PRP is/VBZ at/IN present/JJ ;/: for/IN differences/NNS ,/, however/RB slight/JJ ,/, between/IN any/DT two/CD forms/NNS if/IN not/RB blended/JJ by/IN intermediate/JJ gradations/NNS ,/, are/VBP looked/VBD at/IN by/IN most/RBS naturalists/NNS as/IN sufficient/JJ to/TO raise/VB both/DT forms/NNS to/TO the/DT rank/NN of/IN species/NN ./. 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The/DT terms/NNS used/VBN by/IN naturalists/NNS ,/, of/IN affinity/NN ,/, relationship/NN ,/, community/NN of/IN type/NN ,/, paternity/NN ,/, morphology/NN ,/, adaptive/JJ characters/NNS ,/, rudimentary/JJ and/CC aborted/JJ organs/NNS ,/, &c/NN ./. ,/, will/MD cease/VB to/TO be/VB metaphorical/JJ ,/, and/CC will/MD have/VB a/DT plain/JJ signification/NN ./. When/WRB we/PRP no/DT longer/RB look/VB at/IN an/DT organic/JJ being/VBG as/IN a/DT savage/JJ looks/VBZ at/IN a/DT ship/NN ,/, as/IN something/NN wholly/RB beyond/IN his/PRP$ comprehension/NN ;/: when/WRB we/PRP regard/NN every/DT production/NN of/IN nature/NN as/IN one/CD which/WDT has/VBZ had/VBD a/DT long/JJ history/NN ;/: when/WRB we/PRP contemplate/VB every/DT complex/JJ structure/NN and/CC instinct/NN as/IN the/DT summing/VBG up/IN of/IN many/JJ contrivances/NNS ,/, each/DT useful/JJ to/TO the/DT possessor/NN ,/, in/IN the/DT same/JJ way/NN as/IN any/DT great/JJ mechanical/JJ invention/NN is/VBZ the/DT summing/VBG up/IN of/IN the/DT labour/NN ,/, the/DT experience/NN ,/, the/DT reason/NN ,/, and/CC even/RB the/DT blunders/NNS of/IN numerous/JJ workmen/NNS ;/: when/WRB we/PRP thus/RB view/NN each/DT organic/JJ being/VBG ,/, how/WRB far/RB more/JJR interesting/JJ I/PRP speak/VB from/IN experience/NN does/VBZ the/DT study/NN of/IN natural/JJ history/NN become!/NN A/DT grand/JJ and/CC almost/RB untrodden/JJ field/NN of/IN inquiry/NN will/MD be/VB opened/VBD ,/, on/IN the/DT causes/NNS and/CC laws/NNS of/IN variation/NN ,/, on/IN correlation/NN ,/, on/IN the/DT effects/NNS of/IN use/NN and/CC disuse/NN ,/, on/IN the/DT direct/JJ action/NN of/IN external/JJ conditions/NNS ,/, and/CC so/RB forth/RB ./. The/DT study/NN of/IN domestic/JJ productions/NNS will/MD rise/NN immensely/RB in/IN value/NN ./. A/DT new/JJ variety/NN raised/VBN by/IN man/NN will/MD be/VB a/DT more/JJR important/JJ and/CC interesting/JJ subject/NN for/IN study/NN than/IN one/CD more/JJR species/NN added/VBD to/TO the/DT infinitude/NN of/IN already/RB recorded/VBN species/NN ./. Our/PRP$ classifications/NNS will/MD come/VB to/TO be/VB ,/, as/IN far/RB as/IN they/PRP can/MD be/VB so/RB made/VBN ,/, genealogies/NNS ;/: and/CC will/MD then/RB truly/RB give/VB what/WP may/MD be/VB called/VBN the/DT plan/NN of/IN creation/NN ./. The/DT rules/NNS for/IN classifying/VBG will/MD no/DT doubt/NN become/VB simpler/JJR when/WRB we/PRP have/VBP a/DT definite/JJ object/NN in/IN view/NN ./. We/PRP possess/VBP no/DT pedigrees/NNS or/CC armorial/JJ bearings/NNS ;/: and/CC we/PRP have/VBP to/TO discover/VB and/CC trace/NN the/DT many/JJ diverging/VBG lines/NNS of/IN descent/NN in/IN our/PRP$ natural/JJ genealogies/NNS ,/, by/IN characters/NNS of/IN any/DT kind/NN which/WDT have/VBP long/JJ been/VBN inherited/VBN ./. Rudimentary/NNP organs/NNS will/MD speak/VB infallibly/RB with/IN respect/NN to/TO the/DT nature/NN of/IN long/JJ lost/VBD structures/NNS ./. Species/NNP and/CC groups/NNS of/IN species/NN which/WDT are/VBP called/VBN aberrant/JJ ,/, and/CC which/WDT may/MD fancifully/RB be/VB called/VBN living/VBG fossils/NNS ,/, will/MD aid/NN us/PRP in/IN forming/VBG a/DT picture/NN of/IN the/DT ancient/JJ forms/NNS of/IN life/NN ./. Embryology/NNP will/MD often/RB reveal/VB to/TO us/PRP the/DT structure/NN ,/, in/IN some/DT degree/NN obscured/VBN ,/, of/IN the/DT prototype/NN of/IN each/DT great/JJ class/NN ./. When/WRB we/PRP feel/VB assured/VBN that/IN all/DT the/DT individuals/NNS of/IN the/DT same/JJ species/NN ,/, and/CC all/DT the/DT closely/RB allied/VBN species/NN of/IN most/RBS genera/NN ,/, have/VBP within/IN a/DT not/RB very/RB remote/JJ period/NN descended/VBD from/IN one/CD parent/NN ,/, and/CC have/VBP migrated/VBN from/IN some/DT one/CD birth/NN place/NN ;/: and/CC when/WRB we/PRP better/JJR know/VB the/DT many/JJ means/VBZ of/IN migration/NN ,/, then/RB ,/, by/IN the/DT light/NN which/WDT geology/NN now/RB throws/VBZ ,/, and/CC will/MD continue/VB to/TO throw/VB ,/, on/IN former/JJ changes/NNS of/IN climate/NN and/CC of/IN the/DT level/NN of/IN the/DT land/NN ,/, we/PRP shall/MD surely/RB be/VB enabled/VBD to/TO trace/NN in/IN an/DT admirable/JJ manner/NN the/DT former/JJ migrations/NNS of/IN the/DT inhabitants/NNS of/IN the/DT whole/JJ world/NN ./. Even/RB at/IN present/JJ ,/, by/IN comparing/VBG the/DT differences/NNS between/IN the/DT inhabitants/NNS of/IN the/DT sea/NN on/IN the/DT opposite/JJ sides/NNS of/IN a/DT continent/NN ,/, and/CC the/DT nature/NN of/IN the/DT various/JJ inhabitants/NNS on/IN that/IN continent/NN ,/, in/IN relation/NN to/TO their/PRP$ apparent/JJ means/VBZ of/IN immigration/NN ,/, some/DT light/NN can/MD be/VB thrown/VBN on/IN ancient/JJ geography/NN ./. The/DT noble/JJ science/NN of/IN Geology/NNP loses/VBZ glory/NN from/IN the/DT extreme/JJ imperfection/NN of/IN the/DT record/NN ./. The/DT crust/NN of/IN the/DT earth/NN with/IN its/PRP$ imbedded/VBN remains/VBZ must/MD not/RB be/VB looked/VBD at/IN as/IN a/DT well/RB filled/VBN museum/NN ,/, but/CC as/IN a/DT poor/JJ collection/NN made/VBN at/IN hazard/NN and/CC at/IN rare/JJ intervals/NNS ./. The/DT accumulation/NN of/IN each/DT great/JJ fossiliferous/JJ formation/NN will/MD be/VB recognised/VBD as/IN having/VBG depended/VBD on/IN an/DT unusual/JJ concurrence/NN of/IN favourable/JJ circumstances/NNS ,/, and/CC the/DT blank/JJ intervals/NNS between/IN the/DT successive/JJ stages/NNS as/IN having/VBG been/VBN of/IN vast/JJ duration/NN ./. But/CC we/PRP shall/MD be/VB able/JJ to/TO gauge/NN with/IN some/DT security/NN the/DT duration/NN of/IN these/DT intervals/NNS by/IN a/DT comparison/NN of/IN the/DT preceding/VBG and/CC succeeding/VBG organic/JJ forms/NNS ./. We/PRP must/MD be/VB cautious/JJ in/IN attempting/VBG to/TO correlate/VB as/IN strictly/RB contemporaneous/JJ two/CD formations/NNS ,/, which/WDT do/VBP not/RB include/VBP many/JJ identical/JJ species/NN ,/, by/IN the/DT general/JJ succession/NN of/IN the/DT forms/NNS of/IN life/NN ./. As/IN species/NN are/VBP produced/VBN and/CC exterminated/VBN by/IN slowly/RB acting/VBG and/CC still/RB existing/VBG causes/NNS ,/, and/CC not/RB by/IN miraculous/JJ acts/NNS of/IN creation/NN ;/: and/CC as/IN the/DT most/RBS important/JJ of/IN all/DT causes/NNS of/IN organic/JJ change/NN is/VBZ one/CD which/WDT is/VBZ almost/RB independent/JJ of/IN altered/VBN and/CC perhaps/RB suddenly/RB altered/VBN physical/JJ conditions/NNS ,/, namely/RB ,/, the/DT mutual/JJ relation/NN of/IN organism/NN to/TO organism/NN ,/, the/DT improvement/NN of/IN one/CD organism/NN entailing/VBG the/DT improvement/NN or/CC the/DT extermination/NN of/IN others/NNS ;/: it/PRP follows/VBZ ,/, that/IN the/DT amount/NN of/IN organic/JJ change/NN in/IN the/DT fossils/NNS of/IN consecutive/JJ formations/NNS probably/RB serves/VBZ as/IN a/DT fair/JJ measure/NN of/IN the/DT relative/JJ though/IN not/RB actual/JJ lapse/NN of/IN time/NN ./. A/DT number/NN of/IN species/NN ,/, however/RB ,/, keeping/VBG in/IN a/DT body/NN might/MD remain/VB for/IN a/DT long/JJ period/NN unchanged/JJ ,/, whilst/NN within/IN the/DT same/JJ period/NN several/JJ of/IN these/DT species/NN by/IN migrating/VBG into/IN new/JJ countries/NNS and/CC coming/VBG into/IN competition/NN with/IN foreign/JJ associates/NNS ,/, might/MD become/VB modified/VBN ;/: so/RB that/IN we/PRP must/MD not/RB overrate/VB the/DT accuracy/NN of/IN organic/JJ change/NN as/IN a/DT measure/NN of/IN time/NN ./. In/IN the/DT future/NN I/PRP see/VB open/JJ fields/NNS for/IN far/RB more/JJR important/JJ researches/VBZ ./. Psychology/NNP will/MD be/VB securely/RB based/VBN on/IN the/DT foundation/NN already/RB well/RB laid/VBN by/IN Mr/NNP ./. Herbert/NNP Spencer/NNP ,/, that/IN of/IN the/DT necessary/JJ acquirement/NN of/IN each/DT mental/JJ power/NN and/CC capacity/NN by/IN gradation/NN ./. Much/RB light/NN will/MD be/VB thrown/VBN on/IN the/DT origin/NN of/IN man/NN and/CC his/PRP$ history/NN ./. Authors/NNS of/IN the/DT highest/JJS eminence/NN seem/VB to/TO be/VB fully/RB satisfied/VBN with/IN the/DT view/NN that/IN each/DT species/NN has/VBZ been/VBN independently/RB created/VBN ./. To/TO my/PRP$ mind/NN it/PRP accords/NNS better/JJR with/IN what/WP we/PRP know/VB of/IN the/DT laws/NNS impressed/VBN on/IN matter/NN by/IN the/DT Creator/NNP ,/, that/IN the/DT production/NN and/CC extinction/NN of/IN the/DT past/JJ and/CC present/JJ inhabitants/NNS of/IN the/DT world/NN should/MD have/VB been/VBN due/JJ to/TO secondary/JJ causes/NNS ,/, like/IN those/DT determining/VBG the/DT birth/NN and/CC death/NN of/IN the/DT individual/JJ ./. When/WRB I/PRP view/NN all/DT beings/NNS not/RB as/IN special/JJ creations/NNS ,/, but/CC as/IN the/DT lineal/JJ descendants/NNS of/IN some/DT few/JJ beings/NNS which/WDT lived/VBD long/JJ before/IN the/DT first/JJ bed/NN of/IN the/DT Cambrian/NNP system/NN was/VBD deposited/VBN ,/, they/PRP seem/VB to/TO me/PRP to/TO become/VB ennobled/VBN ./. Judging/VBG from/IN the/DT past/JJ ,/, we/PRP may/MD safely/RB infer/VB that/IN not/RB one/CD living/VBG species/NN will/MD transmit/VB its/PRP$ unaltered/JJ likeness/NN to/TO a/DT distant/JJ futurity/NN ./. And/CC of/IN the/DT species/NN now/RB living/VBG very/RB few/JJ will/MD transmit/VB progeny/NN of/IN any/DT kind/NN to/TO a/DT far/RB distant/JJ futurity/NN ;/: for/IN the/DT manner/NN in/IN which/WDT all/DT organic/JJ beings/NNS are/VBP grouped/VBN ,/, shows/VBZ that/IN the/DT greater/JJR number/NN of/IN species/NN in/IN each/DT genus/NN ,/, and/CC all/DT the/DT species/NN in/IN many/JJ genera/NN ,/, have/VBP left/VBN no/DT descendants/NNS ,/, but/CC have/VBP become/VB utterly/RB extinct/JJ ./. We/PRP can/MD so/RB far/RB take/VB a/DT prophetic/JJ glance/NN into/IN futurity/NN as/IN to/TO foretell/VB that/IN it/PRP will/MD be/VB the/DT common/JJ and/CC widely/RB spread/NN species/NN ,/, belonging/VBG to/TO the/DT larger/JJR and/CC dominant/JJ groups/NNS within/IN each/DT class/NN ,/, which/WDT will/MD ultimately/RB prevail/VB and/CC procreate/VB new/JJ and/CC dominant/JJ species/NN ./. As/IN all/DT the/DT living/VBG forms/NNS of/IN life/NN are/VBP the/DT lineal/JJ descendants/NNS of/IN those/DT which/WDT lived/VBD long/JJ before/IN the/DT Cambrian/NNP epoch/NN ,/, we/PRP may/MD feel/VB certain/JJ that/IN the/DT ordinary/JJ succession/NN by/IN generation/NN has/VBZ never/RB once/RB been/VBN broken/VBN ,/, and/CC that/IN no/DT cataclysm/NN has/VBZ desolated/VBN the/DT whole/JJ world/NN ./. Hence/RB we/PRP may/MD look/VB with/IN some/DT confidence/NN to/TO secure/VB future/NN of/IN great/JJ length/NN ./. And/CC as/IN natural/JJ selection/NN works/NNS solely/RB by/IN and/CC for/IN the/DT good/JJ of/IN each/DT being/VBG ,/, all/DT corporeal/JJ and/CC mental/JJ endowments/NNS will/MD tend/VB to/TO progress/NN towards/IN perfection/NN ./. It/PRP is/VBZ interesting/JJ to/TO contemplate/VB a/DT tangled/JJ bank/NN ,/, clothed/VBN with/IN many/JJ plants/NNS of/IN many/JJ kinds/NNS ,/, with/IN birds/NNS singing/VBG on/IN the/DT bushes/NNS ,/, with/IN various/JJ insects/NNS flitting/VBG about/IN ,/, and/CC with/IN worms/NNS crawling/VBG through/IN the/DT damp/VB earth/NN ,/, and/CC to/TO reflect/VB that/IN these/DT elaborately/RB constructed/VBN forms/NNS ,/, so/RB different/JJ from/IN each/DT other/JJ ,/, and/CC dependent/JJ upon/IN each/DT other/JJ in/IN so/RB complex/JJ a/DT manner/NN ,/, have/VBP all/DT been/VBN produced/VBN by/IN laws/NNS acting/VBG around/IN us/PRP ./. These/DT laws/NNS ,/, taken/VBN in/IN the/DT largest/JJS sense/NN ,/, being/VBG Growth/NN with/IN Reproduction/NNP ;/: Inheritance/NN which/WDT is/VBZ almost/RB implied/VBN by/IN reproduction/NN ;/: Variability/NN from/IN the/DT indirect/JJ and/CC direct/JJ action/NN of/IN the/DT conditions/NNS of/IN life/NN and/CC from/IN use/NN and/CC disuse/NN :/: a/DT Ratio/NNP of/IN Increase/VB so/RB high/JJ as/IN to/TO lead/VB to/TO a/DT Struggle/NNP for/IN Life/NNP ,/, and/CC as/IN a/DT consequence/NN to/TO Natural/NNP Selection/NN ,/, entailing/VBG Divergence/NNP of/IN Character/NN and/CC the/DT Extinction/NNP of/IN less/JJR improved/VBN forms/NNS ./. Thus/RB ,/, from/IN the/DT war/NN of/IN nature/NN ,/, from/IN famine/NN and/CC death/NN ,/, the/DT most/RBS exalted/JJ object/NN which/WDT we/PRP are/VBP capable/JJ of/IN conceiving/VBG ,/, namely/RB ,/, the/DT production/NN of/IN the/DT higher/JJR animals/NNS ,/, directly/RB follows/VBZ ./. There/EX is/VBZ grandeur/NN in/IN this/DT view/NN of/IN life/NN ,/, with/IN its/PRP$ several/JJ powers/NNS ,/, having/VBG been/VBN originally/RB breathed/VBD by/IN the/DT Creator/NNP into/IN a/DT few/JJ forms/NNS or/CC into/IN one/CD ;/: and/CC that/IN ,/, whilst/NN this/DT planet/NN has/VBZ gone/VBN cycling/NN on/IN according/VBG to/TO the/DT fixed/VBN law/NN of/IN gravity/NN ,/, from/IN so/RB simple/JJ a/DT beginning/VBG endless/JJ forms/NNS most/RBS beautiful/JJ and/CC most/RBS wonderful/JJ have/VBP been/VBN ,/, and/CC are/VBP being/VBG evolved/VBN ./. THE/DT END/NNP GLOSSARY/NNP GLOSSARY/NNP OF/IN THE/DT PRINCIPAL/NNP SCIENTIFIC/NNP TERMS/NNP USED/VBD IN/IN THE/DT PRESENT/NNP VOLUME/NN I/PRP am/VBP indebted/JJ to/TO the/DT kindness/NN of/IN Mr/NNP ./. W/NNP ./. S/NNP ./. Dallas/NNP for/IN this/DT Glossary/NNP ,/, which/WDT has/VBZ been/VBN given/VBN because/IN several/JJ readers/NNS have/VBP complained/VBD to/TO me/PRP that/IN some/DT of/IN the/DT terms/NNS used/VBN were/VBD unintelligible/JJ to/TO them/PRP ./. Mr/NNP ./. Dallas/NNP has/VBZ endeavoured/VBN to/TO give/VB the/DT explanations/NNS of/IN the/DT terms/NNS in/IN as/IN popular/JJ a/DT form/NN as/IN possible/JJ ./. ABERRANT/NNP ,/, Forms/NNPS or/CC groups/NNS of/IN animals/NNS or/CC plants/NNS which/WDT deviate/VB in/IN important/JJ characters/NNS from/IN their/PRP$ nearest/JJS allies/NNS ,/, so/RB as/IN not/RB to/TO be/VB easily/RB included/VBD in/IN the/DT same/JJ group/NN with/IN them/PRP ,/, are/VBP said/VBD to/TO be/VB aberrant/JJ ./. ABERRATION/NNP (/( in/IN Optics/NNP )/SYM ,/, In/IN the/DT refraction/NN of/IN light/NN by/IN a/DT convex/JJ lens/NN the/DT rays/NNS passing/VBG through/IN different/JJ parts/NNS of/IN the/DT lens/NN are/VBP brought/VBN to/TO a/DT focus/NN at/IN slightly/RB different/JJ distances/NNS ,/, this/DT is/VBZ called/VBN spherical/JJ aberration/NN ;/: at/IN the/DT same/JJ time/NN the/DT coloured/JJ rays/NNS are/VBP separated/VBN by/IN the/DT prismatic/JJ action/NN of/IN the/DT lens/NN and/CC likewise/RB brought/VBN to/TO a/DT focus/NN at/IN different/JJ distances/NNS ,/, this/DT is/VBZ chromatic/JJ aberration/NN ./. ABNORMAL/NNP ,/, Contrary/JJ to/TO the/DT general/JJ rule/NN ./. ABORTED/NNP ,/, An/DT organ/NN is/VBZ said/VBD to/TO be/VB aborted/JJ ,/, when/WRB its/PRP$ development/NN has/VBZ been/VBN arrested/VBN at/IN a/DT very/RB early/JJ stage/NN ./. ALBINISM/NNP ,/, Albinos/NNP are/VBP animals/NNS in/IN which/WDT the/DT usual/JJ colouring/VBG matters/NNS characteristic/JJ of/IN the/DT species/NN have/VBP not/RB been/VBN produced/VBN in/IN the/DT skin/NN and/CC its/PRP$ appendages/NNS ./. Albinism/NNP is/VBZ the/DT state/NN of/IN being/VBG an/DT albino/NN ./. ALGAE/NNP ,/, A/DT class/NN of/IN plants/NNS including/VBG the/DT ordinary/JJ seaweeds/NNS and/CC the/DT filamentous/JJ fresh/JJ water/NN weeds/NNS ./. ALTERNATION/NNP OF/IN GENERATIONS/NNP ,/, This/DT term/NN is/VBZ applied/VBN to/TO a/DT peculiar/JJ mode/NN of/IN reproduction/NN which/WDT prevails/VBZ among/IN many/JJ of/IN the/DT lower/JJR animals/NNS ,/, in/IN which/WDT the/DT egg/NN produces/VBZ a/DT living/VBG form/NN quite/RB different/JJ from/IN its/PRP$ parent/NN ,/, but/CC from/IN which/WDT the/DT parent/NN form/NN is/VBZ reproduced/VBN by/IN a/DT process/NN of/IN budding/VBG ,/, or/CC by/IN the/DT division/NN of/IN the/DT substance/NN of/IN the/DT first/JJ product/NN of/IN the/DT egg/NN ./. AMMONITES/NNP ,/, A/DT group/NN of/IN fossil/JJ ,/, spiral/NN ,/, chambered/VBN shells/NNS ,/, allied/VBN to/TO the/DT existing/VBG pearly/JJ nautilus/JJ ,/, but/CC having/VBG the/DT partitions/NNS between/IN the/DT chambers/NNS waved/VBD in/IN complicated/VBN patterns/NNS at/IN their/PRP$ junction/NN with/IN the/DT outer/JJ wall/NN of/IN the/DT shell/NN ./. ANALOGY/NNP ,/, That/DT resemblance/NN of/IN structures/NNS which/WDT depends/VBZ upon/IN similarity/NN of/IN function/NN ,/, as/IN in/IN the/DT wings/NNS of/IN insects/NNS and/CC birds/NNS ./. Such/JJ structures/NNS are/VBP said/VBD to/TO be/VB analogous/JJ ,/, and/CC to/TO be/VB analogues/NNS of/IN each/DT other/JJ ./. ANIMALCULE/NNP ,/, A/DT minute/NN animal/NN :/: generally/RB applied/VBN to/TO those/DT visible/JJ only/RB by/IN the/DT microscope/NN ./. ANNELIDS/NNP ,/, A/DT class/NN of/IN worms/NNS in/IN which/WDT the/DT surface/NN of/IN the/DT body/NN exhibits/NNS a/DT more/JJR or/CC less/JJR distinct/JJ division/NN into/IN rings/NNS or/CC segments/NNS ,/, generally/RB provided/VBN with/IN appendages/NNS for/IN locomotion/NN and/CC with/IN gills/NNS ./. It/PRP includes/VBZ the/DT ordinary/JJ marine/NN worms/NNS ,/, the/DT earthworms/NNS ,/, and/CC the/DT leeches/NNS ./. ANTENNAE/NNP ,/, Jointed/VBN organs/NNS appended/VBN to/TO the/DT head/NN in/IN insects/NNS ,/, Crustacea/NNP and/CC centipedes/NNS ,/, and/CC not/RB belonging/VBG to/TO the/DT mouth/NN ./. ANTHERS/NNP ,/, The/DT summits/NNS of/IN the/DT stamens/NNS of/IN flowers/NNS ,/, in/IN which/WDT the/DT pollen/NN or/CC fertilising/VBG dust/NN is/VBZ produced/VBN ./. APLACENTALIA/NNP ,/, APLACENTATA/NNP or/CC Aplacental/NNP Mammals/NNP ./. See/VB MAMMALIA/NNP ./. ARCHETYPAL/NNP ,/, Of/IN or/CC belonging/VBG to/TO the/DT Archetype/NNP ,/, or/CC ideal/JJ primitive/JJ form/NN upon/IN which/WDT all/DT the/DT beings/NNS of/IN a/DT group/NN seem/VB to/TO be/VB organised/VBD ./. ARTICULATA/NNP ,/, A/DT great/JJ division/NN of/IN the/DT animal/NN kingdom/NN characterised/VBN generally/RB by/IN having/VBG the/DT surface/NN of/IN the/DT body/NN divided/VBN into/IN rings/NNS called/VBN segments/NNS ,/, a/DT greater/JJR or/CC less/JJR number/NN of/IN which/WDT are/VBP furnished/VBN with/IN jointed/VBN legs/NNS (/( such/JJ as/IN insects/NNS ,/, crustaceans/NNS and/CC centipedes/NNS )/SYM ./. ASYMMETRICAL/NNP ,/, Having/VBG the/DT two/CD sides/NNS unlike/IN ./. ATROPHIED/NNP ,/, Arrested/VBN in/IN development/NN at/IN a/DT very/RB early/JJ age/NN ./. BALANUS/NNP ,/, The/DT genus/NN including/VBG the/DT common/JJ acorn/RB shells/NNS which/WDT live/VB in/IN abundance/NN on/IN the/DT rocks/NNS of/IN the/DT sea/NN coast/NN ./. BATRACRIANS/NNP ,/, A/DT class/NN of/IN animals/NNS allied/VBN to/TO the/DT reptiles/NNS ,/, but/CC undergoing/VBG a/DT peculiar/JJ metamorphosis/NN ,/, in/IN which/WDT the/DT young/JJ animal/NN is/VBZ generally/RB aquatic/JJ and/CC breathes/VBZ by/IN gills/NNS ./. (/( Examples/NNS ,/, frogs/NNS ,/, toads/NNS ,/, and/CC newts/NNS ./. )/SYM BOULDERS/NNP ,/, Large/JJ transported/VBN blocks/NNS of/IN stone/NN generally/RB imbedded/VBN in/IN clays/NNS or/CC gravel/NN ./. BRACHIOPODA/NNP ,/, A/DT class/NN of/IN marine/NN Mollusca/NNP ,/, or/CC softbodied/VBN animals/NNS ,/, furnished/VBN with/IN a/DT bivalve/NN shell/NN ,/, attached/VBN to/TO submarine/NN objects/NNS by/IN a/DT stalk/VBP which/WDT passes/VBZ through/IN an/DT aperture/NN in/IN one/CD of/IN the/DT valves/NNS ,/, and/CC furnished/VBN with/IN fringed/VBN arms/NNS ,/, by/IN the/DT action/NN of/IN which/WDT food/NN is/VBZ carried/VBN to/TO the/DT mouth/NN ./. BRANCHIAE/NNP ,/, Gills/NNP or/CC organs/NNS for/IN respiration/NN in/IN water/NN ./. BRANCHIAL/NNP ,/, Pertaining/VBG to/TO gills/NNS or/CC branchiae/NN ./. CAMBRIAN/NNP SYSTEM/NNP ,/, A/DT series/NN of/IN very/RB ancient/JJ Palaeozoic/NNP rocks/NNS ,/, between/IN the/DT Laurentian/NNP and/CC the/DT Silurian/NNP ./. Until/IN recently/RB these/DT were/VBD regarded/VBN as/IN the/DT oldest/JJS fossiliferous/JJ rocks/NNS ./. CANIDAE/NNP ,/, The/DT dog/NN family/NN ,/, including/VBG the/DT dog/NN ,/, wolf/NN ,/, fox/NN ,/, jackal/JJ ,/, &c/NN ./. CARAPACE/NNP ,/, The/DT shell/NN enveloping/VBG the/DT anterior/JJ part/NN of/IN the/DT body/NN in/IN crustaceans/NNS generally/RB ;/: applied/VBN also/RB to/TO the/DT hard/JJ shelly/RB pieces/NNS of/IN the/DT cirripedes/NNS ./. CARBONIFEROUS/NNP ,/, This/DT term/NN is/VBZ applied/VBN to/TO the/DT great/JJ formation/NN which/WDT includes/VBZ among/IN other/JJ rocks/NNS ,/, the/DT coal/NN measures/NNS ./. It/PRP belongs/VBZ to/TO the/DT oldest/JJS ,/, or/CC Palaeozoic/NNP ,/, system/NN of/IN formations/NNS ./. CAUDAL/NNP ,/, Of/IN or/CC belonging/VBG to/TO the/DT tail/NN ./. CEPHALOPODS/NNP ,/, The/DT highest/JJS class/NN of/IN the/DT Molluscs/NNP or/CC soft/JJ bodied/JJ animals/NNS ,/, characterised/VBN by/IN having/VBG the/DT mouth/NN surrounded/VBN by/IN a/DT greater/JJR or/CC less/JJR number/NN of/IN fleshy/JJ arms/NNS or/CC tentacles/NNS ,/, which/WDT ,/, in/IN most/RBS living/VBG species/NN ,/, are/VBP furnished/VBN with/IN sucking/VBG cups/NNS ./. (/( Examples/NNS ,/, cuttle/NN fish/NN ,/, nautilus/JJ ./. )/SYM CETACEA/NNP ,/, An/DT order/NN of/IN Mammalia/NNP ,/, including/VBG the/DT whales/NNS ,/, dolphins/NNS ,/, &c/NN ./. ,/, having/VBG the/DT form/NN of/IN the/DT body/NN fish/NN like/IN ,/, the/DT skin/NN naked/JJ ,/, and/CC only/RB the/DT forelimbs/NNS developed/VBN ./. CHELONIA/NNP ,/, An/DT order/NN of/IN reptiles/NNS including/VBG the/DT turtles/NNS ,/, tortoises/NNS ,/, &c/NN ./. CIRRIPEDES/NNP ,/, An/DT order/NN of/IN crustaceans/NNS including/VBG the/DT barnacles/NNS and/CC acorn/RB shells/NNS ./. Their/PRP$ young/JJ resemble/VB those/DT of/IN many/JJ other/JJ crustaceans/NNS in/IN form/NN ;/: but/CC when/WRB mature/JJ they/PRP are/VBP always/RB attached/VBN to/TO other/JJ objects/NNS ,/, either/DT directly/RB or/CC by/IN means/VBZ of/IN a/DT stalk/VBP ,/, and/CC their/PRP$ bodies/NNS are/VBP enclosed/VBN by/IN a/DT calcareous/JJ shell/NN composed/VBN of/IN several/JJ pieces/NNS ,/, two/CD of/IN which/WDT can/MD open/JJ to/TO give/VB issue/NN to/TO a/DT bunch/NN of/IN curled/VBD ,/, jointed/VBN tentacles/NNS ,/, which/WDT represent/VB the/DT limbs/NNS ./. COCCUS/NNP ,/, The/DT genus/NN of/IN insects/NNS including/VBG the/DT cochineal/JJ ./. In/IN these/DT the/DT male/JJ is/VBZ a/DT minute/NN ,/, winged/VBD fly/VB ,/, and/CC the/DT female/JJ generally/RB a/DT motionless/JJ ,/, berry/NN like/IN mass/NN ./. COCOON/NNP ,/, A/DT case/NN usually/RB of/IN silky/JJ material/NN ,/, in/IN which/WDT insects/NNS are/VBP frequently/RB enveloped/VBN during/IN the/DT second/JJ or/CC resting/VBG stage/NN (/( pupa/NN )/SYM of/IN their/PRP$ existence/NN ./. The/DT term/NN "/" cocoon/NN stage/NN "/" is/VBZ here/RB used/VBN as/IN equivalent/NN to/TO "/" pupa/NN stage/NN ./. "/" COELOSPERMOUS/NNP ,/, A/DT term/NN applied/VBN to/TO those/DT fruits/NNS of/IN the/DT Umbelliferae/NNP which/WDT have/VBP the/DT seed/NN hollowed/VBD on/IN the/DT inner/JJ face/NN ./. COLEOPTERA/NNP beetles/NNS ,/, an/DT order/NN of/IN insects/NNS ,/, having/VBG a/DT biting/VBG mouth/NN and/CC the/DT first/JJ pair/NN of/IN wings/NNS more/JJR or/CC less/JJR horny/JJ ,/, forming/VBG sheaths/NNS for/IN the/DT second/JJ pair/NN ,/, and/CC usually/RB meeting/NN in/IN a/DT straight/JJ line/NN down/RB the/DT middle/NN of/IN the/DT back/RB ./. COLUMN/NNP ,/, A/DT peculiar/JJ organ/NN in/IN the/DT flowers/NNS of/IN orchids/NNS ,/, in/IN which/WDT the/DT stamens/NNS ,/, style/NN and/CC stigma/NN (/( or/CC the/DT reproductive/JJ parts/NNS )/SYM are/VBP united/VBN ./. COMPOSITAE/NNP ,/, or/CC COMPOSITOUS/NNP PLANTS/NNS ,/, Plants/NNS in/IN which/WDT the/DT inflorescence/NN consists/VBZ of/IN numerous/JJ small/JJ flowers/NNS (/( florets/NNS )/SYM brought/VBN together/RB into/IN a/DT dense/JJ head/NN ,/, the/DT base/NN of/IN which/WDT is/VBZ enclosed/VBN by/IN a/DT common/JJ envelope/NN ./. (/( Examples/NNS ,/, the/DT daisy/NN ,/, dandelion/NN ,/, &c/NN ./. )/SYM CONFERVAE/NNP ,/, The/DT filamentous/JJ weeds/NNS of/IN fresh/JJ water/NN ./. CONGLOMERATE/NNP ,/, A/DT rock/NN made/VBN up/IN of/IN fragments/NNS of/IN rock/NN or/CC pebbles/NNS ,/, cemented/VBN together/RB by/IN some/DT other/JJ material/NN ./. COROLLA/NNP The/DT second/JJ envelope/NN of/IN a/DT flower/NN usually/RB composed/VBN of/IN coloured/JJ ,/, leaf/NN like/IN organs/NNS (/( petals/NNS )/SYM ,/, which/WDT may/MD be/VB united/VBN by/IN their/PRP$ edges/NNS either/DT in/IN the/DT basal/NN part/NN or/CC throughout/IN ./. CORRELATION/NNP ,/, The/DT normal/JJ coincidence/NN of/IN one/CD phenomenon/NN ,/, character/NN ,/, &c/NN ./. ,/, with/IN another/DT ./. CORYMB/NNP ,/, A/DT bunch/NN of/IN flowers/NNS in/IN which/WDT those/DT springing/VBG from/IN the/DT lower/JJR part/NN of/IN the/DT flower/NN stalk/VBP are/VBP supported/VBN on/IN long/JJ stalks/NNS so/RB as/IN to/TO be/VB nearly/RB on/IN a/DT level/NN with/IN the/DT upper/JJ ones/NNS ./. COTYLEDONS/NNP ,/, The/DT first/JJ or/CC seed/NN leaves/VBZ of/IN plants/NNS ./. CRUSTACEANS/NNP ,/, A/DT class/NN of/IN articulated/VBN animals/NNS ,/, having/VBG the/DT skin/NN of/IN the/DT body/NN generally/RB more/JJR or/CC less/JJR hardened/VBN by/IN the/DT deposition/NN of/IN calcareous/JJ matter/NN ,/, breathing/NN by/IN means/VBZ of/IN gills/NNS ./. (/( examples/NNS ,/, crab/NN ,/, lobster/NN ,/, shrimp/NN ,/, &c/NN ./. )/SYM CURCULIO/NNP ,/, The/DT old/JJ generic/JJ term/NN for/IN the/DT beetles/NNS known/VBN as/IN weevils/NNS ,/, characterised/VBN by/IN their/PRP$ four/CD jointed/VBN feet/NNS ,/, and/CC by/IN the/DT head/NN being/VBG produced/VBN into/IN a/DT sort/NN of/IN beak/NN ,/, upon/IN the/DT sides/NNS of/IN which/WDT the/DT antennae/NNS are/VBP inserted/VBN ./. CUTANEOUS/NNP ,/, Of/IN or/CC belonging/VBG to/TO the/DT skin/NN ./. DEGRADATION/NNP ,/, The/DT wearing/VBG down/RB of/IN land/NN by/IN the/DT action/NN of/IN the/DT sea/NN or/CC of/IN meteoric/JJ agencies/NNS ./. DENUDATION/NNP ,/, The/DT wearing/VBG away/RB of/IN the/DT surface/NN of/IN the/DT land/NN by/IN water/NN ./. DEVONIAN/NNP SYSTEM/NNP or/CC formation/NN ,/, A/DT series/NN of/IN Palaeozoic/NNP rocks/NNS ,/, including/VBG the/DT Old/NNP Red/NNP Sandstone/NNP ./. DICOTYLEDONS/NNP ,/, or/CC DICOTYLEDONOUS/NNP PLANTS/NNS ,/, A/DT class/NN of/IN plants/NNS characterised/VBN by/IN having/VBG two/CD seed/NN leaves/VBZ ,/, by/IN the/DT formation/NN of/IN new/JJ wood/NN between/IN the/DT bark/NN and/CC the/DT old/JJ wood/NN (/( exogenous/JJ growth/NN )/SYM and/CC by/IN the/DT reticulation/NN of/IN the/DT veins/NNS of/IN the/DT leaves/VBZ ./. The/DT parts/NNS of/IN the/DT flowers/NNS are/VBP generally/RB in/IN multiples/NNS of/IN five/CD ./. DIFFERENTATION/NNP ,/, The/DT separation/NN or/CC discrimination/NN of/IN parts/NNS or/CC organs/NNS which/WDT in/IN simpler/JJR forms/NNS of/IN life/NN are/VBP more/JJR or/CC less/JJR united/VBN ./. DIMORPHIC/NNP ,/, Having/VBG two/CD distinct/JJ forms/NNS ./. Dimorphism/NNP is/VBZ the/DT condition/NN of/IN the/DT appearance/NN of/IN the/DT same/JJ species/NN under/IN two/CD dissimilar/JJ forms/NNS ./. DIOECIOUS/NNP ,/, Having/VBG the/DT organs/NNS of/IN the/DT sexes/NNS upon/IN distinct/JJ individuals/NNS ./. DIORITE/NNP ,/, A/DT peculiar/JJ form/NN of/IN greenstone/NN ./. DORSAL/NNP ,/, Of/IN or/CC belonging/VBG to/TO the/DT back/RB ./. EDENTATA/NNP ,/, A/DT peculiar/JJ order/NN of/IN quadrupeds/NNS ,/, characterised/VBN by/IN the/DT absence/NN of/IN at/IN least/JJS the/DT middle/NN incisor/NN (/( front/NN )/SYM teeth/NNS in/IN both/DT jaws/NNS ./. (/( Examples/NNS ,/, the/DT sloths/NNS and/CC armadillos/NNS ./. )/SYM ELYTRA/NNP ,/, The/DT hardened/VBN fore/NN wings/NNS of/IN beetles/NNS ,/, serving/VBG as/IN sheaths/NNS for/IN the/DT membranous/JJ hind/JJ wings/NNS ,/, which/WDT constitute/VBP the/DT true/JJ organs/NNS of/IN flight/NN ./. EMBRYO/NNP ,/, The/DT young/JJ animal/NN undergoing/VBG development/NN within/IN the/DT egg/NN or/CC womb/NN ./. EMBRYOLOGY/NNP ,/, The/DT study/NN of/IN the/DT development/NN of/IN the/DT embryo/NN ./. ENDEMIC/NNP ,/, Peculiar/NNP to/TO a/DT given/VBN locality/NN ./. ENTOMOSTRACA/NNP ,/, A/DT division/NN of/IN the/DT class/NN Crustacea/NNP ,/, having/VBG all/DT the/DT segments/NNS of/IN the/DT body/NN usually/RB distinct/JJ ,/, gills/NNS attached/VBN to/TO the/DT feet/NNS or/CC organs/NNS of/IN the/DT mouth/NN ,/, and/CC the/DT feet/NNS fringed/VBN with/IN fine/JJ hairs/NNS ./. They/PRP are/VBP generally/RB of/IN small/JJ size/NN ./. EOCENE/NNP ,/, The/DT earliest/JJS of/IN the/DT three/CD divisions/NNS of/IN the/DT Tertiary/NNP epoch/NN of/IN geologists/NNS ./. Rocks/NNP of/IN this/DT age/NN contain/VB a/DT small/JJ proportion/NN of/IN shells/NNS identical/JJ with/IN species/NN now/RB living/VBG ./. EPHEMEROUS/NNP INSECTS/NNP ,/, Insects/NNS allied/VBN to/TO the/DT May/NNP fly/VB ./. FAUNA/NNP ,/, The/DT totality/NN of/IN the/DT animals/NNS naturally/RB inhabiting/VBG a/DT certain/JJ country/NN or/CC region/NN ,/, or/CC which/WDT have/VBP lived/VBD during/IN a/DT given/VBN geological/JJ period/NN ./. FELIDAE/NNP ,/, The/DT cat/NN family/NN ./. FERAL/NNP ,/, Having/VBG become/VB wild/JJ from/IN a/DT state/NN of/IN cultivation/NN or/CC domestication/NN ./. FLORA/NNP ,/, The/DT totality/NN of/IN the/DT plants/NNS growing/VBG naturally/RB in/IN a/DT country/NN ,/, or/CC during/IN a/DT given/VBN geological/JJ period/NN ./. FLORETS/NNP ,/, Flowers/NNPS imperfectly/RB developed/VBN in/IN some/DT respects/NNS ,/, and/CC collected/VBN into/IN a/DT dense/JJ spike/NN or/CC head/NN ,/, as/IN in/IN the/DT grasses/NNS ,/, the/DT dandelion/NN ,/, &c/NN ./. FOETAL/NNP ,/, Of/IN or/CC belonging/VBG to/TO the/DT foetus/JJ ,/, or/CC embryo/NN in/IN course/NN of/IN development/NN ./. FORAMINIFERA/NNP ,/, A/DT class/NN of/IN animals/NNS of/IN very/RB low/JJ organisation/NN ,/, and/CC generally/RB of/IN small/JJ size/NN ,/, having/VBG a/DT jellylike/JJ body/NN ,/, from/IN the/DT surface/NN of/IN which/WDT delicate/JJ filaments/NNS can/MD be/VB given/VBN off/IN and/CC retracted/VBN for/IN the/DT prehension/NN of/IN external/JJ objects/NNS ,/, and/CC having/VBG a/DT calcareous/JJ or/CC sandy/JJ shell/NN ,/, usually/RB divided/VBN into/IN chambers/NNS ,/, and/CC perforated/JJ with/IN small/JJ apertures/NNS ./. FOSSILIFEROUS/NNP ,/, Containing/VBG fossils/NNS ./. FOSSORIAL/NNP ,/, Having/VBG a/DT faculty/NN of/IN digging/VBG ./. The/DT Fossorial/NNP Hymenoptera/NNP are/VBP a/DT group/NN of/IN wasp/NN like/IN insects/NNS ,/, which/WDT burrow/NN in/IN sandy/JJ soil/NN to/TO make/VB nests/NNS for/IN their/PRP$ young/JJ ./. FRENUM/NNP (/( pl/NN ./. FRENA/NNP )/SYM ,/, A/DT small/JJ band/NN or/CC fold/VB of/IN skin/NN ./. FUNGI/NNP (/( sing/VB ./. FUNGUS/NNP )/SYM ,/, A/DT class/NN of/IN cellular/JJ plants/NNS ,/, of/IN which/WDT mushrooms/NNS ,/, toadstools/NNS ,/, and/CC moulds/NNS ,/, are/VBP familiar/JJ examples/NNS ./. FURCULA/NNP ,/, The/DT forked/JJ bone/NN formed/VBN by/IN the/DT union/NN of/IN the/DT collar/NN bones/NNS in/IN many/JJ birds/NNS ,/, such/JJ as/IN the/DT common/JJ fowl/NN ./. GALLINACEOUS/NNP BIRDS/NNS ,/, An/DT order/NN of/IN birds/NNS of/IN which/WDT the/DT common/JJ fowl/NN ,/, turkey/NN ,/, and/CC pheasant/NN ,/, are/VBP well/RB known/VBN examples/NNS ./. GALLUS/NNP ,/, The/DT genus/NN of/IN birds/NNS which/WDT includes/VBZ the/DT common/JJ fowl/NN ./. GANGLION/NNP ,/, A/DT swelling/VBG or/CC knot/NN from/IN which/WDT nerves/NNS are/VBP given/VBN off/IN as/IN from/IN a/DT centre/NN ./. GANOID/NNP FISHES/NNP ,/, Fishes/NNP covered/VBN with/IN peculiar/JJ enamelled/JJ bony/JJ scales/NNS ./. Most/JJS of/IN them/PRP are/VBP extinct/JJ ./. GERMINAL/NNP VESICLE/NNP ,/, A/DT minute/NN vesicle/NN in/IN the/DT eggs/NNS of/IN animals/NNS ,/, from/IN which/WDT development/NN of/IN the/DT embryo/NN proceeds/NNS ./. GLACIAL/NNP PERIOD/NN ,/, A/DT period/NN of/IN great/JJ cold/JJ and/CC of/IN enormous/JJ extension/NN of/IN ice/NN upon/IN the/DT surface/NN of/IN the/DT earth/NN ./. It/PRP is/VBZ believed/VBN that/IN glacial/JJ periods/NNS have/VBP occurred/VBD repeatedly/RB during/IN the/DT geological/JJ history/NN of/IN the/DT earth/NN ,/, but/CC the/DT term/NN is/VBZ generally/RB applied/VBN to/TO the/DT close/VB of/IN the/DT Tertiary/NNP epoch/NN ,/, when/WRB nearly/RB the/DT whole/JJ of/IN Europe/NNP was/VBD subjected/VBN to/TO an/DT arctic/JJ climate/NN ./. GLAND/NNP ,/, An/DT organ/NN which/WDT secretes/NNS or/CC separates/VBZ some/DT peculiar/JJ product/NN from/IN the/DT blood/NN or/CC sap/VB of/IN animals/NNS or/CC plants/NNS ./. GLOTTIS/NNP ,/, The/DT opening/NN of/IN the/DT windpipe/NN into/IN the/DT oesophagus/JJ or/CC gullet/NN ./. GNEISS/NNP ,/, A/DT rock/NN approaching/VBG granite/NN in/IN composition/NN ,/, but/CC more/JJR or/CC less/JJR laminated/VBN ,/, and/CC really/RB produced/VBN by/IN the/DT alteration/NN of/IN a/DT sedimentary/JJ deposit/NN after/IN its/PRP$ consolidation/NN ./. GRALLATORES/NNP ,/, The/DT so/RB called/VBN wading/VBG birds/NNS (/( storks/NNS ,/, cranes/NNS ,/, snipes/VBZ ,/, &c/NN ./. )/SYM ,/, which/WDT are/VBP generally/RB furnished/VBN with/IN long/JJ legs/NNS ,/, bare/JJ of/IN feathers/NNS above/IN the/DT heel/NN ,/, and/CC have/VBP no/DT membranes/NNS between/IN the/DT toes/NNS ./. GRANITE/NNP ,/, A/DT rock/NN consisting/VBG essentially/RB of/IN crystals/NNS of/IN felspar/NN and/CC mica/NN in/IN a/DT mass/NN of/IN quartz/NN ./. HABITAT/NNP ,/, The/DT locality/NN in/IN which/WDT a/DT plant/NN or/CC animal/NN naturally/RB lives/NNS ./. HEMIPTERA/NNP ,/, An/DT order/NN or/CC sub/NN order/NN of/IN insects/NNS ,/, characterised/VBN by/IN the/DT possession/NN of/IN a/DT jointed/VBN beak/NN or/CC rostrum/NN ,/, and/CC by/IN having/VBG the/DT fore/NN wings/NNS horny/JJ in/IN the/DT basal/NN portion/NN and/CC membranous/JJ at/IN the/DT extremity/NN ,/, where/WRB they/PRP cross/VB each/DT other/JJ ./. This/DT group/NN includes/VBZ the/DT various/JJ species/NN of/IN bugs/NNS ./. HERMAPHRODITE/NNP ,/, Possessing/VBG the/DT organs/NNS of/IN both/DT sexes/NNS ./. HOMOLOGY/NNP ,/, That/DT relation/NN between/IN parts/NNS which/WDT results/NNS from/IN their/PRP$ development/NN from/IN corresponding/JJ embryonic/JJ parts/NNS ,/, either/DT in/IN different/JJ animals/NNS ,/, as/IN in/IN the/DT case/NN of/IN the/DT arm/NN of/IN man/NN ,/, the/DT fore/NN leg/NN of/IN a/DT quadruped/VBD ,/, and/CC the/DT wing/NN of/IN a/DT bird/NN ;/: or/CC in/IN the/DT same/JJ individual/JJ ,/, as/IN in/IN the/DT case/NN of/IN the/DT fore/NN and/CC hind/JJ legs/NNS in/IN quadrupeds/NNS ,/, and/CC the/DT segments/NNS or/CC rings/NNS and/CC their/PRP$ appendages/NNS of/IN which/WDT the/DT body/NN of/IN a/DT worm/NN ,/, a/DT centipede/NN ,/, &c/NN ./. ,/, is/VBZ composed/VBN ./. The/DT latter/NN is/VBZ called/VBN serial/JJ homology/NN ./. The/DT parts/NNS which/WDT stand/VB in/IN such/JJ a/DT relation/NN to/TO each/DT other/JJ are/VBP said/VBD to/TO be/VB homologous/RB ,/, and/CC one/CD such/JJ part/NN or/CC organ/NN is/VBZ called/VBN the/DT homologue/NN of/IN the/DT other/JJ ./. In/IN different/JJ plants/NNS the/DT parts/NNS of/IN the/DT flower/NN are/VBP homologous/RB ,/, and/CC in/IN general/JJ these/DT parts/NNS are/VBP regarded/VBN as/IN homologous/RB with/IN leaves/VBZ ./. HOMOPTERA/NNP ,/, An/DT order/NN or/CC sub/NN order/NN of/IN insects/NNS having/VBG (/( like/IN the/DT Hemiptera/NNP )/SYM a/DT jointed/VBN beak/NN ,/, but/CC in/IN which/WDT the/DT fore/NN wings/NNS are/VBP either/DT wholly/RB membranous/JJ or/CC wholly/RB leathery/JJ ,/, The/DT Cicadae/NNP ,/, frog/NN hoppers/NNS ,/, and/CC Aphides/NNP ,/, are/VBP well/RB known/VBN examples/NNS ./. HYBRID/NNP ,/, The/DT offspring/NN of/IN the/DT union/NN of/IN two/CD distinct/JJ species/NN ./. HYMENOPTERA/NNP ,/, An/DT order/NN of/IN insects/NNS possessing/VBG biting/VBG jaws/NNS and/CC usually/RB four/CD membranous/JJ wings/NNS in/IN which/WDT there/EX are/VBP a/DT few/JJ veins/NNS ./. Bees/NNP and/CC wasps/NNS are/VBP familiar/JJ examples/NNS of/IN this/DT group/NN ./. HYPERTROPHIED/NNP ,/, Excessively/RB developed/VBN ./. ICHNEUMONIDAE/NNP ,/, A/DT family/NN of/IN hymenopterous/JJ insects/NNS ,/, the/DT members/NNS of/IN which/WDT lay/VBD their/PRP$ eggs/NNS in/IN the/DT bodies/NNS or/CC eggs/NNS of/IN other/JJ insects/NNS ./. IMAGO/NNP ,/, The/DT perfect/JJ (/( generally/RB winged/VBD )/SYM reproductive/JJ state/NN of/IN an/DT insect/NN ./. INDIGENES/NNP ,/, The/DT aboriginal/JJ animal/NN or/CC vegetable/NN inhabitants/NNS of/IN a/DT country/NN or/CC region/NN ./. INFLORESCENCE/NNP ,/, The/DT mode/NN of/IN arrangement/NN of/IN the/DT flowers/NNS of/IN plants/NNS ./. INFUSORIA/NNP ,/, A/DT class/NN of/IN microscopic/JJ animalcules/NNS ,/, so/RB called/VBN from/IN their/PRP$ having/VBG originally/RB been/VBN observed/VBN in/IN infusions/NNS of/IN vegetable/NN matters/NNS ./. They/PRP consist/VB of/IN a/DT gelatinous/JJ material/NN enclosed/VBN in/IN a/DT delicate/JJ membrane/NN ,/, the/DT whole/JJ or/CC part/NN of/IN which/WDT is/VBZ furnished/VBN with/IN short/JJ vibrating/VBG hairs/NNS (/( called/VBN cilia/NNS )/SYM ,/, by/IN means/VBZ of/IN which/WDT the/DT animalcules/NNS swim/VB through/IN the/DT water/NN or/CC convey/VB the/DT minute/NN particles/NNS of/IN their/PRP$ food/NN to/TO the/DT orifice/NN of/IN the/DT mouth/NN ./. INSECTIVOROUS/NNP ,/, Feeding/NNP on/IN insects/NNS ./. INVERTEBRATA/NNP ,/, or/CC INVERTEBRATE/NNP ANIMALS/NNP ,/, Those/DT animals/NNS which/WDT do/VBP not/RB possess/VBP a/DT backbone/NN or/CC spinal/JJ column/NN ./. LACUNAE/NNP ,/, Spaces/NNPS left/VBN among/IN the/DT tissues/NNS in/IN some/DT of/IN the/DT lower/JJR animals/NNS and/CC serving/VBG in/IN place/NN of/IN vessels/NNS for/IN the/DT circulation/NN of/IN the/DT fluids/NNS of/IN the/DT body/NN ./. LAMELLATED/NNP ,/, Furnished/VBN with/IN lamellae/NN or/CC little/JJ plates/NNS ./. LARVA/NNP (/( pl/NN ./. LARVAE/NNP )/SYM ,/, The/DT first/JJ condition/NN of/IN an/DT insect/NN at/IN its/PRP$ issuing/VBG from/IN the/DT egg/NN ,/, when/WRB it/PRP is/VBZ usually/RB in/IN the/DT form/NN of/IN a/DT grub/NN ,/, caterpillar/NN ,/, or/CC maggot/NN ./. LARYNX/NNP ,/, The/DT upper/JJ part/NN of/IN the/DT windpipe/NN opening/NN into/IN the/DT gullet/NN ./. LAURENTIAN/NNP ,/, A/DT group/NN of/IN greatly/RB altered/VBN and/CC very/RB ancient/JJ rocks/NNS ,/, which/WDT is/VBZ greatly/RB developed/VBN along/IN the/DT course/NN of/IN the/DT St/NNP ./. Laurence/NNP ,/, whence/WRB the/DT name/NN ./. It/PRP is/VBZ in/IN these/DT that/IN the/DT earliest/JJS known/VBN traces/NNS of/IN organic/JJ bodies/NNS have/VBP been/VBN found/VBD ./. LEGUMINOSAE/NNP ,/, An/DT order/NN of/IN plants/NNS represented/VBN by/IN the/DT common/JJ peas/NNS and/CC beans/NNS ,/, having/VBG an/DT irregular/JJ flower/NN in/IN which/WDT one/CD petal/JJ stands/VBZ up/IN like/IN a/DT wing/NN ,/, and/CC the/DT stamens/NNS and/CC pistil/NN are/VBP enclosed/VBN in/IN a/DT sheath/NN formed/VBN by/IN two/CD other/JJ petals/NNS ./. The/DT fruit/NN is/VBZ a/DT pod/NN (/( or/CC legume/NN )/SYM ./. LEMURIDAE/NNP ,/, A/DT group/NN of/IN four/CD handed/VBD animals/NNS ,/, distinct/JJ from/IN the/DT monkeys/NNS and/CC approaching/VBG the/DT insectivorous/JJ quadrupeds/NNS in/IN some/DT of/IN their/PRP$ characters/NNS and/CC habits/NNS ./. Its/PRP$ members/NNS have/VBP the/DT nostrils/NNS curved/JJ or/CC twisted/VBN ,/, and/CC a/DT claw/NN instead/RB of/IN a/DT nail/NN upon/IN the/DT first/JJ finger/NN of/IN the/DT hind/JJ hands/NNS ./. LEPIDOPTERA/NNP ,/, An/DT order/NN of/IN insects/NNS ,/, characterised/VBN by/IN the/DT possession/NN of/IN a/DT spiral/NN proboscis/NN ,/, and/CC of/IN four/CD large/JJ more/JJR or/CC less/JJR scaly/RB wings/NNS ./. It/PRP includes/VBZ the/DT well/RB known/VBN butterflies/NNS and/CC moths/NNS ./. LITTORAL/NNP ,/, Inhabiting/VBG the/DT seashore/NN ./. LOESS/NNP ,/, A/DT marly/RB deposit/NN of/IN recent/JJ (/( Post/NNP Tertiary/NNP )/SYM date/NN ,/, which/WDT occupies/VBZ a/DT great/JJ part/NN of/IN the/DT valley/NN of/IN the/DT Rhine/NNP ./. MALACOSTRACA/NNP ,/, The/DT higher/JJR division/NN of/IN the/DT Crustacea/NNP ,/, including/VBG the/DT ordinary/JJ crabs/NNS ,/, lobsters/NNS ,/, shrimps/NNS ,/, &c/NN ./. ,/, together/RB with/IN the/DT woodlice/NN and/CC sand/NN hoppers/NNS ./. MAMMALIA/NNP ,/, The/DT highest/JJS class/NN of/IN animals/NNS ,/, including/VBG the/DT ordinary/JJ hairy/JJ quadrupeds/NNS ,/, the/DT whales/NNS and/CC man/NN ,/, and/CC characterised/VBN by/IN the/DT production/NN of/IN living/VBG young/JJ which/WDT are/VBP nourished/VBN after/IN birth/NN by/IN milk/NN from/IN the/DT teats/NNS (/( Mammae/NNP ,/, Mammary/NNP glands/NNS )/SYM of/IN the/DT mother/NN ./. A/DT striking/JJ difference/NN in/IN embryonic/JJ development/NN has/VBZ led/VBN to/TO the/DT division/NN of/IN this/DT class/NN into/IN two/CD great/JJ groups/NNS ;/: in/IN one/CD of/IN these/DT ,/, when/WRB the/DT embryo/NN has/VBZ attained/VBN a/DT certain/JJ stage/NN ,/, a/DT vascular/JJ connection/NN ,/, called/VBN the/DT placenta/NN ,/, is/VBZ formed/VBN between/IN the/DT embryo/NN and/CC the/DT mother/NN ;/: in/IN the/DT other/JJ this/DT is/VBZ wanting/VBG ,/, and/CC the/DT young/JJ are/VBP produced/VBN in/IN a/DT very/RB incomplete/JJ state/NN ./. The/DT former/JJ ,/, including/VBG the/DT greater/JJR part/NN of/IN the/DT class/NN ,/, are/VBP called/VBN Placental/NNP mammals/NNS ;/: the/DT latter/NN ,/, or/CC Aplacental/NNP mammals/NNS ,/, include/VBP the/DT marsupials/NNS and/CC monotremes/NNS (/( Ornithorhynchus/NNP )/SYM ./. MAMMIFEROUS/NNP ,/, Having/VBG mammae/NN or/CC teats/NNS (/( see/VB MAMMALIA/NNP )/SYM MANDIBLES/NNP ,/, in/IN insects/NNS ,/, the/DT first/JJ or/CC uppermost/JJS pair/NN of/IN jaws/NNS ,/, which/WDT are/VBP generally/RB solid/JJ ,/, horny/JJ ,/, biting/VBG organs/NNS ./. In/IN birds/NNS the/DT term/NN is/VBZ applied/VBN to/TO both/DT jaws/NNS with/IN their/PRP$ horny/JJ coverings/NNS ./. In/IN quadrupeds/NNS the/DT mandible/JJ is/VBZ properly/RB the/DT lower/JJR jaw/NN ./. MARSUPIALS/NNP ,/, An/DT order/NN of/IN Mammalia/NNP in/IN which/WDT the/DT young/JJ are/VBP born/VBN in/IN a/DT very/RB incomplete/JJ state/NN of/IN development/NN ,/, and/CC carried/VBD by/IN the/DT mother/NN ,/, while/IN sucking/VBG ,/, in/IN a/DT ventral/JJ pouch/NN (/( marsupium/NN )/SYM ,/, such/JJ as/IN the/DT kangaroos/NNS ,/, opossums/NNS ,/, &c/NN ./. (/( see/VB MAMMALIA/NNP )/SYM ./. MAXILLAE/NNP ,/, in/IN insects/NNS ,/, the/DT second/JJ or/CC lower/JJR pair/NN of/IN jaws/NNS ,/, which/WDT are/VBP composed/VBN of/IN several/JJ joints/NNS and/CC furnished/VBN with/IN peculiar/JJ jointed/VBN appendages/NNS called/VBN palpi/NN ,/, or/CC feelers/NNS ./. MELANISM/NNP ,/, The/DT opposite/JJ of/IN albinism/NN ;/: an/DT undue/JJ development/NN of/IN colouring/VBG material/NN in/IN the/DT skin/NN and/CC its/PRP$ appendages/NNS ./. METAMORPHIC/NNP ROCKS/NNP ,/, Sedimentary/NNP rocks/NNS which/WDT have/VBP undergone/VBN alteration/NN ,/, generally/RB by/IN the/DT action/NN of/IN heat/NN ,/, subsequently/RB to/TO their/PRP$ deposition/NN and/CC consolidation/NN ./. MOLLUSCA/NNP ,/, One/CD of/IN the/DT great/JJ divisions/NNS of/IN the/DT animal/NN kingdom/NN ,/, including/VBG those/DT animals/NNS which/WDT have/VBP a/DT soft/JJ body/NN ,/, usually/RB furnished/VBN with/IN a/DT shell/NN ,/, and/CC in/IN which/WDT the/DT nervous/JJ ganglia/NN ,/, or/CC centres/NNS ,/, present/JJ no/DT definite/JJ general/JJ arrangement/NN ./. They/PRP are/VBP generally/RB known/VBN under/IN the/DT denomination/NN of/IN "/" shellfish/NN "/" ;/: the/DT cuttle/NN fish/NN ,/, and/CC the/DT common/JJ snails/NNS ,/, whelks/NNS ,/, oysters/NNS ,/, mussels/NNS ,/, and/CC cockles/NNS ,/, may/MD serve/VB as/IN examples/NNS of/IN them/PRP ./. MONOCOTYLEDONS/NNP ,/, or/CC MONOCOTYLEDONOUS/NNP PLANTS/NNS ,/, Plants/NNS in/IN which/WDT the/DT seed/NN sends/VBZ up/IN only/RB a/DT single/JJ seed/NN leaf/NN (/( or/CC cotyledon/NN )/SYM ;/: characterised/VBN by/IN the/DT absence/NN of/IN consecutive/JJ layers/NNS of/IN wood/NN in/IN the/DT stem/VB (/( endogenous/JJ growth/NN )/SYM ,/, by/IN the/DT veins/NNS of/IN the/DT leaves/VBZ being/VBG generally/RB straight/JJ ,/, and/CC by/IN the/DT parts/NNS of/IN the/DT flowers/NNS being/VBG generally/RB in/IN multiples/NNS of/IN three/CD ./. (/( Examples/NNS ,/, grasses/NNS ,/, lilies/NNS ,/, orchids/NNS ,/, palms/NNS ,/, &c/NN ./. )/SYM MORAINES/NNP ,/, The/DT accumulations/NNS of/IN fragments/NNS of/IN rock/NN brought/VBN down/RB by/IN glaciers/NNS ./. MORPHOLOGY/NNP ,/, The/DT law/NN of/IN form/NN or/CC structure/NN independent/JJ of/IN function/NN ./. MYSIS/NNP STAGE/NNP ,/, A/DT stage/NN in/IN the/DT development/NN of/IN certain/JJ crustaceans/NNS (/( prawns/NNS )/SYM ,/, in/IN which/WDT they/PRP closely/RB resemble/VB the/DT adults/NNS of/IN a/DT genus/NN (/( Mysis/NNP )/SYM belonging/VBG to/TO a/DT slightly/RB lower/JJR group/NN ./. NASCENT/NNP ,/, Commencing/VBG development/NN ./. NATATORY/NNP ,/, Adapted/VBN for/IN the/DT purpose/NN of/IN swimming/VBG ./. NAUPLIUS/NNP FORM/NNP ,/, The/DT earliest/JJS stage/NN in/IN the/DT development/NN of/IN many/JJ Crustacea/NNP ,/, especially/RB belonging/VBG to/TO the/DT lower/JJR groups/NNS ./. In/IN this/DT stage/NN the/DT animal/NN has/VBZ a/DT short/JJ body/NN ,/, with/IN indistinct/JJ indications/NNS of/IN a/DT division/NN into/IN segments/NNS ,/, and/CC three/CD pairs/NNS of/IN fringed/VBN limbs/NNS ./. This/DT form/NN of/IN the/DT common/JJ fresh/JJ water/NN cyclops/NNS was/VBD described/VBN as/IN a/DT distinct/JJ genus/NN under/IN the/DT name/NN of/IN Nauplius/NNP ./. NEURATION/NNP ,/, The/DT arrangement/NN of/IN the/DT veins/NNS or/CC nervures/NNS in/IN the/DT wings/NNS of/IN insects/NNS ./. NEUTERS/NNP ,/, Imperfectly/RB developed/VBN females/NNS of/IN certain/JJ social/JJ insects/NNS (/( such/JJ as/IN ants/NNS and/CC bees/NNS )/SYM ,/, which/WDT perform/VB all/DT the/DT labours/NNS of/IN the/DT community/NN ./. Hence/RB ,/, they/PRP are/VBP also/RB called/VBN workers/NNS ./. NICTITATING/NNP MEMBRANE/NNP ,/, A/DT semi/NN transparent/JJ membrane/NN ,/, which/WDT can/MD be/VB drawn/VBN across/IN the/DT eye/NN in/IN birds/NNS and/CC reptiles/NNS ,/, either/DT to/TO moderate/JJ the/DT effects/NNS of/IN a/DT strong/JJ light/NN or/CC to/TO sweep/NN particles/NNS of/IN dust/NN ,/, &c/NN ./. ,/, from/IN the/DT surface/NN of/IN the/DT eye/NN ./. OCELLI/NNP ,/, The/DT simple/JJ eyes/NNS or/CC stemmata/NN of/IN insects/NNS ,/, usually/RB situated/VBN on/IN the/DT crown/NN of/IN the/DT head/NN between/IN the/DT great/JJ compound/NN eyes/NNS ./. OESOPHAGUS/NNP ,/, The/DT gullet/NN ./. OOLITIC/NNP ,/, A/DT great/JJ series/NN of/IN secondary/JJ rocks/NNS ,/, so/RB called/VBN from/IN the/DT texture/NN of/IN some/DT of/IN its/PRP$ members/NNS ,/, which/WDT appear/VB to/TO be/VB made/VBN up/IN of/IN a/DT mass/NN of/IN small/JJ egg/NN like/IN calcareous/JJ bodies/NNS ./. OPERCULUM/NNP ,/, A/DT calcareous/JJ plate/NN employed/VBN by/IN many/JJ Molluscae/NNP to/TO close/VB the/DT aperture/NN of/IN their/PRP$ shell/NN ./. The/DT opercular/JJ valves/NNS of/IN cirripedes/NNS are/VBP those/DT which/WDT close/VB the/DT aperture/NN of/IN the/DT shell/NN ./. ORBIT/NNP ,/, The/DT bony/JJ cavity/NN for/IN the/DT reception/NN of/IN the/DT eye/NN ./. ORGANISM/NNP ,/, An/DT organised/VBD being/VBG ,/, whether/IN plant/NN or/CC animal/NN ./. ORTHOSPERMOUS/NNP ,/, A/DT term/NN applied/VBN to/TO those/DT fruits/NNS of/IN the/DT Umbelliferae/NNP which/WDT have/VBP the/DT seed/NN straight/JJ ./. OSCULANT/NNP ,/, Forms/NNPS or/CC groups/NNS apparently/RB intermediate/JJ between/IN and/CC connecting/VBG other/JJ groups/NNS are/VBP said/VBD to/TO be/VB osculant/NN ./. OVA/NNP ,/, Eggs/NNP ./. OVARIUM/NNP or/CC OVARY/NNP (/( in/IN plants/NNS )/SYM ,/, The/DT lower/JJR part/NN of/IN the/DT pistil/NN or/CC female/JJ organ/NN of/IN the/DT flower/NN ,/, containing/VBG the/DT ovules/NNS or/CC incipient/JJ seeds/NNS ;/: by/IN growth/NN after/IN the/DT other/JJ organs/NNS of/IN the/DT flower/NN have/VBP fallen/VBN ,/, it/PRP usually/RB becomes/VBZ converted/VBN into/IN the/DT fruit/NN ./. OVIGEROUS/NNP ,/, Egg/NNP bearing/VBG ./. OVULES/NNP (/( of/IN plants/NNS )/SYM ,/, The/DT seeds/NNS in/IN the/DT earliest/JJS condition/NN ./. PACHYDERMS/NNP ,/, A/DT group/NN of/IN Mammalia/NNP ,/, so/RB called/VBN from/IN their/PRP$ thick/JJ skins/NNS ,/, and/CC including/VBG the/DT elephant/NN ,/, rhinoceros/NN ,/, hippopotamus/JJ ,/, &c/NN ./. PALAEOZOIC/NNP ,/, The/DT oldest/JJS system/NN of/IN fossiliferous/JJ rocks/NNS ./. PALPI/NNP ,/, Jointed/VBN appendages/NNS to/TO some/DT of/IN the/DT organs/NNS of/IN the/DT mouth/NN in/IN insects/NNS and/CC Crustacea/NNP ./. PAPILIONACEAE/NNP ,/, An/DT order/NN of/IN plants/NNS (/( see/VB LEGUMINOSAE/NNP )/SYM ,/, The/DT flowers/NNS of/IN these/DT plants/NNS are/VBP called/VBN papilionaceous/JJ ,/, or/CC butterfly/NN like/IN ,/, from/IN the/DT fancied/VBD resemblance/NN of/IN the/DT expanded/VBN superior/JJ petals/NNS to/TO the/DT wings/NNS of/IN a/DT butterfly/NN ./. PARASITE/NNP ,/, An/DT animal/NN or/CC plant/NN living/VBG upon/IN or/CC in/IN ,/, and/CC at/IN the/DT expense/NN of/IN ,/, another/DT organism/NN ./. PARTHENOGENESIS/NNP ,/, The/DT production/NN of/IN living/VBG organisms/NNS from/IN unimpregnated/VBN eggs/NNS or/CC seeds/NNS ./. PEDUNCULATED/NNP ,/, Supported/VBN upon/IN a/DT stem/VB or/CC stalk/VBP ./. The/DT pedunculated/VBN oak/NN has/VBZ its/PRP$ acorns/NNS borne/VBN upon/IN a/DT footstool/NN ./. PELORIA/NNP or/CC PELORISM/NNP ,/, The/DT appearance/NN of/IN regularity/NN of/IN structure/NN in/IN the/DT flowers/NNS of/IN plants/NNS which/WDT normally/RB bear/VB irregular/JJ flowers/NNS ./. PELVIS/NNP ,/, The/DT bony/JJ arch/NN to/TO which/WDT the/DT hind/JJ limbs/NNS of/IN vertebrate/JJ animals/NNS are/VBP articulated/VBN ./. PETALS/NNP ,/, The/DT leaves/VBZ of/IN the/DT corolla/NN ,/, or/CC second/JJ circle/NN of/IN organs/NNS in/IN a/DT flower/NN ./. They/PRP are/VBP usually/RB of/IN delicate/JJ texture/NN and/CC brightly/RB coloured/JJ ./. PHYLLODINEOUS/NNP ,/, Having/VBG flattened/VBN ,/, leaf/NN like/IN twigs/NNS or/CC leafstalks/NNS instead/RB of/IN true/JJ leaves/VBZ ./. PIGMENT/NNP ,/, The/DT colouring/VBG material/NN produced/VBN generally/RB in/IN the/DT superficial/JJ parts/NNS of/IN animals/NNS ./. The/DT cells/NNS secreting/VBG it/PRP are/VBP called/VBN pigment/NN cells/NNS ./. PINNATE/NNP ,/, Bearing/VBG leaflets/NNS on/IN each/DT side/NN of/IN a/DT central/JJ stalk/VBP ./. PISTILS/NNP ,/, The/DT female/JJ organs/NNS of/IN a/DT flower/NN ,/, which/WDT occupy/VB a/DT position/NN in/IN the/DT centre/NN of/IN the/DT other/JJ floral/JJ organs/NNS ./. The/DT pistil/NN is/VBZ generally/RB divisible/JJ into/IN the/DT ovary/JJ or/CC germen/NN ,/, the/DT style/NN and/CC the/DT stigma/NN ./. PLACENTALIA/NNP ,/, PLACENTATA/NNP ,/, or/CC Placental/NNP Mammals/NNP ,/, See/VB MAMMALIA/NNP ./. PLANTIGRADES/NNP ,/, Quadrupeds/NNP which/WDT walk/VB upon/IN the/DT whole/JJ sole/JJ of/IN the/DT foot/NN ,/, like/IN the/DT bears/VBZ ./. PLASTIC/NN ,/, Readily/RB capable/JJ of/IN change/NN ./. PLEISTOCENE/NNP PERIOD/NN ,/, The/DT latest/JJS portion/NN of/IN the/DT Tertiary/NNP epoch/NN ./. PLUMULE/NNP (/( in/IN plants/NNS )/SYM ,/, The/DT minute/NN bud/NN between/IN the/DT seed/NN leaves/VBZ of/IN newly/RB germinated/JJ plants/NNS ./. PLUTONIC/NNP ROCKS/NNP ,/, Rocks/NNP supposed/VBN to/TO have/VB been/VBN produced/VBN by/IN igneous/JJ action/NN in/IN the/DT depths/NNS of/IN the/DT earth/NN ./. POLLEN/NNP ,/, The/DT male/JJ element/NN in/IN flowering/NN plants/NNS ;/: usually/RB a/DT fine/JJ dust/NN produced/VBN by/IN the/DT anthers/NNS ,/, which/WDT ,/, by/IN contact/NN with/IN the/DT stigma/NN effects/NNS the/DT fecundation/NN of/IN the/DT seeds/NNS ./. This/DT impregnation/NN is/VBZ brought/VBN about/IN by/IN means/VBZ of/IN tubes/NNS (/( pollen/NN tubes/NNS )/SYM which/WDT issue/NN from/IN the/DT pollen/NN grains/NNS adhering/VBG to/TO the/DT stigma/NN ,/, and/CC penetrate/VB through/IN the/DT tissues/NNS until/IN they/PRP reach/VB the/DT ovary/JJ ./. POLYANDROUS/NNP (/( flowers/NNS )/SYM ,/, Flowers/NNPS having/VBG many/JJ stamens/NNS ./. POLYGAMOUS/NNP PLANTS/NNS ,/, Plants/NNS in/IN which/WDT some/DT flowers/NNS are/VBP unisexual/JJ and/CC others/NNS hermaphrodite/NN ./. The/DT unisexual/JJ (/( male/JJ and/CC female/JJ )/SYM flowers/NNS ,/, may/MD be/VB on/IN the/DT same/JJ or/CC on/IN different/JJ plants/NNS ./. POLYMORPHIC/NNP ,/, Presenting/VBG many/JJ forms/NNS ./. POLYZOARY/NNP ,/, The/DT common/JJ structure/NN formed/VBN by/IN the/DT cells/NNS of/IN the/DT Polyzoa/NNP ,/, such/JJ as/IN the/DT well/RB known/VBN seamats/NNS ./. PREHENSILE/NNP ,/, Capable/JJ of/IN grasping/VBG ./. PREPOTENT/NNP ,/, Having/VBG a/DT superiority/NN of/IN power/NN ./. PRIMARIES/NNP ,/, The/DT feathers/NNS forming/VBG the/DT tip/NN of/IN the/DT wing/NN of/IN a/DT bird/NN ,/, and/CC inserted/VBN upon/IN that/IN part/NN which/WDT represents/VBZ the/DT hand/NN of/IN man/NN ./. PROCESSES/NNP ,/, Projecting/VBG portions/NNS of/IN bones/NNS ,/, usually/RB for/IN the/DT attachment/NN of/IN muscles/NNS ,/, ligaments/NNS ,/, &c/NN ./. PROPOLIS/NNP ,/, A/DT resinous/JJ material/NN collected/VBN by/IN the/DT hivebees/NNS from/IN the/DT opening/NN buds/NNS of/IN various/JJ trees/NNS ./. PROTEAN/NNP ,/, Exceedingly/RB variable/JJ ./. PROTOZOA/NNP ,/, The/DT lowest/JJS great/JJ division/NN of/IN the/DT animal/NN kingdom/NN ./. These/DT animals/NNS are/VBP composed/VBN of/IN a/DT gelatinous/JJ material/NN ,/, and/CC show/NN scarcely/RB any/DT trace/NN of/IN distinct/JJ organs/NNS ./. The/DT Infusoria/NNP ,/, Foraminifera/NNP ,/, and/CC sponges/NNS ,/, with/IN some/DT other/JJ forms/NNS ,/, belong/VB to/TO this/DT division/NN ./. PUPA/NNP (/( pl/NN ./. Pupae/NNP )/SYM ,/, The/DT second/JJ stage/NN in/IN the/DT development/NN of/IN an/DT insect/NN ,/, from/IN which/WDT it/PRP emerges/VBZ in/IN the/DT perfect/JJ (/( winged/VBD )/SYM reproductive/JJ form/NN ./. In/IN most/RBS insects/NNS the/DT pupal/JJ stage/NN is/VBZ passed/VBN in/IN perfect/JJ repose/NN ./. The/DT chrysalis/NN is/VBZ the/DT pupal/JJ state/NN of/IN butterflies/NNS ./. RADICLE/NNP ,/, The/DT minute/NN root/NN of/IN an/DT embryo/NN plant/NN ./. RAMUS/NNP ,/, One/CD half/NN of/IN the/DT lower/JJR jaw/NN in/IN the/DT Mammalia/NNP ./. The/DT portion/NN which/WDT rises/VBZ to/TO articulate/JJ with/IN the/DT skull/NN is/VBZ called/VBN the/DT ascending/VBG ramus/JJ ./. RANGE/NNP ,/, The/DT extent/NN of/IN country/NN over/IN which/WDT a/DT plant/NN or/CC animal/NN is/VBZ naturally/RB spread/NN ./. Range/NN in/IN time/NN expresses/VBZ the/DT distribution/NN of/IN a/DT species/NN or/CC group/NN through/IN the/DT fossiliferous/JJ beds/NNS of/IN the/DT earth's/NNS crust/NN ./. RETINA/NNP ,/, The/DT delicate/JJ inner/JJ coat/NN of/IN the/DT eye/NN ,/, formed/VBN by/IN nervous/JJ filaments/NNS spreading/VBG from/IN the/DT optic/JJ nerve/NN ,/, and/CC serving/VBG for/IN the/DT perception/NN of/IN the/DT impressions/NNS produced/VBN by/IN light/NN ./. RETROGRESSION/NNP ,/, Backward/NNP development/NN ./. When/WRB an/DT animal/NN ,/, as/IN it/PRP approaches/NNS maturity/NN ,/, becomes/VBZ less/JJR perfectly/RB organised/VBD than/IN might/MD be/VB expected/VBN from/IN its/PRP$ early/JJ stages/NNS and/CC known/VBN relationships/NNS ,/, it/PRP is/VBZ said/VBD to/TO undergo/VB a/DT retrograde/JJ development/NN or/CC metamorphosis/NN ./. RHIZOPODS/NNP ,/, A/DT class/NN of/IN lowly/JJ organised/VBD animals/NNS (/( Protozoa/NNP )/SYM ,/, having/VBG a/DT gelatinous/JJ body/NN ,/, the/DT surface/NN of/IN which/WDT can/MD be/VB protruded/VBD in/IN the/DT form/NN of/IN root/NN like/IN processes/NNS or/CC filaments/NNS ,/, which/WDT serve/VB for/IN locomotion/NN and/CC the/DT prehension/NN of/IN food/NN ./. The/DT most/RBS important/JJ order/NN is/VBZ that/IN of/IN the/DT Foraminifera/NNP ./. RODENTS/NNP ,/, The/DT gnawing/NN Mammalia/NNP ,/, such/JJ as/IN the/DT rats/NNS ,/, rabbits/NNS ,/, and/CC squirrels/NNS ./. They/PRP are/VBP especially/RB characterised/VBN by/IN the/DT possession/NN of/IN a/DT single/JJ pair/NN of/IN chisel/NN like/IN cutting/VBG teeth/NNS in/IN each/DT jaw/NN ,/, between/IN which/WDT and/CC the/DT grinding/VBG teeth/NNS there/EX is/VBZ a/DT great/JJ gap/NN ./. RUBUS/NNP ,/, The/DT bramble/NN genus/NN ./. RUDIMENTARY/NNP ,/, Very/RB imperfectly/RB developed/VBN ./. RUMINANTS/NNP ,/, The/DT group/NN of/IN quadrupeds/NNS which/WDT ruminate/VB or/CC chew/VB the/DT cud/NN ,/, such/JJ as/IN oxen/NNS ,/, sheep/NN ,/, and/CC deer/NN ./. They/PRP have/VBP divided/VBN hoofs/NNS ,/, and/CC are/VBP destitute/JJ of/IN front/NN teeth/NNS in/IN the/DT upper/JJ jaw/NN ./. SACRAL/NNP ,/, Belonging/VBG to/TO the/DT sacrum/NN ,/, or/CC the/DT bone/NN composed/VBN usually/RB of/IN two/CD or/CC more/JJR united/VBN vertebrae/NNS to/TO which/WDT the/DT sides/NNS of/IN the/DT pelvis/NN in/IN vertebrate/JJ animals/NNS are/VBP attached/VBN ./. SARCODE/NNP ,/, The/DT gelatinous/JJ material/NN of/IN which/WDT the/DT bodies/NNS of/IN the/DT lowest/JJS animals/NNS (/( Protozoa/NNP )/SYM are/VBP composed/VBN ./. SCUTELLAE/NNP The/DT horny/JJ plates/NNS with/IN which/WDT the/DT feet/NNS of/IN birds/NNS are/VBP generally/RB more/JJR or/CC less/JJR covered/VBN ,/, especially/RB in/IN front/NN ./. SEDIMENTARY/NNP FORMATIONS/NNP ,/, Rocks/NNP deposited/VBN as/IN sediments/NNS from/IN water/NN ./. SEGMENTS/NNP ,/, The/DT transverse/JJ rings/NNS of/IN which/WDT the/DT body/NN of/IN an/DT articulate/JJ animal/NN or/CC annelid/JJ is/VBZ composed/VBN ./. SEPALS/NNP ,/, The/DT leaves/VBZ or/CC segments/NNS of/IN the/DT calyx/NN ,/, or/CC outermost/JJ envelope/NN of/IN an/DT ordinary/JJ flower/NN ./. They/PRP are/VBP usually/RB green/JJ ,/, but/CC sometimes/RB brightly/RB coloured/JJ ./. SERRATURES/NNP ,/, Teeth/NNS like/IN those/DT of/IN a/DT saw/VBD ./. SESSILE/NNP ,/, Not/RB supported/VBN on/IN a/DT stem/VB or/CC footstalk/NN ./. SILURIAN/NNP SYSTEM/NNP ,/, A/DT very/RB ancient/JJ system/NN of/IN fossiliferous/JJ rocks/NNS belonging/VBG to/TO the/DT earlier/RBR part/NN of/IN the/DT Palaeozoic/NNP series/NN ./. SPECIALISATION/NNP ,/, The/DT setting/VBG apart/RB of/IN a/DT particular/JJ organ/NN for/IN the/DT performance/NN of/IN a/DT particular/JJ function/NN ./. SPINAL/NNP CORD/NNP ,/, The/DT central/JJ portion/NN of/IN the/DT nervous/JJ system/NN in/IN the/DT Vertebrata/NNP ,/, which/WDT descends/VBZ from/IN the/DT brain/NN through/IN the/DT arches/NNS of/IN the/DT vertebrae/NNS ,/, and/CC gives/VBZ off/IN nearly/RB all/DT the/DT nerves/NNS to/TO the/DT various/JJ organs/NNS of/IN the/DT body/NN ./. STAMENS/NNP ,/, The/DT male/JJ organs/NNS of/IN flowering/NN plants/NNS ,/, standing/VBG in/IN a/DT circle/NN within/IN the/DT petals/NNS ./. They/PRP usually/RB consist/VB of/IN a/DT filament/NN and/CC an/DT anther/NN ,/, the/DT anther/NN being/VBG the/DT essential/JJ part/NN in/IN which/WDT the/DT pollen/NN ,/, or/CC fecundating/VBG dust/NN ,/, is/VBZ formed/VBN ./. STERNUM/NNP ,/, The/DT breast/NN bone/NN ./. STIGMA/NNP ,/, The/DT apical/JJ portion/NN of/IN the/DT pistil/NN in/IN flowering/NN plants/NNS ./. STIPULES/NNP ,/, Small/JJ leafy/JJ organs/NNS placed/VBN at/IN the/DT base/NN of/IN the/DT footstalks/NNS of/IN the/DT leaves/VBZ in/IN many/JJ plants/NNS ./. STYLE/NNP ,/, The/DT middle/NN portion/NN of/IN the/DT perfect/JJ pistil/NN ,/, which/WDT rises/VBZ like/IN a/DT column/NN from/IN the/DT ovary/JJ and/CC supports/VBZ the/DT stigma/NN at/IN its/PRP$ summit/NN ./. SUBCUTANEOUS/NNP ,/, Situated/VBN beneath/IN the/DT skin/NN ./. SUCTORIAL/NNP ,/, Adapted/VBN for/IN sucking/VBG ./. SUTURES/NNP (/( in/IN the/DT skull/NN )/SYM ,/, The/DT lines/NNS of/IN junction/NN of/IN the/DT bones/NNS of/IN which/WDT the/DT skull/NN is/VBZ composed/VBN ./. TARSUS/NNP (/( pl/NN ./. TARSI/NNP )/SYM ,/, The/DT jointed/VBN feet/NNS of/IN articulate/JJ animals/NNS ,/, such/JJ as/IN insects/NNS ./. TELEOSTEAN/NNP FISHES/NNP ,/, Fishes/NNP of/IN the/DT kind/NN familiar/JJ to/TO us/PRP in/IN the/DT present/JJ day/NN ,/, having/VBG the/DT skeleton/NN usually/RB completely/RB ossified/VBN and/CC the/DT scales/NNS horny/JJ ./. TENTACULA/NNP or/CC TENTACLES/NNP ,/, Delicate/NNP fleshy/JJ organs/NNS of/IN prehension/NN or/CC touch/NN possessed/VBD by/IN many/JJ of/IN the/DT lower/JJR animals/NNS ./. TERTIARY/NNP ,/, The/DT latest/JJS geological/JJ epoch/NN ,/, immediately/RB preceding/VBG the/DT establishment/NN of/IN the/DT present/JJ order/NN of/IN things/NNS ./. TRACHEA/NNP ,/, The/DT windpipe/NN or/CC passage/NN for/IN the/DT admission/NN of/IN air/NN to/TO the/DT lungs/NNS ./. TRIDACTYLE/NNP ,/, Three/CD fingered/VBD ,/, or/CC composed/VBN of/IN three/CD movable/JJ parts/NNS attached/VBN to/TO a/DT common/JJ base/NN ./. TRILOBITES/NNP ,/, A/DT peculiar/JJ group/NN of/IN extinct/JJ crustaceans/NNS ,/, somewhat/RB resembling/VBG the/DT woodlice/NN in/IN external/JJ form/NN ,/, and/CC ,/, like/IN some/DT of/IN them/PRP ,/, capable/JJ of/IN rolling/VBG themselves/PRP up/IN into/IN a/DT ball/NN ./. Their/PRP$ remains/VBZ are/VBP found/VBD only/RB in/IN the/DT Palaeozoic/NNP rocks/NNS ,/, and/CC most/RBS abundantly/RB in/IN those/DT of/IN Silurian/NNP age/NN ./. TRIMORPHIC/NNP ,/, Presenting/VBG three/CD distinct/JJ forms/NNS ./. UMBELLIFERAE/NNP ,/, An/DT order/NN of/IN plants/NNS in/IN which/WDT the/DT flowers/NNS ,/, which/WDT contain/VB five/CD stamens/NNS and/CC a/DT pistil/NN with/IN two/CD styles/NNS ,/, are/VBP supported/VBN upon/IN footstalks/NNS which/WDT spring/NN from/IN the/DT top/JJ of/IN the/DT flower/NN stem/VB and/CC spread/NN out/IN like/IN the/DT wires/NNS of/IN an/DT umbrella/NN ,/, so/RB as/IN to/TO bring/VB all/DT the/DT flowers/NNS in/IN the/DT same/JJ head/NN (/( umbel/NN )/SYM nearly/RB to/TO the/DT same/JJ level/NN ./. (/( Examples/NNS ,/, parsley/NN and/CC carrot/NN ./. )/SYM UNGULATA/NNP ,/, Hoofed/VBN quadrupeds/NNS ./. UNICELLULAR/NNP ,/, Consisting/VBG of/IN a/DT single/JJ cell/NN ./. VASCULAR/NNP ,/, Containing/VBG blood/NN vessels/NNS ./. VERMIFORM/NNP ,/, Like/IN a/DT worm/NN ./. VERTEBRATA/NNP :/: or/CC VERTEBRATE/NNP ANIMALS/NNP ,/, The/DT highest/JJS division/NN of/IN the/DT animal/NN kingdom/NN ,/, so/RB called/VBN from/IN the/DT presence/NN in/IN most/RBS cases/NNS of/IN a/DT backbone/NN composed/VBN of/IN numerous/JJ joints/NNS or/CC vertebrae/NNS ,/, which/WDT constitutes/VBZ the/DT centre/NN of/IN the/DT skeleton/NN and/CC at/IN the/DT same/JJ time/NN supports/VBZ and/CC protects/VBZ the/DT central/JJ parts/NNS of/IN the/DT nervous/JJ system/NN ./. WHORLS/NNP ,/, The/DT circles/NNS or/CC spiral/NN lines/NNS in/IN which/WDT the/DT parts/NNS of/IN plants/NNS are/VBP arranged/VBN upon/IN the/DT axis/NN of/IN growth/NN ./. WORKERS/NNS ,/, See/VB neuters/NNS ./. ZOEA/NNP STAGE/NNP ,/, The/DT earliest/JJS stage/NN in/IN the/DT development/NN of/IN many/JJ of/IN the/DT higher/JJR Crustacea/NNP ,/, so/RB called/VBN from/IN the/DT name/NN of/IN Zoea/NNP applied/VBN to/TO these/DT young/JJ animals/NNS when/WRB they/PRP were/VBD supposed/VBN to/TO constitute/VB a/DT peculiar/JJ genus/NN ./. ZOOIDS/NNP ,/, In/IN many/JJ of/IN the/DT lower/JJR animals/NNS (/( such/JJ as/IN the/DT corals/NNS ,/, Medusae/NNP ,/, &c/NN ./. )/SYM reproduction/NN takes/VBZ place/NN in/IN two/CD ways/NNS ,/, namely/RB ,/, by/IN means/VBZ of/IN eggs/NNS and/CC by/IN a/DT process/NN of/IN budding/VBG with/IN or/CC without/IN separation/NN from/IN the/DT parent/NN of/IN the/DT product/NN of/IN the/DT latter/NN ,/, which/WDT is/VBZ often/RB very/RB different/JJ from/IN that/IN of/IN the/DT egg/NN ./. The/DT individuality/NN of/IN the/DT species/NN is/VBZ represented/VBN by/IN the/DT whole/JJ of/IN the/DT form/NN produced/VBN between/IN two/CD sexual/JJ reproductions/NNS ;/: and/CC these/DT forms/NNS ,/, which/WDT are/VBP apparently/RB individual/JJ animals/NNS ,/, have/VBP been/VBN called/VBN zooide/NN ./. END/NNP GLOSSARY/NNP ./.