AuthorofJournalofresearchesduringH。M。S。Beagle’sVoyageroundtheworld。London：JohnMurray，AlbemarleStreet，1859

PrefaceFIRSTEDITIONOFTHISWORKANHISTORICALSKETCHOFTHEPROGRESSOFOPINION

ONTHEORIGINOFSPECIESPREVIOUSLYTOTHEPUBLICATIONOFTHEFIRSTEDITION

OFTHISWORK

IWILLheregiveabriefsketchoftheprogressofopinionontheOriginofSpecies。Untilrecentlythegreatmajorityofnaturalistsbelievedthatspecieswereimmutableproductions，andhadbeenseparatelycreated。Thisviewhasbeenablymaintainedbymanyauthors。Somefewnaturalists，ontheotherhand，havebelievedthatspeciesundergomodification，andthattheexistingformsoflifearethedescendantsbytruegenerationofpre-existingforms。Passingoverallusionstothesubjectintheclassicalwriters，*

thefirstauthorwhoinmoderntimeshastreateditinascientificspiritwasBuffon。Butashisopinionsfluctuatedgreatlyatdifferentperiods，andashedoesnotenteronthecauses*Aristotle，inhis’PhysicaeAuscultationes’

(lib。2，cap。8，s。2)，afterremarkingthatraindoesnotfallinordertomakethecorngrow，anymorethanitfallstospoilthefarmer’scornwhenthreshedoutofdoors，appliesthesameargumenttoorganization：

andadds(astranslatedbyMrClairGrece，whofirstpointedoutthepassagetome)，’Sowhathindersthedifferentparts[ofthebody]fromhavingthismerelyaccidentalrelationinnature？astheteeth，forexample，growbynecessity，thefrontonessharp，adaptedfordividing，andthegrindersflat，andserviceableformasticatingthefood。sincetheywerenotmadeforthesakeofthis，butitwastheresultofaccident。Andinlikemannerastotheotherpartsinwhichthereappearstoexistanadaptationtoanend。Wheresoever，therefore，allthingstogether(thatisallthepartsofonewhole)happenedlikeasiftheyweremadeforthesakeofsomething，thesewerepreserved，havingbeenappropriatelyconstitutedbyaninternalspontaneity，andwhatsoeverthingswerenotthusconstituted，perished，andstillperish。ormeansofthetransformationofspecies，Ineednothereenterondetails。

Lamarckwasthefirstmanwhoseconclusionsonthesubjectexcitedmuchattention。Thisjustly-celebratednaturalistfirstpublishedhisviewsin1801。hemuchenlargedthemin1809inhisPhilosophieZoologique，’

andsubsequently，in1815，intheIntroductiontohisHist。Nat。desAnimauxsansVert&eacute。bres。’Intheseworksheupholdsthedoctrinethatspecies，includingman，aredescendedfromotherspecies。Hefirstdidtheeminentserviceofarousingattentiontotheprobabilityofallchangeintheorganic，aswellasintheinorganicworld，beingtheresultoflaw，andnotofmiraculousinterposition。Lamarckseemstohavebeenchieflyledtohisconclusiononthegradualchangeofspecies，bythedifficultyofdistinguishingspeciesandvarieties，bythealmostperfectgradationofformsincertaingroups，andbytheanalogyofdomesticproductions。Withrespecttothemeansofmodification，heattributedsomethingtothedirectactionofthephysicalconditionsoflife，somethingtothecrossingofalreadyexistingforms，andmuchtouseanddisuse，thatis，totheeffectsofhabit。Tothislatteragencyheseemedtoattributeallthebeautifuladaptationsinnature。&amp。mdash。suchasthelongneckofthegiraffeforbrowsingonthebranchesoftrees。Buthelikewisebelievedinalawofprogressivedevelopment。andasalltheformsoflifethustendtoprogress，inordertoaccountfortheexistenceatthepresentdayofsimpleproductions，hemaintainsthatsuchformsarenowspontaneouslygenerated。*

Wehereseetheprincipleofnaturalselectionshadowedforth，buthowlittleAristotlefullycomprehendedtheprinciple，isshownbyhisremarksontheformationoftheteeth。*IhavetakenthedateofthefirstpublicationofLamarckfromIsid。GeoffroySaint-Hilaire’s(’Hist。Nat。G&eacute。n&eacute。rale，’

tom。ii。p。405，1859)excellenthistoryofopiniononthissubject。InthisworkafullaccountisgivenofBuffon’sconclusionsonthesamesubject。

Itiscurioushowlargelymygrandfather，DrErasmusDarwin，anticipatedtheviewsanderroneousgroundsofopinionofLamarckinhis’Zoonomia’

(vol。i。pp。500-510)，publishedin1794。AccordingtoIsid。GeoffroythereisnodoubtthatGoethewasanextremepartisanofsimilarviews，asshownintheIntroductiontoaworkwrittenin1794and1795，butnotpublishedtilllongafterwards：hehaspointedlyremarked(’GoethealsNaturforscher，’

vonDrKarlMedinges。34)thatthefuturequestionfornaturalistswillbehow，forinstance，cattlegottheirhorns，andnotforwhattheyareused。Itisratherasingularinstanceofthemannerinwhichsimilarviewsariseataboutthesametime，thatGoetheinGermany，DrDarwininEngland，andGeoffroySaint-Hilaire(asweshallimmediatelysee)inFrance。cametothesameconclusionontheoriginofspecies，intheyears1794-5。

GeoffroySaint-Hilaire，asisstatedinhis’Life，’writtenbyhisson，suspected，asearlyas1795，thatwhatwecallspeciesarevariousdegenerationsofthesametype。Itwasnotuntil1828thathepublishedhisconvictionthatthesameformshavenotbeenperpetuatedsincetheoriginofallthings。

Geoffroyseemstohavereliedchieflyontheconditionsoflife，orthe’mondeambiant’asthecauseofchange。Hewascautiousindrawingconclusions，anddidnotbelievethatexistingspeciesarenowundergoingmodification。and，ashissonadds，C’estdoncunprobl&egrave。me&agrave。

r&eacute。serverenti&egrave。rement&agrave。l’avenir，suppos&eacute。memequel’avenirdoiveavoirprisesurlui。’

In1813，DrW。C。WellsreadbeforetheRoyalSociety’AnAccountofaWhitefemale，partofwhoseskinresembledthatofaNegro’。buthispaperwasnotpublisheduntilhisfamous’TwoEssaysuponDewandSingleVision’appearedin1818。Inthispaperhedistinctlyrecognisestheprincipleofnaturalselection，andthisisthefirstrecognitionwhichhasbeenindicated。butheappliesitonlytotheracesofman，andtocertaincharactersalone。Afterremarkingthatnegroesandmulattoesenjoyanimmunityfromcertaintropicaldiseases，heobserves，firstly，thatallanimalstendtovaryinsomedegree，and，secondly，thatagriculturistsimprovetheirdomesticatedanimalsbyselection。andthen，headds，butwhatisdoneinthislattercase’byart，seemstobedonewithequalefficacy，thoughmoreslowly，bynature，intheformationofvarietiesofmankind，fittedforthecountrywhichtheyinhabit。Oftheaccidentalvarietiesofman，whichwouldoccuramongthefirstfewandscatteredinhabitantsofthemiddleregionsofAfrica，someonewouldbebetterfittedthantheotherstobearthediseasesofthecountry。Thisracewouldconsequentlymultiply，whiletheotherswoulddecrease。notonlyfromtheirinabilitytosustaintheattacksofdisease，butfromtheirincapacityofcontendingwiththeirmorevigorousneighbours。ThecolourofthisvigorousraceItakeforgranted，fromwhathasbeenalreadysaid，wouldbedark。Butthesamedispositiontoformvarietiesstillexisting，adarkerandadarkerracewouldinthecourseoftimeoccur：andasthedarkestwouldbethebestfittedfortheclimate，thiswouldatlengthbecomethemostprevalent。ifnottheonlyrace，intheparticularcountryinwhichithadoriginated。’Hethenextendsthesesameviewstothewhiteinhabitantsofcolderclimates。IamindebtedtoMrRowley，oftheUnitedStates，forhavingcalledmyattention，throughMrBrace，totheabovepassageinDrWells’work。

TheHon。andRev。W。Herbert，afterwardsDeanofManchester，inthefourthvolumeofthe’HorticulturalTransactions，’1822，andinhisworkonthe’Amaryllidaceae’(1837，pp。19，339)，declaresthat’horticulturalexperimentshaveestablished，beyondthepossibilityofrefutation，thatbotanicalspeciesareonlyahigherandmorepermanentclassofvarieties。’

Heextendsthesameviewtoanimals。TheDeanbelievesthatsinglespeciesofeachgenuswerecreatedinanoriginallyhighlyplasticcondition，andthatthesehaveproduced，chieflybyintercrossing，butlikewisebyvariation，allourexistingspecies。

In1826ProfessorGrant，intheconcludingparagraphinhiswell-knownpaper(’Edinburghphilosophicaljournal，’vol。xiv。p。283)ontheSpongilla，clearlydeclareshisbeliefthatspeciesaredescendedfromotherspecies，andthattheybecomeimprovedinthecourseofmodification。Thissameviewwasgiveninhis55thLecture，publishedinthe’Lancet’in1834。

In1831MrPatrickMatthewpublishedhisworkon’NavalTimberandArboriculture，’

inwhichhegivespreciselythesameviewontheoriginofspeciesasthat(presentlytobealludedto)propoundedbyMrWallaceandmyselfinthe’Linneanjournal，’andasthatenlargedinthepresentvolume。UnfortunatelytheviewwasgivenbyMrMatthewverybrieflyinscatteredpassagesinanAppendixtoaworkonadifferentsubject，sothatitremainedunnoticeduntilMrMatthewhimselfdrewattentiontoitinthe’Gardener’sChronicle，’

onApril7th，1860。ThedifferencesofMrMatthew’sviewfromminearenotofmuchimportance。heseemstoconsiderthattheworldwasnearlydepopulatedatsuccessiveperiods，andthenre-stocked。andhegivesasanalternative，thatnewformsmaybegenerated’withoutthepresenceofanymouldorgermofformeraggregates。’IamnotsurethatIunderstandsomepassages。butitseemsthatheattributesmuchinfluencetothedirectactionoftheconditionsoflife。Heclearlysaw，however，thefullforceoftheprincipleofnaturalselection。

Thecelebratedgeologistandnaturalist，VonBuch，inhisexcellent’DescriptionphysiquedesIslesCanaries’(1836，p。147)，clearlyexpresseshisbeliefthatvarietiesslowlybecomechangedintopermanentspecies，whicharenolongercapableofintercrossing。

Rafinesque，inhis’NewFloraofNorthAmerica，’publishedin1836，wrote(p。6)asfollows：-’Allspeciesmighthavebeenvarietiesonce，andmanyvarietiesaregraduallybecomingspeciesbyassumingconstantandpeculiarcharacters’。butfartheron(p。18)headds，’excepttheoriginaltypesorancestorsofthegenus。’

In1843-44ProfessorHaldeman(’BostonjournalofNat。Hist。U。States，vol。iv。p。468)hasablygiventheargumentsforandagainstthehypothesisofthedevelopmentandmodificationofspecies：heseemstoleantowardsthesideofchange。

The’VestigesofCreation’appearedin1844。Inthetenthandmuchimprovededition(1853)theanonymousauthorsays(p。155)：-’Thepropositiondeterminedonaftermuchconsiderationis，thattheseveralseriesofanimatedbeings，fromthesimplestandoldestuptothehighestandmostrecent，are，undertheprovidenceofGod，theresults，first，ofanimpulsewhichhasbeenimpartedtotheformsoflife，advancingthem，indefinitetimes，bygeneration，throughgradesoforganisationterminatinginthehighestdicotyledons-andvertebrata，thesegradesbeingfewinnumber，andgenerallymarkedbyintervalsoforganiccharacter，whichwefindtobeapracticaldifficultyinascertainingaffinities。second，ofanotherimpulseconnectedwiththevitalforces，tending，inthecourseofgenerations，tomodifyorganicstructuresinaccordancewithexternalcircumstances，asfood，thenatureofthehabitat，andthemeteoricagencies，thesebeingthe’’adaptations’’ofthenaturaltheologian。’Theauthorapparentlybelievesthatorganisationprogressesbysuddenleaps，butthattheeffectsproducedbytheconditionsoflifearegradual。Heargueswithmuchforceongeneralgroundsthatspeciesarenotimmutableproductions。ButIcannotseehowthetwosupposed’impulses’accountinascientificsenseforthenumerousandbeautifulco-adaptationswhichweseethroughoutnature。Icannotseethatwethusgainanyinsighthow，forinstance，awoodpeckerhasbecomeadaptedtoitspeculiarhabitsofLife。Thework，fromitspowerfulandbrilliantstyle，thoughdisplayingintheearliereditionslittleaccurateknowledgeandagreatwantofscientificcaution，immediatelyhadaverywidecirculation。Inmyopinionithasdoneexcellentserviceinthiscountryincallingattentiontothesubject，inremovingprejudice，andinthuspreparingthegroundforthereceptionofanalogousviews。

In1846theveterangeologistN。J。d’Omaliusd’Halloypublishedinanexcellentthoughshortpaper(Bulletinsdel’Acad。RoyBruxelles，’

tom。xiii。p。581)hisopinionthatitismoreprobablethatnewspecieshavebeenproducedbydescentwithmodificationthanthattheyhavebeenseparatelycreated：theauthorfirstpromulgatedthisopinionin1831。

ProfessorOwen，in1849(’NatureofLimbs，’p。86)，wroteasfollows：-

Thearchetypalideawasmanifestedinthefleshunderdiversesuchmodifications，uponthisplanet，longpriortotheexistenceofthoseanimalspeciesthatactuallyexemplifyit。Towhatnaturallawsorsecondarycausestheorderlysuccessionandprogressionofsuchorganicphenomenamayhavebeencommitted，we，asyet，areignorant。’InhisAddresstotheBritishAssociation，in1858，hespeaks(p。li。)oftheaxiomofthecontinuousoperationofcreativepower，oroftheordainedbecomingoflivingthings。’Fartheron(p。xc。)，afterreferringtogeographicaldistribution，headds，’ThesephenomenashakeourconfidenceintheconclusionthattheApteryxofNewZealandandtheRedGrouseofEnglandweredistinctcreationsinandforthoseislandsrespectively。Always，also，itmaybewelltobearinmindthatbytheword’’creation’’thezoologistmeans’aprocessheknowsnotwhat。’’

HeamplifiesthisideabyaddingthatwhensuchcasesasthatoftheRedGrouseareenumeratedbythezoologistsasevidenceofdistinctcreationofthebirdinandforsuchislands，hechieflyexpressesthatheknowsnothowtheRedGrousecametobethere，andthereexclusively。signifyingalso，bythismodeofexpressingsuchignorance，hisbeliefthatboththebirdandtheislandsowedtheirorigintoagreatfirstCreativeCause。’

IfweinterpretthesesentencesgiveninthesameAddress，onebytheother，itappearsthatthiseminentphilosopherfeltin1858hisconfidenceshakenthattheApteryxandtheRedGrousefirstappearedintheirrespectivehomes，’heknewnothow，’orbysomeprocess’heknewnotwhat。’

ThisAddresswasdeliveredafterthepapersbyMrWallaceandmyselfontheOriginofSpecies，presentlytobereferredto，hadbeenreadbeforetheLinneanSociety。Whenthefirsteditionofthisworkwaspublished，Iwassocompletelydeceived，asweremanyothers，bysuchexpressionsas’thecontinuousoperationofcreativepower，’thatIincludedProfessorOwenwithotherpalaeontologistsasbeingfirmlyconvincedoftheimmutabilityofspecies。butitappears(’Anat。ofVertebrates，’vol。iii。p。796)thatthiswasonmypartapreposterouserror。InthelasteditionofthisworkIinferred，andtheinferencestillseemstomeperfectlyjust，fromapassagebeginningwiththewords’nodoubtthetype-form，’&amp。c。(Ibid。

vol。i。p。xxxv。)，thatProfessorOwenadmittedthatnaturalselectionmayhavedonesomethingintheformationofanewspecies。butthisitappears(Ibid。vol。nl。p。798)isinaccurateandwithoutevidence。IalsogavesomeextractsfromacorrespondencebetweenProfessorOwenandtheEditorofthe’LondonReview，’fromwhichitappearedmanifesttotheEditoraswellastomyself，thatProfessorOwenclaimedtohavepromulgatedthetheoryofnaturalselectionbeforeIhaddoneso。andIexpressedmysurpriseandsatisfactionatthisannouncement。butasfarasitispossibletounderstandcertainrecentlypublishedpassages(Ibid。vol。iii。p。798)

Ihaveeitherpartiallyorwhollyagainfallenintoerror。ItisconsolatorytomethatothersfindProfessorOwen’scontroversialwritingsasdifficulttounderstandandtoreconcilewitheachother，asIdo。Asfarasthemereenunciationoftheprincipleofnaturalselectionisconcerned，itisquiteimmaterialwhetherornotProfessorOwenprecededme，forbothofus，asshowninthishistoricalsketch，werelongagoprecededbyDrWellsandMrMatthews。

M。IsidoreGeoffroySaint-Hilaire，inhislecturesdeliveredin1850

(ofwhichaR&eacute。sum&eacute。appearedinthe’RevueetNag。deZoolog。，’

Jan。1851)，brieflygiveshisreasonforbelievingthatspecificcharacterssontfix&eacute。s，pourchaqueesp&egrave。ce，tantqu’elleseperp&eacute。tueaumilieudesm&egrave。mescirconstances：ilssemodifient，silescirconstancesambiantesviennent&agrave。changer。’’Enr&eacute。sum&eacute。，l’observationdesanimauxsauvagesd&eacute。montred&eacute。j&agrave。lavariabilit&eacute。limit&eacute。desesp&egrave。ces。Lesexp&eacute。riencessurlesanimauxsauvagesdevenusdomestiques，etsurlesanimauxdomestiquesredevenussauvages，lad&eacute。montrentplusclairementencore。Cesmemesexp&eacute。riencesprouvent，deplus，quelesdiff&eacute。rencesproduitespeuventetredevaleurg&eacute。n&eacute。rique。’Inhis’Hist。Nat。

G&eacute。n&eacute。ral&eacute。(tom。ii。p。430，1859)heamplifiesanalogousconclusions。

FromacircularlatelyissueditappearsthatDrFreke，in1851(DublinMedicalPress，’p。322)，propoundedthedoctrinethatallorganicbeingshavedescendedfromoneprimordialform。Hisgroundsofbeliefandtreatmentofthesubjectarewhollydifferentfrommine。butasDrFrekehasnow(1861)publishedhisEssayonthe’OriginofSpeciesbymeansofOrganicAffinity，’thedifficultattempttogiveanyideaofhisviewswouldbesuperfluousonmypart。

MrHerbertSpencer，inanEssay(originallypublishedinthe’Leader，’

March，1852，andrepublishedinhis’Essays，’in1858)，hascontrastedthetheoriesoftheCreationandtheDevelopmentoforganicbeingswithremarkableskillandforce。Hearguesfromtheanalogyofdomesticproductions，fromthechangeswhichtheembryosofmanyspeciesundergo，fromthedifficultyofdistinguishingspeciesandvarieties，andfromtheprincipleofgeneralgradation，thatspecieshavebeenmodified。andheattributesthemodificationtothechangeofcircumstances。Theauthor(1855)hasalsotreatedpsychologyontheprincipleofthenecessaryacquirementofeachmentalpowerandcapacitybygradation。

In1852M。Naudin，adistinguishedbotanist，expresslystated，inanadmirablepaperontheOriginofSpecies(’RevueHorticole，p。102。sincepartlyrepublishedinthe’NouvellesArchivesduMus&eacute。um，’tom。i。

p。171)，hisbeliefthatspeciesareformedinananalogousmannerasvarietiesareundercultivation。andthelatterprocessheattributestoman’spowerofselection。Buthedoesnotshowhowselectionactsundernature。Hebelieves，likeDeanHerbert，thatspecies，whennascent，weremoreplasticthanatpresent。Helaysweightonwhathecallstheprincipleoffinality，’puissancemyst&eacute。rieuse，ind&eacute。termin&eacute。e。fatalit&eacute。

pourlesuns。pourlesautresvolont&eacute。providentielle，dontl’actionincessantesurles&egrave。tresvivantsd&eacute。termine，&agrave。toutesles&eacute。poquesdel’existencedumonde，laforme，levolume，etladur&eacute。edechacund’eux，enraisondesadestin&eacute。edansl’ordredechosesdontilfaitpartie。C’estcettepuissancequiharmonisechaquemembre&agrave。l’ensemble，enl’appropriant&agrave。lafonctionqu’ildoitremplirdansl’organismeg&eacute。n&eacute。raldelanature，fonctionquiestpourluisaraisond’&egrave。tre。’*

*FromreferencesinBronn’s’Untersuchungen&uuml。berdieEntwickenlungs-Gesetze，’

itappearsthatthecelebratedbotanistandpalaeontologistUngerpublished，in1852，hisbeliefthatspeciesundergodevelopmentandmodification。

Dalton，likewise，inPanderandDalton’sworkonFossilSloths，expressed，in1821asimilarbelief。Similarviewshave，asiswellknown，beenmaintainedbyOkeninhismystical’Natur-philosophie。’FromotherreferencesinGodron’swork’Surl’Esp&eacute。ce，’itseemsthatBoryStVincent，Burdach，Poiret，andFries，havealladmittedthatnewspeciesarecontinuallybeingproduced。

In1853acelebratedgeologist，CountKeyserling(BulletindelaSoc。

G&egrave。olog。，’2ndSer。，tom。x。p。357)，suggestedthatasnewdiseases，supposedtohavebeencausedbysomemiasma，havearisenandspreadovertheworld，soatcertainperiodsthegermsofexistingspeciesmayhavebeenchemicallyaffectedbycircumambientmoleculesofaparticularnature，andthushavegivenrisetonewforms。

Inthissameyear，1853，DrSchaaffhausenpublishedanexcellentpamphlet(’Verhand。desNaturhist。Vereinsderpreuss。Rheinlands，’&amp。c。)，inwhichhemaintainsthedevelopmentoforganicformsontheearth。Heinfersthatmanyspecieshavekepttrueforlongperiods，whereasafewhavebecomemodified。Thedistinctionofspeciesheexplainsbythedestructionofintermediategraduatedforms。’Thuslivingplantsandanimalsarenotseparatedfromtheextinctbynewcreations，butaretoberegardedastheirdescendantsthroughcontinuedreproduction。’

Imayadd，thatofthethirty-fourauthorsnamedinthisHistoricalSketch，whobelieveinthemodificationofspecies，oratleastdisbelieveinseparateactsofcreation，twenty-sevenhavewrittenonspecialbranchesofnaturalhistoryorgeology。

Awell-knownFrenchbotanist，M。Lecoq，writesin1854(’EtudessurG&eacute。ograph。Bot。，’tom。i。p。250)，’Onvoitquenosrecherchessurlafixit&eacute。oulavariationdel’esp&egrave。ce，nousconduisentdirectementauxid&eacute。es&eacute。mises，pardeuxhommesjustementc&eacute。l&egrave。bres，GeoffroySaint-HilaireetGoethe。’SomeotherpassagesscatteredthroughM。Lecoq’slargework，makeitalittledoubtfulhowfarheextendshisviewsonthemodificationofspecies。

The’PhilosophyofCreation’hasbeentreatedinamasterlymannerbytheRev。BadenPowell，inhisEssaysontheUnityofWorlds，’1855。Nothingcanbemorestrikingthanthemannerinwhichheshowsthattheintroductionofnewspeciesisaregular，notacasualphenomenon，’or，asSirJohnHerschelexpressesit，’anaturalincontradistinctiontoamiraculous，process。’

ThethirdvolumeoftheJournaloftheLinneanSociety’containspapers，readJuly1st，1858，byMrWallaceandmyself，inwhich，asstatedintheintroductoryremarkstothisvolume，thetheoryofNaturalSelectionispromulgatedbyMrWallacewithadmirableforceandclearness。

VonBaer，towardswhomallzoologistsfeelsoprofoundarespect，expressedabouttheyear1859(seeProf。RudolphWagner，aZoologisch-AnthropologischeUntersuchungen，’1861，s。51)hisconviction，chieflygroundedonthelawsofgeographicaldistribution，thatformsnowperfectlydistincthavedescendedfromasingleparent-form。

InJune，1859，ProfessorHuxleygavealecturebeforetheRoyalInstitutiononthe’PersistentTypesofAnimalLife。’Referringtosuchcases，heremarks，Itisdifficulttocomprehendthemeaningofsuchfactsasthese，ifwesupposethateachspeciesofanimalandplant，oreachgreattypeoforganisation，wasformedandplaceduponthesurfaceoftheglobeatlongintervalsbyadistinctactofcreativepower。anditiswelltorecollectthatsuchanassumptionisasunsupportedbytraditionorrevelationasitisopposedtothegeneralanalogyofnature。If，ontheotherhand，weview’PersistentTypes’inrelationtothathypothesiswhichsupposesthespecieslivingatanytimetobetheresultofthegradualmodificationofpre-existingspeciesahypothesiswhich，thoughunproven，andsadlydamagedbysomeofitssupporters，isyettheonlyonetowhichphysiologylendsanycountenance。

theirexistencewouldseemtoshowthattheamountofmodificationwhichlivingbeingshaveundergoneduringgeologicaltimeisbutverysmallinrelationtothewholeseriesofchangeswhichtheyhavesuffered。’

InDecember，1859，DrHookerpublishedhis’IntroductiontotheAustralianFlora。’Inthefirstpartofthisgreatworkheadmitsthetruthofthedescentandmodificationofspecies，andsupportsthisdoctrinebymanyoriginalobservations。

ThefirsteditionofthisworkwaspublishedonNovember24th，1859，andthesecondeditiononJanuary7th，1860。

TheOriginofSpecies-IntroductionTheOriginofSpeciesbyCharlesDarwinIntroductionWHENonboardH。M。S。Beagle，asnaturalist，IwasmuchstruckwithcertainfactsinthedistributionoftheinhabitantsofSouthAmerica，andinthegeologicalrelationsofthepresenttothepastinhabitantsofthatcontinent。

Thesefactsseemedtometothrowsomelightontheoriginofspecies&amp。mdash。

thatmysteryofmysteries，asithasbeencalledbyoneofourgreatestphilosophers。Onmyreturnhome，itoccurredtome，in1837，thatsomethingmightperhapsbemadeoutonthisquestionbypatientlyaccumulatingandreflectingonallsortsoffactswhichcouldpossiblyhaveanybearingonit。Afterfiveyears’workIallowedmyselftospeculateonthesubject，anddrewupsomeshortnotes。theseIenlargedin1844intoasketchoftheconclusions，whichthenseemedtomeprobable：fromthatperiodtothepresentdayIhavesteadilypursuedthesameobject。IhopethatI

maybeexcusedforenteringonthesepersonaldetails，asIgivethemtoshowthatIhavenotbeenhastyincomingtoadecision。

Myworkisnownearlyfinished。butasitwilltakemetwoorthreemoreyearstocompleteit，andasmyhealthisfarfromstrong，IhavebeenurgedtopublishthisAbstract。Ihavemoreespeciallybeeninducedtodothis，asMrWallace，whoisnowstudyingthenaturalhistoryoftheMalayarchipelago，hasarrivedatalmostexactlythesamegeneralconclusionsthatIhaveontheoriginofspecies。Lastyearhesenttomeamemoironthissubject，witharequestthatIwouldforwardittoSirCharlesLyell，whosentittotheLinneanSociety，anditispublishedinthethirdvolumeofthejournalofthatSociety。SirC。LyellandDrHooker，whobothknewofmywork&amp。mdash。thelatterhavingreadmysketchof1844

&amp。mdash。honouredmebythinkingitadvisabletopublish，withMrWallace’sexcellentmemoir，somebriefextractsfrommymanuscripts。

ThisAbstract，whichInowpublish，mustnecessarilybeimperfect。I

cannotheregivereferencesandauthoritiesformyseveralstatements。

andImusttrusttothereaderreposingsomeconfidenceinmyaccuracy。

Nodoubterrorswillhavecreptin，thoughIhopeIhavealwaysbeencautiousintrustingtogoodauthoritiesalone。IcanheregiveonlythegeneralconclusionsatwhichIhavearrived，withafewfactsinillustration，butwhich，Ihope，inmostcaseswillsuffice。NoonecanfeelmoresensiblethanIdoofthenecessityofhereafterpublishingindetailallthefacts，withreferences，onwhichmyconclusionshavebeengrounded。andIhopeinafutureworktodothis。ForIamwellawarethatscarcelyasinglepointisdiscussedinthisvolumeonwhichfactscannotbeadduced，oftenapparentlyleadingtoconclusionsdirectlyoppositetothoseatwhichI

havearrived。Afairresultcanbeobtainedonlybyfullystatingandbalancingthefactsandargumentsonbothsidesofeachquestion。andthiscannotpossiblybeheredone。

ImuchregretthatwantofspacepreventsmyhavingthesatisfactionofacknowledgingthegenerousassistancewhichIhavereceivedfromverymanynaturalists，someofthempersonallyunknowntome。Icannot，however，letthisopportunitypasswithoutexpressingmydeepobligationstoDrHooker，whoforthelastfifteenyearshasaidedmeineverypossiblewaybyhislargestoresofknowledgeandhisexcellentjudgement。

InconsideringtheOriginofSpecies，itisquiteconceivablethatanaturalist，reflectingonthemutualaffinitiesoforganicbeings，ontheirembryologicalrelations，theirgeographicaldistribution，geologicalsuccession，andothersuchfacts，mightcometotheconclusionthateachspecieshadnotbeenindependentlycreated，buthaddescended，likevarieties，fromotherspecies。Nevertheless，suchaconclusion，evenifwellfounded，wouldbeunsatisfactory，untilitcouldbeshownhowtheinnumerablespeciesinhabitingthisworldhavebeenmodifiedsoastoacquirethatperfectionofstructureandco-adaptationwhichmostjustlyexcitesouradmiration。

Naturalistscontinuallyrefertoexternalconditions，suchasclimate，food，&amp。c。，astheonlypossiblecauseofvariation。Inoneverylimitedsense，asweshallhereaftersee，thismaybetrue。butitispreposteroustoattributetomereexternalconditions，thestructure，forinstance，ofthewoodpecker，withitsfeet，tail，beak，andtongue，soadmirablyadaptedtocatchinsectsunderthebarkoftrees。Inthecaseofthemisseltoe，whichdrawsitsnourishmentfromcertaintrees，whichhasseedsthatmustbetransportedbycertainbirds，andwhichhasflowerswithseparatesexesabsolutelyrequiringtheagencyofcertaininsectstobringpollenfromoneflowertotheother，itisequallypreposteroustoaccountforthestructureofthisparasite，withitsrelationstoseveraldistinctorganicbeings，bytheeffectsofexternalconditions，orofhabit，orofthevolitionoftheplantitself。

Theauthorofthe’VestigesofCreation’would，Ipresume，saythat，afteracertainunknownnumberofgenerations，somebirdhadgivenbirthtoawoodpecker，andsomeplanttothemisseltoe，andthatthesehadbeenproducedperfectaswenowseethem。butthisassumptionseemstometobenoexplanation，foritleavesthecaseofthecoadaptationsoforganicbeingstoeachotherandtotheirphysicalconditionsoflife，untouchedandunexplained。

Itis，therefore，ofthehighestimportancetogainaclearinsightintothemeansofmodificationandcoadaptation。Atthecommencementofmyobservationsitseemedtomeprobablethatacarefulstudyofdomesticatedanimalsandofcultivatedplantswouldofferthebestchanceofmakingoutthisobscureproblem。NorhaveIbeendisappointed。inthisandinallotherperplexingcasesIhaveinvariablyfoundthatourknowledge，imperfectthoughitbe，ofvariationunderdomestication，affordedthebestandsafestclue。Imayventuretoexpressmyconvictionofthehighvalueofsuchstudies，althoughtheyhavebeenverycommonlyneglectedbynaturalists。

Fromtheseconsiderations，IshalldevotethefirstchapterofthisAbstracttoVariationunderDomestication。Weshallthusseethatalargeamountofhereditarymodificationisatleastpossible，and，whatisequallyormoreimportant，weshallseehowgreatisthepowerofmaninaccumulatingbyhisSelectionsuccessiveslightvariations。Iwillthenpassontothevariabilityofspeciesinastateofnature。butIshall，unfortunately，becompelledtotreatthissubjectfartoobriefly，asitcanbetreatedproperlyonlybygivinglongcataloguesoffacts。Weshall，however，beenabledtodiscusswhatcircumstancesaremostfavourabletovariation。

InthenextchaptertheStruggleforExistenceamongstallorganicbeingsthroughouttheworld，whichinevitablyfollowsfromtheirhighgeometricalpowersofincrease，willbetreatedof。ThisisthedoctrineofMalthus，appliedtothewholeanimalandvegetablekingdoms。Asmanymoreindividualsofeachspeciesarebornthancanpossiblysurvive。andas，consequently，thereisafrequentlyrecurringstruggleforexistence，itfollowsthatanybeing，ifitvaryhoweverslightlyinanymannerprofitabletoitself，underthecomplexandsometimesvaryingconditionsoflife，willhaveabetterchanceofsurviving，andthusbenaturallyselected。Fromthestrongprincipleofinheritance，anyselectedvarietywilltendtopropagateitsnewandmodifiedform。

ThisfundamentalsubjectofNaturalSelectionwillbetreatedatsomelengthinthefourthchapter。andweshallthenseehowNaturalSelectionalmostinevitablycausesmuchExtinctionofthelessimprovedformsoflifeandinduceswhatIhavecalledDivergenceofCharacter。InthenextchapterIshalldiscussthecomplexandlittleknownlawsofvariationandofcorrelationofgrowth。Inthefoursucceedingchapters，themostapparentandgravestdifficultiesonthetheorywillbegiven：namely，first，thedifficultiesoftransitions，orunderstandinghowasimplebeingorasimpleorgancanbechangedandperfectedintoahighlydevelopedbeingorelaboratelyconstructedorgan。secondlythesubjectofInstinct，orthementalpowersofanimals，thirdly，Hybridism，ortheinfertilityofspeciesandthefertilityofvarietieswhenintercrossed。andfourthly，theimperfectionoftheGeologicalRecord。InthenextchapterIshallconsiderthegeologicalsuccessionoforganicbeingsthroughouttime。intheeleventhandtwelfth，theirgeographicaldistributionthroughoutspace。

inthethirteenth，theirclassificationormutualaffinities，bothwhenmatureandinanembryoniccondition。InthelastchapterIshallgiveabriefrecapitulationofthewholework，andafewconcludingremarks。)

Nooneoughttofeelsurpriseatmuchremainingasyetunexplainedinregardtotheoriginofspeciesandvarieties，ifhemakesdueallowanceforourprofoundignoranceinregardtothemutualrelationsofallthebeingswhichlivearoundus。Whocanexplainwhyonespeciesrangeswidelyandisverynumerous，andwhyanotheralliedspecieshasanarrowrangeandisrare？Yettheserelationsareofthehighestimportance，fortheydeterminethepresentwelfare，and，asIbelieve，thefuturesuccessandmodificationofeveryinhabitantofthisworld。Stilllessdoweknowofthemutualrelationsoftheinnumerableinhabitantsoftheworldduringthemanypastgeologicalepochsinitshistory。Althoughmuchremainsobscure，andwilllongremainobscure，Icanentertainnodoubt，afterthemostdeliberatestudyanddispassionatejudgementofwhichIamcapable，thattheviewwhichmostnaturalistsentertain，andwhichIformerlyentertained&amp。mdash。namely，thateachspecieshasbeenindependentlycreated&amp。mdash。

iserroneous。Iamfullyconvincedthatspeciesarenotimmutable。butthatthosebelongingtowhatarecalledthesamegeneraarelinealdescendantsofsomeotherandgenerallyextinctspecies，inthesamemannerastheacknowledgedvarietiesofanyonespeciesarethedescendantsofthatspecies。

Furthermore，IamconvincedthatNaturalSelectionhasbeenthemainbutnotexclusivemeansofmodification。

TheOriginofSpecies-Chapter1TheOriginofSpeciesbyCharlesDarwinNextChapterChapter1-VariationUnderDomesticationWHENwelooktotheindividualsofthesamevarietyorsub-varietyofouroldercultivatedplantsandanimals，oneofthefirstpointswhichstrikesus，is，thattheygenerallydiffermuchmorefromeachother，thandotheindividualsofanyonespeciesorvarietyinastateofnature。

Whenwereflectonthevastdiversityoftheplantsandanimalswhichhavebeencultivated，andwhichhavevariedduringallagesunderthemostdifferentclimatesandtreatment，Ithinkwearedriventoconcludethatthisgreatervariabilityissimplyduetoourdomesticproductionshavingbeenraisedunderconditionsoflifenotsouniformas，andsomewhatdifferentfrom，thosetowhichtheparent-specieshavebeenexposedundernature。Thereis，also，Ithink，someprobabilityintheviewpropoundedbyAndrewKnight，thatthisvariabilitymaybepartlyconnectedwithexcessoffood。Itseemsprettyclearthatorganicbeingsmustbeexposedduringseveralgenerationstothenewconditionsoflifetocauseanyappreciableamountofvariation。

andthatwhentheorganisationhasoncebeguntovary，itgenerallycontinuestovaryformanygenerations。Nocaseisonrecordofavariablebeingceasingtobevariableundercultivation。Ouroldestcultivatedplants，suchaswheat，stilloftenyieldnewvarieties：ouroldestdomesticatedanimalsarestillcapableofrapidimprovementormodification。

Ithasbeendisputedatwhatperiodoftimethecausesofvariability，whatevertheymaybe，generallyact。whetherduringtheearlyorlateperiodofdevelopmentoftheembryo，orattheinstantofconception。GeoffroyStHilaire’sexperimentsshowthatunnaturaltreatmentoftheembryocausesmonstrosities。andmonstrositiescannotbeseparatedbyanyclearlineofdistinctionfrommerevariations。ButIamstronglyinclinedtosuspectthatthemostfrequentcauseofvariabilitymaybeattributedtothemaleandfemalereproductiveelementshavingbeenaffectedpriortotheactofconception。Severalreasonsmakemebelieveinthis。butthechiefoneistheremarkableeffectwhichconfinementorcultivationhasonthefunctionsofthereproductivesystem。thissystemappearingtobefarmoresusceptiblethananyotherpartoftheorganization，totheactionofanychangeintheconditionsoflife。Nothingismoreeasythantotameananimal，andfewthingsmoredifficultthantogetittobreedfreelyunderconfinement，eveninthemanycaseswhenthemaleandfemaleunite。Howmanyanimalstherearewhichwillnotbreed，thoughlivinglongundernotverycloseconfinementintheirnativecountry！Thisisgenerallyattributedtovitiatedinstincts。buthowmanycultivatedplantsdisplaytheutmostvigour，andyetrarelyorneverseed！Insomefewsuchcasesithasbeenfoundoutthatverytriflingchanges，suchasalittlemoreorlesswateratsomeparticularperiodofgrowth，willdeterminewhetherornottheplantsetsaseed。IcannothereenteronthecopiousdetailswhichIhavecollectedonthiscurioussubject。buttoshowhowsingularthelawsarewhichdeterminethereproductionofanimalsunderconfinement，Imayjustmentionthatcarnivorousanimals，evenfromthetropics，breedinthiscountryprettyfreelyunderconfinement，withtheexceptionoftheplantigradesorbearfamily。whereas，carnivorousbirds，withtherarestexceptions，hardlyeverlayfertileeggs。Manyexoticplantshavepollenutterlyworthless，inthesameexactconditionasinthemoststerilehybrids。When，ontheonehand，weseedomesticatedanimalsandplants，thoughoftenweakandsickly，yetbreedingquitefreelyunderconfinement。andwhen，ontheotherhand，weseeindividuals，thoughtakenyoungfromastateofnature，perfectlytamed，long-lived，andhealthy(ofwhichIcouldgivenumerousinstances)，yethavingtheirreproductivesystemsoseriouslyaffectedbyunperceivedcausesastofailinacting，weneednotbesurprisedatthissystem，whenitdoesactunderconfinement，actingnotquiteregularly，andproducingoffspringnotperfectlyliketheirparentsorvariable。

Sterilityhasbeensaidtobethebaneofhorticulture。butonthisviewweowevariabilitytothesamecausewhichproducessterility。andvariabilityisthesourceofallthechoicestproductionsofthegarden。

Imayadd，thatassomeorganismswillbreedmostfreelyunderthemostunnaturalconditions(forinstance，therabbitandferretkeptinhutches)，showingthattheirreproductivesystemhasnotbeenthusaffected。sowillsomeanimalsandplantswithstanddomesticationorcultivation，andvaryveryslightlyperhapshardlymorethaninastateofnature。

Alonglistcouldeasilybegivenof’sportingplants。’bythistermgardenersmeanasinglebudoroffset，whichsuddenlyassumesanewandsometimesverydifferentcharacterfromthatoftherestoftheplant。

Suchbudscanbepropagatedbygrafting，&amp。c。，andsometimesbyseed。

These’sports’areextremelyrareundernature，butfarfromrareundercultivation。andinthiscaseweseethatthetreatmentoftheparenthasaffectedabudoroffset，andnottheovulesorpollen。Butitistheopinionofmostphysiologiststhatthereisnoessentialdifferencebetweenabudandanovuleintheirearlieststagesofformation。sothat，infact，’sports’

supportmyview，thatvariabilitymaybelargelyattributedtotheovulesorpollen，ortoboth，havingbeenaffectedbythetreatmentoftheparentpriortotheactofconception。Thesecasesanyhowshowthatvariationisnotnecessarilyconnected，assomeauthorshavesupposed，withtheactofgeneration。

Seedlingsfromthesamefruit，andtheyoungofthesamelitter，sometimesdifferconsiderablyfromeachother，thoughboththeyoungandtheparents，asMullerhasremarked，haveapparentlybeenexposedtoexactlythesameconditionsoflife。andthisshowshowunimportantthedirecteffectsoftheconditionsoflifeareincomparisonwiththelawsofreproduction，andofgrowth，andofinheritance。forhadtheactionoftheconditionsbeendirect，ifanyoftheyounghadvaried，allwouldprobablyhavevariedinthesamemanner。Tojudgehowmuch，inthecaseofanyvariation，weshouldattributetothedirectactionofheat，moisture，light，food，&amp。c。，ismostdifficult：myimpressionis，thatwithanimalssuchagencieshaveproducedverylittledirecteffect，thoughapparentlymoreinthecaseofplants。Underthispointofview，MrBuckman’srecentexperimentsonplantsseemextremelyvaluable。Whenallornearlyalltheindividualsexposedtocertainconditionsareaffectedinthesameway，thechangeatfirstappearstobedirectlyduetosuchconditions。butinsomecasesitcanbeshownthatquiteoppositeconditionsproducesimilarchangesofstructure。Neverthelesssomeslightamountofchangemay，Ithink，beattributedtothedirectactionoftheconditionsoflifeas，insomecases，increasedsizefromamountoffood，colourfromparticularkindsoffoodandfromlight，andperhapsthethicknessoffurfromclimate。

Habitalsohasadecidinginfluence，asintheperiodoffloweringwithplantswhentransportedfromoneclimatetoanother。Inanimalsithasamoremarkedeffect。forinstance，Ifindinthedomesticduckthatthebonesofthewingweighlessandthebonesofthelegmore，inproportiontothewholeskeleton，thandothesamebonesinthewild-duck。andIpresumethatthischangemaybesafelyattributedtothedomesticduckflyingmuchless，andwalkingmore，thanitswildparent。Thegreatandinheriteddevelopmentoftheuddersincowsandgoatsincountrieswheretheyarehabituallymilked，incomparisonwiththestateoftheseorgansinothercountries，isanotherinstanceoftheeffectofuse。Notasingledomesticanimalcanbenamedwhichhasnotinsomecountrydroopingears。andtheviewsuggestedbysomeauthors，thatthedroopingisduetothedisuseofthemusclesoftheear，fromtheanimalsnotbeingmuchalarmedbydanger，seemsprobable。

Therearemanylawsregulatingvariation，somefewofwhichcanbedimlyseen，andwillbehereafterbrieflymentioned。Iwillhereonlyalludetowhatmaybecalledcorrelationofgrowth。Anychangeintheembryoorlarvawillalmostcertainlyentailchangesinthematureanimal。Inmonstrosities，thecorrelationsbetweenquitedistinctpartsareverycurious。andmanyinstancesaregiveninIsidoreGeoffroyStHilaire’sgreatworkonthissubject。Breedersbelievethatlonglimbsarealmostalwaysaccompaniedbyanelongatedhead。Someinstancesofcorrelationarequitewhimsical。

thuscatswithblueeyesareinvariablydeaf。colourandconstitutionalpeculiaritiesgotogether，ofwhichmanyremarkablecasescouldbegivenamongstanimalsandplants。FromthefactscollectedbyHeusinger，itappearsthatwhitesheepandpigsaredifferentlyaffectedfromcolouredindividualsbycertainvegetablepoisons。Hairlessdogshaveimperfectteeth。long-hairedandcoarse-hairedanimalsareapttohave，asisasserted，longormanyhorns。pigeonswithfeatheredfeethaveskinbetweentheiroutertoes。

pigeonswithshortbeakshavesmallfeet，andthosewithlongbeakslargefeet。Hence，ifmangoesonselecting，andthusaugmenting，anypeculiarity，hewillalmostcertainlyunconsciouslymodifyotherpartsofthestructure，owingtothemysteriouslawsofthecorrelationofgrowth。

Theresultofthevarious，quiteunknown，ordimlyseenlawsofvariationisinfinitelycomplexanddiversified。Itiswellworthwhilecarefullytostudytheseveraltreatisespublishedonsomeofouroldcultivatedplants，asonthehyacinth，potato，eventhedahlia，&amp。c……anditisreallysurprisingtonotetheendlesspointsinstructureandconstitutioninwhichthevarietiesandsubvarietiesdifferslightlyfromeachother。

Thewholeorganizationseemstohavebecomeplastic，andtendstodepartinsomesmalldegreefromthatoftheparentaltype。

Anyvariationwhichisnotinheritedisunimportantforus。Butthenumberanddiversityofinheritabledeviationsofstructure，boththoseofslightandthoseofconsiderablephysiologicalimportance，isendless。

DrProsperLucas’streatise，intwolargevolumes，isthefullestandthebestonthissubject。Nobreederdoubtshowstrongisthetendencytoinheritance：

likeproduceslikeishisfundamentalbelief：doubtshavebeenthrownonthisprinciplebytheoreticalwritersalone。Whenadeviationappearsnotunfrequently，andweseeitinthefatherandchild，wecannottellwhetheritmaynotbeduetothesameoriginalcauseactingonboth。butwhenamongstindividuals，apparentlyexposedtothesameconditions，anyveryraredeviation，duetosomeextraordinarycombinationofcircumstances，appearsintheparentsay，onceamongstseveralmillionindividualsanditreappearsinthechild，themeredoctrineofchancesalmostcompelsustoattributeitsreappearancetoinheritance。Everyonemusthaveheardofcasesofalbinism，pricklyskin，hairybodies，&amp。c。appearinginseveralmembersofthesamefamily。Ifstrangeandraredeviationsofstructurearetrulyinherited，lessstrangeandcommonerdeviationsmaybefreelyadmittedtobeinheritable。Perhapsthecorrectwayofviewingthewholesubject，wouldbe，tolookattheinheritanceofeverycharacterwhateverastherule，andnon-inheritanceastheanomaly。

Thelawsgoverninginheritancearequiteunknown。noonecansaywhythesamepeculiarityindifferentindividualsofthesamespecies，andinindividualsofdifferentspecies，issometimesinheritedandsometimesnotso。whythechildoftenrevertsincertaincharacterstoitsgrandfatherorgrandmotherorothermuchmoreremoteancestor。whyapeculiarityisoftentransmittedfromonesextobothsexesortoonesexalone，morecommonlybutnotexclusivelytothelikesex。Itisafactofsomelittleimportancetous，thatpeculiaritiesappearinginthemalesofourdomesticbreedsareoftentransmittedeitherexclusively，orinamuchgreaterdegree，tomalesalone。Amuchmoreimportantrule，whichIthinkmaybetrusted，isthat，atwhateverperiodoflifeapeculiarityfirstappears，ittendstoappearintheoffspringatacorrespondingage，thoughsometimesearlier。

Inmanycasesthiscouldnotbeotherwise：thustheinheritedpeculiaritiesinthehornsofcattlecouldappearonlyintheoffspringwhennearlymature。

peculiaritiesinthesilkwormareknowntoappearatthecorrespondingcaterpillarorcocoonstage。Buthereditarydiseasesandsomeotherfactsmakemebelievethattherulehasawiderextension，andthatwhenthereisnoapparentreasonwhyapeculiarityshouldappearatanyparticularage，yetthatitdoestendtoappearintheoffspringatthesameperiodatwhichitfirstappearedintheparent。Ibelievethisruletobeofthehighestimportanceinexplainingthelawsofembryology。Theseremarksareofcourseconfinedtothefirstappearanceofthepeculiarity，andnottoitsprimarycause，whichmayhaveactedontheovulesormaleelement。innearlythesamemannerasinthecrossedoffspringfromashort-hornedcowbyalong-hornedbull，thegreaterlengthofhorn，thoughappearinglateinlife，isclearlyduetothemaleelement。

Havingalludedtothesubjectofreversion，Imayhererefertoastatementoftenmadebynaturalistsnamely，thatourdomesticvarieties，whenrunwild，graduallybutcertainlyrevertincharactertotheiraboriginalstocks。

Henceithasbeenarguedthatnodeductionscanbedrawnfromdomesticracestospeciesinastateofnature。Ihaveinvainendeavouredtodiscoveronwhatdecisivefactstheabovestatementhassooftenandsoboldlybeenmade。Therewouldbegreatdifficultyinprovingitstruth：wemaysafelyconcludethatverymanyofthemoststrongly-markeddomesticvarietiescouldnotpossiblyliveinawildstate。Inmanycaseswedonotknowwhattheaboriginalstockwas，andsocouldnottellwhetherornotnearlyperfectreversionhadensued。Itwouldbequitenecessary，inordertopreventtheeffectsofintercrossing，thatonlyasinglevarietyshouldbeturnedlooseinitsnewhome。Nevertheless，asourvarietiescertainlydooccasionallyrevertinsomeoftheircharacterstoancestralforms，itseemstomenotimprobable，thatifwecouldsucceedinnaturalising，orweretocultivate，duringmanygenerations，theseveralraces，forinstance，ofthecabbage，inverypoorsoil(inwhichcase，however，someeffectwouldhavetobeattributedtothedirectactionofthepoorsoil)，thattheywouldtoalargeextent，orevenwholly，reverttothewildaboriginalstock。Whetherornottheexperimentwouldsucceed，isnotofgreatimportanceforourlineofargument。forbytheexperimentitselftheconditionsoflifearechanged。Ifitcouldbeshownthatourdomesticvarietiesmanifestedastrongtendencytoreversion，thatis，tolosetheiracquiredcharacters，whilstkeptunderunchangedconditions，andwhilstkeptinaconsiderablebody，sothatfreeintercrossingmightcheck，byblendingtogether，anyslightdeviationsofstructure，insuchcase，Igrantthatwecoulddeducenothingfromdomesticvarietiesinregardtospecies。Butthereisnotashadowofevidenceinfavourofthisview：toassertthatwecouldnotbreedourcartandrace-horses，longandshort-hornedcattleandpoultryofvariousbreeds，andesculentvegetables，foranalmostinfinitenumberofgenerations，wouldbeopposedtoallexperience。Imayadd，thatwhenundernaturetheconditionsoflifedochange，variationsandreversionsofcharacterprobablydooccur。butnaturalselection，aswillhereafterbeexplained，willdeterminehowfarthenewcharactersthusarisingshallbepreserved。

Whenwelooktothehereditaryvarietiesorracesofourdomesticanimalsandplants，andcomparethemwithspeciescloselyalliedtogether，wegenerallyperceiveineachdomesticrace，asalreadyremarked，lessuniformityofcharacterthanintruespecies。Domesticracesofthesamespecies，also，oftenhaveasomewhatmonstrouscharacter。bywhichImean，that，althoughdifferingfromeachother，andfromtheotherspeciesofthesamegenus，inseveraltriflingrespects，theyoftendifferinanextremedegreeinsomeonepart，bothwhencomparedonewithanother，andmoreespeciallywhencomparedwithallthespeciesinnaturetowhichtheyarenearestallied。Withtheseexceptions(andwiththatoftheperfectfertilityofvarietieswhencrossed，asubjecthereaftertobediscussed)，domesticracesofthesamespeciesdifferfromeachotherinthesamemanneras，onlyinmostcasesinalesserdegreethan，doclosely-alliedspeciesofthesamegenusinastateofnature。Ithinkthismustbeadmitted，whenwefindthattherearehardlyanydomesticraces，eitheramongstanimalsorplants，whichhavenotbeenrankedbysomecompetentjudgesasmerevarieties，andbyothercompetentjudgesasthedescendantsofaboriginallydistinctspecies。Ifanymarkeddistinctionexistedbetweendomesticracesandspecies，thissourceofdoubtcouldnotsoperpetuallyrecur。Ithasoftenbeenstatedthatdomesticracesdonotdifferfromeachotherincharactersofgenericvalue。Ithinkitcouldbeshownthatthisstatementishardlycorrect。butnaturalistsdiffermostwidelyindeterminingwhatcharactersareofgenericvalue。allsuchvaluationsbeingatpresentempirical。

Moreover，ontheviewoftheoriginofgenerawhichIshallpresentlygive，wehavenorighttoexpectoftentomeetwithgenericdifferencesinourdomesticatedproductions。

Whenweattempttoestimatetheamountofstructuraldifferencebetweenthedomesticracesofthesamespecies，wearesooninvolvedindoubt，fromnotknowingwhethertheyhavedescendedfromoneorseveralparent-species。

Thispoint，ifcouldbeclearedup，wouldbeinteresting。if，forinstance，itcouldbeshownthatthegreyhound，bloodhound，terrier，spaniel，andbull-dog，whichweallknowpropagatetheirkindsotruly，weretheoffspringofanysinglespecies，thensuchfactswouldhavegreatweightinmakingusdoubtabouttheimmutabilityofthemanyverycloselyalliedandnaturalspeciesforinstance，ofthemanyfoxesinhabitingdifferentquartersoftheworld。Idonotbelieve，asweshallpresentlysee，thatallourdogshavedescendedfromanyonewildspecies。but，inthecaseofsomeotherdomesticraces，thereispresumptive，orevenstrong，evidenceinfavourofthisview。

Ithasoftenbeenassumedthatmanhaschosenfordomesticationanimalsandplantshavinganextraordinaryinherenttendencytovary，andlikewisetowithstanddiverseclimates。Idonotdisputethatthesecapacitieshaveaddedlargelytothevalueofmostofourdomesticatedproductions。buthowcouldasavagepossiblyknow，whenhefirsttamedananimal，whetheritwouldvaryinsucceedinggenerations，andwhetheritwouldendureotherclimates？Hasthelittlevariabilityoftheassorguinea-fowl，orthesmallpowerofenduranceofwarmthbythereindeer，orofcoldbythecommoncamel，preventedtheirdomestication？Icannotdoubtthatifotheranimalsandplants，equalinnumbertoourdomesticatedproductions，andbelongingtoequallydiverseclassesandcountries，weretakenfromastateofnature，andcouldbemadetobreedforanequalnumberofgenerationsunderdomestication，theywouldvaryonanaverageaslargelyastheparentspeciesofourexistingdomesticatedproductionshavevaried。

Inthecaseofmostofourancientlydomesticatedanimalsandplants，Idonotthinkitispossibletocometoanydefiniteconclusion，whethertheyhavedescendedfromoneorseveralspecies。Theargumentmainlyreliedonbythosewhobelieveinthemultipleoriginofourdomesticanimalsis，thatwefindinthemostancientrecords，moreespeciallyonthemonumentsofEgypt，muchdiversityinthebreeds。andthatsomeofthebreedscloselyresemble，perhapsareidenticalwith，thosestillexisting。Evenifthislatterfactwerefoundmorestrictlyandgenerallytruethanseemstometobethecase，whatdoesitshow，butthatsomeofourbreedsoriginatedthere，fourorfivethousandyearsago？ButMrHorner’sresearcheshaverendereditinsomedegreeprobablethatmansufficientlycivilizedtohavemanufacturedpotteryexistedinthevalleyoftheNilethirteenorfourteenthousandyearsago。andwhowillpretendtosayhowlongbeforetheseancientperiods，savages，likethoseofTierradelFuegoorAustralia，whopossessasemi-domesticdog，maynothaveexistedinEgypt？

Thewholesubjectmust，Ithink，remainvague。nevertheless，Imay，withouthereenteringonanydetails，statethat，fromgeographicalandotherconsiderations，Ithinkithighlyprobablethatourdomesticdogshavedescendedfromseveralwildspecies。InregardtosheepandgoatsIcanformnoopinion。Ishouldthink，fromfactscommunicatedtomebyMrBlyth，onthehabits，voice，andconstitution，&amp。c。，ofthehumpedIndiancattle，thatthesehaddescendedfromadifferentaboriginalstockfromourEuropeancattle。andseveralcompetentjudgesbelievethattheselatterhavehadmorethanonewildparent。Withrespecttohorses，fromreasonswhichIcannotgivehere，Iamdoubtfullyinclinedtobelieve，inoppositiontoseveralauthors，thatalltheraceshavedescendedfromonewildstock。MrBlyth，whoseopinion，fromhislargeandvariedstoresofknowledge，Ishouldvaluemorethanthatofalmostanyone，thinksthatallthebreedsofpoultryhaveproceededfromthecommonwildIndianfowl(Gallusbankiva)。Inregardtoducksandrabbits，thebreedsofwhichdifferconsiderablyfromeachotherinstructure，Idonotdoubtthattheyallhavedescendedfromthecommonwildduckandrabbit。

Thedoctrineoftheoriginofourseveraldomesticracesfromseveralaboriginalstocks，hasbeencarriedtoanabsurdextremebysomeauthors。

Theybelievethateveryracewhichbreedstrue，letthedistinctivecharactersbeeversoslight，hashaditswildprototype。Atthisratetheremusthaveexistedatleastascoreofspeciesofwildcattle，asmanysheep，andseveralgoatsinEuropealone，andseveralevenwithinGreatBritain。

OneauthorbelievesthatthereformerlyexistedinGreatBritainelevenwildspeciesofsheeppeculiartoit！WhenwebearinmindthatBritainhasnowhardlyonepeculiarmammal，andFrancebutfewdistinctfromthoseofGermanyandconversely，andsowithHungary，Spain，&amp。c。，butthateachofthesekingdomspossessesseveralpeculiarbreedsofcattle，sheep，&amp。c。，wemustadmitthatmanydomesticbreedshaveoriginatedinEurope。

forwhencecouldtheyhavebeenderived，astheseseveralcountriesdonotpossessanumberofpeculiarspeciesasdistinctparent-stocks？SoitisinIndia。Eveninthecaseofthedomesticdogsofthewholeworld，whichIfullyadmithaveprobablydescendedfromseveralwildspecies，Icannotdoubtthattherehasbeenanimmenseamountofinheritedvariation。

WhocanbelievethatanimalscloselyresemblingtheItaliangreyhound，thebloodhound，thebull-dog，orBlenheimspaniel，&amp。c。sounlikeallwildCanidaeeverexistedfreelyinastateofnature？Ithasoftenbeenlooselysaidthatallourracesofdogshavebeenproducedbythecrossingofafewaboriginalspecies。butbycrossingwecangetonlyformsinsomedegreeintermediatebetweentheirparents。andifweaccountforourseveraldomesticracesbythisprocess，wemustadmittheformerexistenceofthemostextremeforms，astheItaliangreyhound，bloodhound，bull-dog，&amp。c。，inthewildstate。Moreover，thepossibilityofmakingdistinctracesbycrossinghasbeengreatlyexaggerated。Therecanbenodoubtthataracemaybemodifiedbyoccasionalcrosses，ifaidedbythecarefulselectionofthoseindividualmongrels，whichpresentanydesiredcharacter。butthataracecouldbeobtainednearlyintermediatebetweentwoextremelydifferentracesorspecies，Icanhardlybelieve。SirJ。Sebrightexpresslyexperimentisedforthisobject，andfailed。Theoffspringfromthefirstcrossbetweentwopurebreedsistolerablyandsometimes(asIhavefoundwithpigeons)extremelyuniform，andeverythingseemssimpleenough。butwhenthesemongrelsarecrossedonewithanotherforseveralgenerations，hardlytwoofthemwillbealike，andthentheextremedifficulty，orratherutterhopelessness，ofthetaskbecomesapparent。Certainly，abreedintermediatebetweentwoverydistinctbreedscouldnotbegotwithoutextremecareandlong-continuedselection。norcanIfindasinglecaseonrecordofapermanentracehavingbeenthusformed。OntheBreedsoftheDomesticpigeon。Believingthatitisalwaysbesttostudysomespecialgroup，Ihave，afterdeliberation，takenupdomesticpigeons。IhavekepteverybreedwhichIcouldpurchaseorobtain，andhavebeenmostkindlyfavouredwithskinsfromseveralquartersoftheworld，moreespeciallybytheHon。W。ElliotfromIndia，andbytheHon。C。MurrayfromPersia。Manytreatisesindifferentlanguageshavebeenpublishedonpigeons，andsomeofthemareveryimportant，asbeingofconsiderablyantiquity。Ihaveassociatedwithseveraleminentfanciers，andhavebeenpermittedtojointwooftheLondonPigeonClubs。

Thediversityofthebreedsissomethingastonishing。ComparetheEnglishcarrierandtheshort-facedtumbler，andseethewonderfuldifferenceintheirbeaks，entailingcorrespondingdifferencesintheirskulls。Thecarrier，moreespeciallythemalebird，isalsoremarkablefromthewonderfuldevelopmentofthecarunculatedskinaboutthehead，andthisisaccompaniedbygreatlyelongatedeyelids，verylargeexternalorificestothenostrils，andawidegapeofmouth。Theshort-facedtumblerhasabeakinoutlinealmostlikethatofafinch。andthecommontumblerhasthesingularandstrictlyinheritedhabitofflyingatagreatheightinacompactflock，andtumblingintheairheadoverheels。Theruntisabirdofgreatsize，withlong，massivebeakandlargefeet。someofthesub-breedsofruntshaveverylongnecks，othersverylongwingsandtails，otherssingularlyshorttails。

Thebarbisalliedtothecarrier，but，insteadofaverylongbeak，hasaveryshortandverybroadone。Thepouterhasamuchelongatedbody，wings，andlegs。anditsenormouslydevelopedcrop，whichitgloriesininflating，maywellexciteastonishmentandevenlaughter。Theturbithasaveryshortandconicalbeak，withalineofreversedfeathersdownthebreast。andithasthehabitofcontinuallyexpandingslightlytheupperpartoftheoesophagus。TheJacobinhasthefeatherssomuchreversedalongthebackoftheneckthattheyformahood，andithas，proportionallytoitssize，muchelongatedwingandtailfeathers。Thetrumpeterandlaugher，astheirnamesexpress，utteraverydifferentcoofromtheotherbreeds。

Thefantailhasthirtyorevenfortytail-feathers，insteadoftwelveorfourteen，thenormalnumberinallmembersofthegreatpigeonfamily。

andthesefeathersarekeptexpanded，andarecarriedsoerectthatingoodbirdstheheadandtailtouch。theoil-glandisquiteaborted。Severalotherlessdistinctbreedsmighthavebeenspecified。

Intheskeletonsoftheseveralbreeds，thedevelopmentofthebonesofthefaceinlengthandbreadthandcurvaturediffersenormously。Theshape，aswellasthebreadthandlengthoftheramusofthelowerjaw，variesinahighlyremarkablemanner。Thenumberofthecaudalandsacralvertebraevary。asdoesthenumberoftheribs，togetherwiththeirrelativebreadthandthepresenceofprocesses。Thesizeandshapeoftheaperturesinthesternumarehighlyvariable。soisthedegreeofdivergenceandrelativesizeofthetwoarmsofthefurcula。Theproportionalwidthofthegapeofmouth，theproportionallengthoftheeyelids，oftheorificeofthenostrils，ofthetongue(notalwaysinstrictcorrelationwiththelengthofbeak)，thesizeofthecropandoftheupperpartoftheoesophagus。

thedevelopmentandabortionoftheoil-gland。thenumberoftheprimarywingandcaudalfeathers。therelativelengthofwingandtailtoeachotherandtothebody。therelativelengthoflegandofthefeet。thenumberofscutellaeonthetoes，thedevelopmentofskinbetweenthetoes，areallpointsofstructurewhicharevariable。Theperiodatwhichtheperfectplumageisacquiredvaries，asdoesthestateofthedownwithwhichthenestlingbirdsareclothedwhenhatched。Theshapeandsizeoftheeggsvary。Themannerofflightdiffersremarkably。asdoesinsomebreedsthevoiceanddisposition。Lastly，incertainbreeds，themalesandfemaleshavecometodiffertoaslightdegreefromeachother。

Altogetheratleastascoreofpigeonsmightbechosen，whichifshowntoanornithologist，andheweretoldthattheywerewildbirds，wouldcertainly，Ithink，berankedbyhimaswell-definedspecies。Moreover，IdonotbelievethatanyornithologistwouldplacetheEnglishcarrier，theshort-facedtumbler，therunt，thebarb，pouter，andfantailinthesamegenus。moreespeciallyasineachofthesebreedsseveraltruly-inheritedsub-breeds，orspeciesashemighthavecalledthem，couldbeshownhim。

Greatasthedifferencesarebetweenthebreedsofpigeons，Iamfullyconvincedthatthecommonopinionofnaturalistsiscorrect，namely，thatallhavedescendedfromtherock-pigeon(Columbalivia)，includingunderthistermseveralgeographicalracesorsub-species，whichdifferfromeachotherinthemosttriflingrespects。Asseveralofthereasonswhichhaveledmetothisbeliefareinsomedegreeapplicableinothercases，Iwillherebrieflygivethem。Iftheseveralbreedsarenotvarieties，andhavenotproceededfromtherock-pigeon，theymusthavedescendedfromatleastsevenoreightaboriginalstocks。foritisimpossibletomakethepresentdomesticbreedsbythecrossingofanylessernumber：how，forinstance，couldapouterbeproducedbycrossingtwobreedsunlessoneoftheparent-stockspossessedthecharacteristicenormouscrop？Thesupposedaboriginalstocksmustallhavebeenrock-pigeons，thatis，notbreedingorwillinglyperchingontrees。ButbesidesC。livia，withitsgeographicalsub-species，onlytwoorthreeotherspeciesofrock-pigeonsareknown。andthesehavenotanyofthecharactersofthedomesticbreeds。

Hencethesupposedaboriginalstocksmusteitherstillexistinthecountrieswheretheywereoriginallydomesticated，andyetbeunknowntoornithologists。

andthis，consideringtheirsize，habits，andremarkablecharacters，seemsveryimprobable。ortheymusthavebecomeextinctinthewildstate。Butbirdsbreedingonprecipices，andgoodfliers，areunlikelytobeexterminated。

andthecommonrock-pigeon，whichhasthesamehabitswiththedomesticbreeds，hasnotbeenexterminatedevenonseveralofthesmallerBritishislets，orontheshoresoftheMediterranean。Hencethesupposedexterminationofsomanyspecieshavingsimilarhabitswiththerock-pigeonseemstomeaveryrashassumption。Moreover，theseveralabove-nameddomesticatedbreedshavebeentransportedtoallpartsoftheworld，and，therefore，someofthemmusthavebeencarriedbackagainintotheirnativecountry。

butnotonehaseverbecomewildorferal，thoughthedovecot-pigeon，whichistherock-pigeoninaveryslightlyalteredstate，hasbecomeferalinseveralplaces。Again，allrecentexperienceshowsthatitismostdifficulttogetanywildanimaltobreedfreelyunderdomestication。yetonthehypothesisofthemultipleoriginofourpigeons，itmustbeassumedthatatleastsevenoreightspeciesweresothoroughlydomesticatedinancienttimesbyhalf-civilizedman，astobequiteprolificunderconfinement。

Anargument，asitseemstome，ofgreatweight，andapplicableinseveralothercases，is，thattheabove-specifiedbreeds，thoughagreeinggenerallyinconstitution，habits，voice，colouring，andinmostpartsoftheirstructure，withthewildrock-pigeon，yetarecertainlyhighlyabnormalinotherpartsoftheirstructure：wemaylookinvainthroughoutthewholegreatfamilyofColumbidaeforabeaklikethatoftheEnglishcarrier，orthatoftheshort-facedtumbler，orbarb。forreversedfeatherslikethoseofthejacobin。

foracroplikethatofthepouter。fortail-featherslikethoseofthefantail。Henceitmustbeassumednotonlythathalf-civilizedmansucceededinthoroughlydomesticatingseveralspecies，butthatheintentionallyorbychancepickedoutextraordinarilyabnormalspecies。andfurther，thattheseveryspecieshavesinceallbecomeextinctorunknown。Somanystrangecontingenciesseemtomeimprobableinthehighestdegree。

Somefactsinregardtothecolouringofpigeonswelldeserveconsideration。

Therock-pigeonisofaslaty-blue，andhasawhiterump(theIndiansub-species，C。intermediaofStrickland，havingitbluish)。thetailhasaterminaldarkbar，withthebasesoftheouterfeathersexternallyedgedwithwhite。

thewingshavetwoblackbars：somesemi-domesticbreedsandsomeapparentlytrulywildbreedshave，besidesthetwoblackbars，thewingschequeredwithblack。Theseseveralmarksdonotoccurtogetherinanyotherspeciesofthewholefamily。Now，ineveryoneofthedomesticbreeds，takingthoroughlywell-bredbirds，alltheabovemarks，eventothewhiteedgingoftheoutertail-feathers，sometimesconcurperfectlydeveloped。Moreover，whentwobirdsbelongingtotwodistinctbreedsarecrossed，neitherofwhichisblueorhasanyoftheabove-specifiedmarks，themongreloffspringareveryaptsuddenlytoacquirethesecharacters。forinstance，Icrossedsomeuniformlywhitefantailswithsomeuniformlyblackbarbs，andtheyproducedmottledbrownandblackbirds。theseIagaincrossedtogether，andonegrandchildofthepurewhitefantailandpureblackbarbwasofasbeautifulabluecolour，withthewhiterump，doubleblackwing-bar，andbarredandwhite-edgedtail-feathers，asanywildrock-pigeon！Wecanunderstandthesefacts，onthewell-knownprincipleofreversiontoancestralcharacters，ifallthedomesticbreedshavedescendedfromtherock-pigeon。

Butifwedenythis，wemustmakeoneofthetwofollowinghighlyimprobablesuppositions。Either，firstly，thatalltheseveralimaginedaboriginalstockswerecolouredandmarkedliketherock-pigeon，althoughnootherexistingspeciesisthuscolouredandmarked，sothatineachseparatebreedtheremightbeatendencytoreverttotheverysamecoloursandmarkings。Or，secondly，thateachbreed，eventhepurest，haswithinadozenor，atmost，withinascoreofgenerations，beencrossedbytherock-pigeon：

Isaywithinadozenortwentygenerations，forweknowofnofactcountenancingthebeliefthatthechildeverrevertstosomeoneancestor，removedbyagreaternumberofgenerations。Inabreedwhichhasbeencrossedonlyoncewithsomedistinctbreed，thetendencytoreversiontoanycharacterderivedfromsuchcrosswillnaturallybecomelessandless，asineachsucceedinggenerationtherewillbelessoftheforeignblood。butwhentherehasbeennocrosswithadistinctbreed，andthereisatendencyinbothparentstoreverttoacharacter，whichhasbeenlostduringsomeformergeneration，thistendency，forallthatwecanseetothecontrary，maybetransmittedundiminishedforanindefinitenumberofgenerations。

Thesetwodistinctcasesareoftenconfoundedintreatisesoninheritance。

Lastly，thehybridsormongrelsfrombetweenallthedomesticbreedsofpigeonsareperfectlyfertile。Icanstatethisfrommyownobservations，purposelymadeonthemostdistinctbreeds。Now，itisdifficult，perhapsimpossible，tobringforwardonecaseofthehybridoffspringoftwoanimalsclearlydistinctbeingthemselvesperfectlyfertile。Someauthorsbelievethatlong-continueddomesticationeliminatesthisstrongtendencytosterility：fromthehistoryofthedogIthinkthereissomeprobabilityinthishypothesis，ifappliedtospeciescloselyrelatedtogether，thoughitisunsupportedbyasingleexperiment。Buttoextendthehypothesissofarastosupposethatspecies，aboriginallyasdistinctascarriers，tumblers，pouters，andfantailsnoware，shouldyieldoffspringperfectlyfertile，interse，seemstomerashintheextreme。

Fromtheseseveralreasons，namely，theimprobabilityofmanhavingformerlygotsevenoreightsupposedspeciesofpigeonstobreedfreelyunderdomestication。thesesupposedspeciesbeingquiteunknowninawildstate，andtheirbecomingnowhereferal。thesespecieshavingveryabnormalcharactersincertainrespects，ascomparedwithallotherColumbidae，thoughsolikeinmostotherrespectstotherock-pigeon。thebluecolourandvariousmarksoccasionallyappearinginallthebreeds，bothwhenkeptpureandwhencrossed。themongreloffspringbeingperfectlyfertile。fromtheseseveralreasons，takentogether，IcanfeelnodoubtthatallourdomesticbreedshavedescendedfromtheColumbaliviawithitsgeographicalsub-species。

Infavourofthisview，Imayadd，firstly，thatC。livia，ortherock-pigeon，hasbeenfoundcapableofdomesticationinEuropeandinIndia。andthatitagreesinhabitsandinagreatnumberofpointsofstructurewithallthedomesticbreeds。Secondly，althoughanEnglishcarrierorshort-facedtumblerdiffersimmenselyincertaincharactersfromtherock-pigeon，yetbycomparingtheseveralsub-breedsofthesebreeds，moreespeciallythosebroughtfromdistantcountries，wecanmakeanalmostperfectseriesbetweentheextremesofstructure。Thirdly，thosecharacterswhicharemainlydistinctiveofeachbreed，forinstancethewattleandlengthofbeakofthecarrier，theshortnessofthatofthetumbler，andthenumberoftail-feathersinthefantail，areineachbreedeminentlyvariable。andtheexplanationofthisfactwillbeobviouswhenwecometotreatofselection。Fourthly，pigeonshavebeenwatched，andtendedwiththeutmostcare，andlovedbymanypeople。Theyhavebeendomesticatedforthousandsofyearsinseveralquartersoftheworld。theearliestknownrecordofpigeonsisinthefifthAegyptiandynasty，about3000B。C。，aswaspointedouttomebyProfessorLepsius。butMrBirchinformsmethatpigeonsaregiveninabilloffareinthepreviousdynasty。InthetimeoftheRomans，aswehearfromPliny，immensepricesweregivenforpigeons。’nay，theyarecometothispass，thattheycanreckonuptheirpedigreeandrace。’PigeonsweremuchvaluedbyAkberKhaninIndia，abouttheyear1600。neverlessthan20，000pigeonsweretakenwiththecourt。’ThemonarchsofIranandTuransenthimsomeveryrarebirds。’and，continuesthecourtlyhistorian，’HisMajestybycrossingthebreeds，whichmethodwasneverpractisedbefore，hasimprovedthemastonishingly。’AboutthissameperiodtheDutchwereaseageraboutpigeonsasweretheoldRomans。Theparamountimportanceoftheseconsiderationsinexplainingtheimmenseamountofvariationwhichpigeonshaveundergone，willbeobviouswhenwetreatofSelection。Weshallthen，also，seehowitisthatthebreedssooftenhaveasomewhatmonstrouscharacter。Itisalsoamostfavourablecircumstancefortheproductionofdistinctbreeds，thatmaleandfemalepigeonscanbeeasilymatedforlife。andthusdifferentbreedscanbekepttogetherinthesameaviary。

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