第17章
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  (8/39。’OrnamentalPoetry’bytheRev。E。S。Dixon1848page34。)Theinferiortail—covertsvaryinnumber,andaccordingtoaGermansuperstitionthehenlaysasmanyeggsasthecockhasfeathersofthiskind。(8/40。Bechstein’Naturgesch。Deutschlands’b。31793s。309。)Albinin1738,andTemminckwithinamuchlaterperiod,describeabeautifulbreed,dusky—yellowish,brownaboveandwhitebeneath,withalargetop—

  knotofsoftplumosefeather。Thespursofthemalewererudimentary。ThisbreedhasbeenforalongtimeextinctinEurope;butalivingspecimenhaslatelybeenimportedfromtheeastcoastofAfrica,whichstillretainsthetop—knotandthesamegeneralcolouringandrudimentaryspurs。(8/41。Mr。

  Bartlettin’LandandWater’October31,1868page233;andMr。Tegetmeierinthe’Field’July17,1869page46。)Mr。Wilmothasdescribed(8/42。

  ’Gardener’sChronicle’1852page699。)awhiteturkey—cockhavingacrestformedof\"feathersaboutfourincheslong,withbarequills,andatuftofsoftwhitedowngrowingattheend。\"Manyoftheyoungbirdsinheritedthiskindofcrest,butafterwardsitfellofforwaspeckedoutbytheotherbirds。Thisisaninterestingcase,aswithcareanewbreedmightprobablyhavebeenformed;andatop—knotofthisnaturewouldhavebeentoacertainextentanalogoustothatbornebythemalesinseveralalliedgenera,suchasEuplocomus,Lophophorus,andPavo。

  Wildturkeys,believedineveryinstancetohavebeenimportedfromtheUnitedStates,havebeenkeptintheparksofLordsPowis,Leicester,Hill,andDerby。TheRev。W。D。Foxprocuredbirdsfromthetwofirst—namedparks,andheinformsmethattheycertainlydifferedalittlefromeachotherintheshapeoftheirbodiesandinthebarredplumageontheirwings。ThesebirdslikewisedifferedfromLordHill’sstock。SomeofthelatterkeptatOultonbySirP。Egerton,thoughprecludedfromcrossingwithcommonturkeys,occasionallyproducedmuchpaler—colouredbirds,andonethatwasalmostwhite,butnotanalbino。Thesehalf—wildturkeys,inthusdifferingslightlyfromeachother,presentananalogouscasewiththewildcattlekeptintheseveralBritishparks。Wemustsupposethatsuchdifferenceshaveresultedfromthepreventionoffreeintercrossingbetweenbirdsrangingoverawidearea,andfromthechangedconditionstowhichtheyhavebeenexposedinEngland。InIndiatheclimatehasapparentlywroughtastillgreaterchangeintheturkey,foritisdescribedbyMr。Blyth(8/43。

  E。Blyth’AnnalsandMag。ofNat。Hist。’1847volume20page391。)asbeingmuchdegeneratedinsize,\"utterlyincapableofrisingonthewing,\"ofablackcolour,and\"withthelongpendulousappendagesoverthebeakenormouslydeveloped。\"

  THEGUINEAFOWL。

  ThedomesticatedGuineafowlisnowbelievedbysomenaturaliststobedescendedfromtheNumidaptilorhynca,whichinhabitsveryhot,and,inparts,extremelyariddistrictsinEasternAfrica;consequentlyithasbeenexposedinthiscountrytoextremelydifferentconditionsoflife。

  Neverthelessithashardlyvariedatall,exceptintheplumagebeingeitherpalerordarker—coloured。ItisasingularfactthatthisbirdvariesmoreincolourintheWestIndiesandontheSpanishMain,underahotthoughhumidclimate,thaninEurope。(8/44。Roulinmakesthisremarkin’Mem。dediversSavans,1’Acad。desSciences’tome61835page349。Mr。

  HillofSpanishTowninalettertomedescribesfivevarietiesoftheGuineafowlinJamaica。Ihaveseensingularpale—colouredvarietiesimportedfromBarbadoesandDemerara。)TheGuineafowlhasbecomethoroughlyferalinJamaicaandinSt。Domingo(8/45。ForSt。DomingoseeM。A。Salle,in’Proc。Zoolog。Soc。’1857page236。Mr。Hillremarkstome,inhisletter,onthecolourofthelegsoftheferalbirdsinJamaica。),andhasdiminishedinsize;thelegsareblack,whereasthelegsoftheaboriginalAfricanbirdaresaidtobegrey。Thissmallchangeisworthnoticeonaccountoftheoften—repeatedstatementthatallferalanimalsinvariablyrevertineverycharactertotheiroriginaltype。

  THECANARYBIRD。

  Asthisbirdhasbeenrecentlydomesticated,namely,withinthelast350

  years,itsvariabilitydeservesnotice。IthasbeencrossedwithnineortenotherspeciesofFringillidae,andsomeofthehybridsarealmostcompletelyfertile;butwehavenoevidencethatanydistinctbreedhasoriginatedfromsuchcrosses。Notwithstandingthemoderndomesticationofthecanary,manyvarietieshavebeenproduced;evenbeforetheyear1718alistoftwenty—sevenvarietieswaspublishedinFrance(8/46。Mr。B。P。

  Brent’TheCanary,BritishFinches’etc。pages21,30。),andin1779alongscheduleofthedesiredqualitieswasprintedbytheLondonCanarySociety,sothatmethodicalselectionhasbeenpractisedduringaconsiderableperiod。Thegreaternumberofthevarietiesdifferonlyincolourandinthemarkingsoftheirplumage。Somebreedshowever,differinshape,suchasthehoopedorbowedcanaries,andtheBelgiancanarieswiththeirmuchelongatedbodies。Mr。Brent(8/47。’CottageGardener’December11,1855

  page184:anaccountisheregivenofallthevarieties。Formanymeasurementsofthewildbirds,seeMr。E。VernonHarcourtibidDecember25,1855page223。)measuredoneofthelatterandfounditeightinchesinlength,whilstthewildcanaryisonlyfiveandaquarterincheslong。

  Therearetop—knottedcanaries,anditisasingularfactthat,iftwotop—

  knottedbirdsarematched,theyoung,insteadofhavingveryfinetop—

  knots,aregenerallybald,orevenhaveawoundontheirheads。(8/48。

  Bechstein’Naturgesch。derStubenvogel’1840s。243;sees。252ontheinheritedsongofCanary—birds。WithrespecttotheirbaldnessseealsoW。

  Kidd’TreatiseonSong—Birds。’)Itwouldappearasifthetop—knotwereduetosomemorbidcondition,whichisincreasedtoaninjuriousdegreewhentwobirdsinthisstatearepaired。Thereisafeather—footedbreed,andanotherwithakindoffrillrunningdownthebreast。Oneothercharacterdeservesnoticefrombeingconfinedtooneperiodoflife,andfrombeingstrictlyinheritedatthesameperiod;namely,thewingandtailfeathersinprizecanariesbeingblack,\"butthiscolourisretainedonlyuntilthefirstmoult;oncemoulted,thepeculiarityceases。\"(8/49。W。Kidd’TreatiseonSong—Birds’page18。)Canariesdiffermuchindispositionandcharacter,andinsomesmalldegreeinsong。Theyproduceeggsthreeorfourtimesduringtheyear。

  GOLD—FISH。

  Besidesmammalsandbirds,onlyafewanimalsbelongingtotheothergreatclasseshavebeendomesticated;buttoshowthatitisanalmostuniversallawthatanimals,whenremovedfromtheirnaturalconditionsoflife,vary,andthatracescanbeformedwhenselectionisapplied,itisnecessarytosayafewwordsongold—fish,bees,andsilk—moths。

  Gold—fish(Cyprinusauratus)wereintroducedintoEuropeonlytwoorthreecenturiesago;buttheyhavebeenkeptinconfinementfromanancientperiodinChina。Mr。Blyth(8/50。The’IndianField’1858page255。)

  suspects,fromtheanalogousvariationofotherfishes,thatgolden—

  colouredfishdonotoccurinastateofnature。Thesefishesfrequentlyliveunderthemostunnaturalconditions,andtheirvariabilityincolour,size,andinsomeimportantpointsofstructureisverygreat。M。Sauvignyhasdescribedandgivencoloureddrawingsofnolessthaneighty—ninevarieties。(8/51。Yarrell’BritishFishes’volume1page319。)Manyofthevarieties,however,suchastripletail—fins,etc。,oughttobecalledmonstrosities;butitisdifficulttodrawanydistinctlinebetweenavariationandamonstrosity。Asgold—fisharekeptforornamentorcuriosity,andas\"theChinesearejustthepeopletohavesecludedachancevarietyofanykind,andtohavematchedandpairedfromit\"(8/52。

  Mr。Blythinthe’IndianField’1858page255。),itmighthavebeenpredictedthatselectionwouldhavebeenlargelypractisedintheformationofnewbreeds;andthisisthecase。InanoldChineseworkitissaidthatfishwithvermilionscaleswerefirstraisedinconfinementduringtheSungdynasty(whichcommencedA。D。960),\"andnowtheyarecultivatedinfamilieseverywhereforthesakeofornament。\"Inanotherandmoreancientwork,itissaidthat\"thereisnotahouseholdwherethegold—fishisnotcultivated,inRIVALRYastoitscolour,andasasourceofprofit,\"etc。

  (8/53。W。F。Mayers’ChineseNotesandQueries’August1868page123。)

  Althoughmanybreedsexist,itisasingularfactthatthevariationsareoftennotinherited。SirR。Heron(8/54。’Proc。Zoolog。Soc。’May25,1842。)keptmanyofthesefishes,andplacedallthedeformedones,namely,thosedestituteofdorsalfinsandthosefurnishedwithadoubleanalfin,ortripletail,inapondbythemselves;buttheydid\"notproduceagreaterproportionofdeformedoffspringthantheperfectfishes。\"

  Passingoveranalmostinfinitediversityofcolour,wemeetwiththemostextraordinarymodificationsofstructure。Thus,outofabouttwodozenspecimensboughtinLondon,Mr。Yarrellobservedsomewiththedorsalfinextendingalongmorethanhalfthelengthoftheback:otherswiththisfinreducedtoonlyfiveorsixrays:andonewithnodorsalfin。Theanalfinsaresometimesdouble,andthetailisoftentriple。Thislatterdeviationofstructureseemsgenerallytooccur\"attheexpenseofthewholeorpartofsomeotherfin(8/55。Yarrell’BritishFishes’volume1page319。);butBorydeSaint—Vincent(8/56。’Dict。Class。d’Hist。Nat。’tome5page276。)

  sawatMadridgold—fishfurnishedwithadorsalfinandatripletail。Onevarietyischaracterisedbyahumponitsbacknearthehead;andtheRev。

  L。Jenyns(Blomefield)(8/57。’ObservationsinNat。Hist。’1846page211。

  Dr。Grayhasdescribedin’AnnalsandMag。ofNat。Hist。’1860page151anearlysimilarvarietybutdestituteofadorsalfin。)hasdescribedamostsingularvariety,importedfromChina,almostglobularinformlikeaDiodon,with\"thefleshypartofthetailasifentirelycutaway?thecaudalfinbeingsetonalittlebehindthedorsalandimmediatelyabovetheanal。\"Inthisfishtheanalandcaudalfinsweredouble;theanalfinbeingattachedtothebodyinaverticalline:theeyesalsowereenormouslylargeandprotuberant。

  HIVE—BEES。

  Beeshavebeendomesticatedfromanancientperiod;ifindeedtheirstatecanbeconsideredoneofdomestication,fortheysearchfortheirownfood,withtheexceptionofalittlegenerallygiventothemduringthewinter。

  Theirhabitationisahiveinsteadofaholeinatree。Bees,however,havebeentransportedintoalmosteveryquarteroftheworld,sothatclimateoughttohaveproducedwhateverdirecteffectitiscapableofproducing。

  ItisfrequentlyassertedthatthebeesindifferentpartsofGreatBritaindifferinsize,colour,andtemper;andGodron(8/58。’Del’Espece’1859

  page459。WithrespecttothebeesofBurgundyseeM。Gerard,art。’Espece’

  in’Dict。Univers。d’Hist。Nat。’)saysthattheyaregenerallylargerinthesouththaninotherpartsofFrance;ithasalsobeenassertedthatthelittlebrownbeesofHighBurgundy,whentransportedtoLaBressebecomelargeandyellowinthesecondgeneration。Butthesestatementsrequireconfirmation。Asfarassizeisconcerned,itisknownthatbeesproducedinveryoldcombsaresmaller,owingtothecellshavingbecomesmallerfromthesuccessiveoldcocoons。Thebestauthorities(8/59。Seeadiscussiononthissubject,inanswertoaquestionofmine,in’JournalofHorticulture’1862pages225—242;alsoMr。BevanFoxinditto1862page284)concurthat,withtheexceptionoftheLigurianraceorspecies,presentlytobementioned,distinctbreedsdonotexistinBritainorontheContinent。Thereis,however,eveninthesamestock,somevariabilityincolour。Thus,Mr。Woodburystates(8/60。Thisexcellentobservermaybeimplicitlytrusted;see’JournalofHorticulture’July14,1863page39。)

  thathehasseveraltimesseenqueenbeesofthecommonkindannulatedwithyellow—likeLigurianqueens,andthelatterdark—colouredlikecommonbees。

  Hehasalsoobservedvariationsinthecolourofthedrones,withoutanycorrespondingdifferenceinthequeensorworkersofthesamehive。Thegreatapiarian,Dzierzon,inanswertomyqueriesonthissubject,says(8/61。’JournalofHorticulture’September9,1862page463;seealsoHerrKleineonsamesubjectNovember11page643,whosumsup,that,thoughthereissomevariabilityincolour,noconstantorperceptibledifferencescanbedetectedinthebeesofGermany。),thatinGermanybeesofsomestocksaredecidedlydark,whilstothersareremarkablefortheiryellowcolour。Beesalsoseemtodifferinhabitsindifferentdistricts,forDzierzonadds,\"Ifmanystockswiththeiroffspringaremoreinclinedtoswarm,whilstothersarericherinhoney,sothatsomebee—keepersevendistinguishbetweenswarmingandhoney—gatheringbees,thisisahabitwhichhasbecomesecondnature,causedbythecustomarymodeofkeepingthebeesandthepasturageofthedistrict。Forexample,whatadifferenceinthisrespectonemayperceivetoexistbetweenthebeesoftheLuneburgheathandthoseofthiscountry!\"……\"Removinganoldqueenandsubstitutingayoungoneofthecurrentyearishereaninfalliblemodeofkeepingthestrongeststockfromswarmingandpreventingdrone—breeding;whilstthesamemeansifadoptedinHanoverwouldcertainlybeofnoavail。\"I

  procuredahivefullofdeadbeesfromJamaica,wheretheyhavelongbeennaturalised,and,oncarefullycomparingthemunderthemicroscopewithmyownbees,Icoulddetectnotatraceofdifference。

  Thisremarkableuniformityinthehive—bee,whereverkept,mayprobablybeaccountedforbythegreatdifficulty,orratherimpossibility,ofbringingselectionintoplaybypairingparticularqueensanddrones,fortheseinsectsuniteonlyduringflight。Noristhereanyrecord,withasinglepartialexception,ofanypersonhavingseparatedandbredfromahiveinwhichtheworkerspresentedsomeappreciabledifference。Inordertoformanewbreed,seclusionfromotherbeeswould,aswenowknow,beindispensable;forsincetheintroductionoftheLigurianbeeintoGermanyandEngland,ithasbeenfoundthatthedroneswanderatleasttwomilesfromtheirownhives,andoftencrosswiththequeensofthecommonbee。

  (8/62。Mr。Woodburyhaspublishedseveralsuchaccountsin’JournalofHorticulture’1861and1862。)TheLigurianbee,althoughperfectlyfertilewhencrossedwiththecommonkind,isrankedbymostnaturalistsasadistinctspecies,whilstbyothersitisrankedasavariety:butthisformneednotherebenoticed,asthereisnoreasontobelievethatitistheproductofdomestication。TheEgyptianandsomeotherbeesarelikewiserankedbyDr。Gerstacker(8/63。’AnnalsandMag。ofNat。Hist。’3rdseriesvolume11page339。)butnotbyotherhighlycompetentjudges,asgeographicalraces;hegroundshisconclusioninchiefpartonthefactthatincertaindistricts,asintheCrimeaandRhodes,theyvarysomuchincolour,thattheseveralgeographicalracescanbecloselyconnectedbyintermediateforms。

  Ihavealludedtoasingleinstanceoftheseparationandpreservationofaparticularstockofbees。Mr。Lowe(8/64。’TheCottageGardener’May1860

  page110;anddittoin’JournalofHort。’1862page242。)procuredsomebeesfromacottagerafewmilesfromEdinburgh,andperceivedthattheydifferedfromthecommonbeeinthehairsontheheadandthoraxbeinglightercolouredandmoreprofuseinquantity。FromthedateoftheintroductionoftheLigurianbeeintoGreatBritainwemayfeelsurethatthesebeeshadnotbeencrossedwiththisform。Mr。Lowepropagatedthisvariety,butunfortunatelydidnotseparatethestockfromhisotherbees,andafterthreegenerationsthenewcharacterwasalmostcompletelylost。

  Nevertheless,asheadds,\"agreatnumberofthebeesstillretaintraces,thoughfaint,oftheoriginalcolony。\"Thiscaseshowsuswhatcouldprobablybeeffectedbycarefulandlong—continuedselectionappliedexclusivelytotheworkers,for,aswehaveseen,queensanddronescannotbeselectedandpaired。

  SILK—MOTHS。

  Theseinsectsareinseveralrespectsinterestingtous,moreespeciallybecausetheyhavevariedlargelyatanearlyperiodoflife,andthevariationshavebeeninheritedatcorrespondingperiods。Asthevalueofthesilk—mothdependsentirelyonthecocoon,everychangeinitsstructureandqualitieshasbeencarefullyattendedto,andracesdifferingmuchinthecocoon,buthardlyatallintheadultstate,havebeenproduced。Withtheracesofmostotherdomesticanimals,theyoungresembleeachotherclosely,whilsttheadultsdiffermuch。

  Itwouldbeuseless,evenifitwerepossible,todescribeallthemanykindsofsilkworms。SeveraldistinctspeciesexistinIndiaandChinawhichproduceusefulsilk,andsomeofthesearecapableoffreelycrossingwiththecommonsilk—moth,ashasbeenrecentlyascertainedinFrance。CaptainHutton(8/65。’Transact。Entomolog。Soc。’3rdseriesvolume3pages143—173

  andpages295—331。)statesthatthroughouttheworldatleastsixspecieshavebeendomesticated;andhebelievesthatthesilk—mothsrearedinEuropebelongtotwoorthreespecies。This,however,isnottheopinionofseveralcapablejudgeswhohaveparticularlyattendedtothecultivationofthisinsectinFrance;andhardlyaccordswithsomefactspresentlytobegiven。

  Thecommonsilk—moth(Bombyxmori)wasbroughttoConstantinopleinthesixthcentury,whenceitwascarriedintoItaly,andin1494intoFrance。

  (8/66。Godron’Del’Espece’1859tome1page460。TheantiquityofthesilkworminChinaisgivenontheauthorityofStanislasJulien。)

  Everythinghasbeenfavourableforthevariationofthisinsect。ItisbelievedtohavebeendomesticatedinChinaaslongagoas2700B。C。Ithasbeenkeptunderunnaturalanddiversifiedconditionsoflife,andhasbeentransportedintomanycountries。Thereisreasontobelievethatthenatureofthefoodgiventothecaterpillarinfluencestoacertainextentthecharacterofthebreed。(8/67。SeetheremarksofProf。Westwood,Gen。

  HearseyandothersatthemeetingoftheEntomolog。Soc。ofLondonJuly1861。)Disusehasapparentlyaidedincheckingthedevelopmentofthewings。Butthemostimportantelementintheproductionofthemanynowexisting,muchmodifiedraces,nodoubthasbeenthecloseattentionwhichhaslongbeenappliedinmanycountriestoeverypromisingvariation。ThecaretakeninEuropeintheselectionofthebestcocoonsandmothsforbreedingisnotorious(8/68。SeeforinstanceM。A。deQuatrefages’EtudessurlesMaladiesactuellesduVeraSoie’1859page101。),andtheproductionofeggsisfollowedasadistincttradeinpartsofFrance。I

  havemadeinquiriesthroughDr。Falconer,andamassuredthatinIndiathenativesareequallycarefulintheprocessofselection。InChinatheproductionofeggsisconfinedtocertainfavourabledistricts,andtheraisersareprecludedbylawfromproducingsilk,sothattheirwholeattentionmaybenecessarilygivenuptothisoneobject。(8/69。MyauthoritiesforthestatementswillbegiveninthechapteronSelection。)

  [Thefollowingdetailsonthedifferencesbetweentheseveralbreedsaretaken,whennotstatedtothecontrary,fromM。Robinet’sexcellentwork(8/70。’Manueldel’EducateurdeVersaSoie’1848。),whichbearseverysignofcareandlargeexperience。TheEGGSinthedifferentracesvaryincolour,inshape(beinground,ellipticoroval),andinsize。TheeggslaidinJuneinthesouthofFrance,andinJulyinthecentralprovinces,donothatchuntilthefollowingspring;anditisinvain,saysM。

  Robinet,toexposethemtoatemperaturegraduallyraised,inorderthatthecaterpillarmaybequicklydeveloped。Yetoccasionally,withoutanyknowncause,batchesofeggsareproduced,whichimmediatelybegintoundergotheproperchanges,andarehatchedinfromtwentytothirtydays。

  FromtheseandsomeotheranalogousfactsitmaybeconcludedthattheTrevoltinisilkwormsofItaly,ofwhichthecaterpillarsarehatchedinfromfifteentotwentydays,donotnecessarilyform,ashasbeenmaintained,adistinctspecies。Althoughthebreedswhichliveintemperatecountriesproduceeggswhichcannotbeimmediatelyhatchedbyartificialheat,yetwhentheyareremovedtoandrearedinahotcountrytheygraduallyacquirethecharacterofquickdevelopment,asintheTrevoltiniraces。(8/71。Robinetibidpages12,318。ImayaddthattheeggsofN。

  AmericansilkwormstakentotheSandwichIslandsproducedmothsatveryirregularperiods;andthemothsthusraisedyieldedeggswhichwereevenworseinthisrespect。Somewerehatchedintendays,andothersnotuntilafterthelapseofmanymonths。Nodoubtaregularearlycharacterwouldultimatelyhavebeenacquired。Seereviewin’Athenaeum’1844page329ofJ。Jarves’ScenesintheSandwichIslands。’)

  CATERPILLARS。

  Thesevarygreatlyinsizeandcolour。Theskinisgenerallywhite,sometimesmottledwithblackorgrey,andoccasionallyquiteblack。Thecolour,however,asM。Robinetasserts,isnotconstant,eveninperfectlypurebreeds;exceptintheracetigree,socalledfrombeingmarkedwithtransverseblackstripes。Asthegeneralcolourofthecaterpillarisnotcorrelatedwiththatofthesilk(8/72。’TheArtofrearingSilkworms’

  translatedfromCountDandolo1825page23。),thischaracterisdisregardedbycultivators,andhasnotbeenfixedbyselection。CaptainHutton,inthepaperbeforereferredto,hasarguedwithmuchforcethatthedarktiger—

  likemarks,whichsofrequentlyappearduringthelatermoultsinthecaterpillarsofvariousbreeds,areduetoreversion;forthecaterpillarsofseveralalliedwildspeciesofBombyxaremarkedandcolouredinthismanner。Heseparatedsomecaterpillarswiththetiger—likemarks,andinthesucceedingspring(pages149,298)nearlyallthecaterpillarsrearedfromthemweredark—brindled,andthetintsbecamestilldarkerinthethirdgeneration。Themothsrearedfromthesecaterpillars(8/73。

  ’Transact。Ent。Soc。’utsuprapages153,308。)alsobecamedarker,andresembledincolouringthewildB。huttoni。Onthisviewofthetiger—likemarksbeingduetoreversion,thepersistencywithwhichtheyaretransmittedisintelligible。

  SeveralyearsagoMrs。Whitbytookgreatpainsinbreedingsilkwormsonalargescale,andsheinformedmethatsomeofhercaterpillarshaddarkeyebrows。Thisisprobablythefirststepinreversiontowardsthetiger—

  likemarks,andIwascurioustoknowwhethersotriflingacharacterwouldbeinherited。Atmyrequestsheseparatedin1848twentyofthesecaterpillars,andhavingkeptthemothsseparate,bredfromthem。Ofthemanycaterpillarsthusreared,\"everyonewithoutexceptionhadeyebrows,somedarkerandmoredecidedlymarkedthantheothers,butALLhadeyebrowsmoreorlessplainlyvisible。\"Blackcaterpillarsoccasionallyappearamongstthoseofthecommonkind,butinsovariableamanner,that,accordingtoM。Robinet,thesameracewilloneyearexclusivelyproducewhitecaterpillars,andthenextyearmanyblackones;nevertheless,IhavebeeninformedbyM。A。BossiofGeneva,that,iftheseblackcaterpillarsareseparatelybredfrom,theyreproducethesamecolour;butthecocoonsandmothsrearedfromthemdonotpresentanydifference。

  ThecaterpillarinEuropeordinarilymoultsfourtimesbeforepassingintothecocoonstage;butthereareraces\"atroismues,\"andtheTrevoltiniracelikewisemoultsonlythrice。Itmighthavebeenthoughtthatsoimportantaphysiologicaldifferencewouldnothavearisenunderdomestication;butM。Robinet(8/74。Robinetibidpage317。)statesthat,ontheonehand,ordinarycaterpillarsoccasionallyspintheircocoonsafteronlythreemoults,and,ontheotherhand,\"presquetouteslesracesatroismues,quenousavonsexperimentees,ontfaitquatremuesalasecondeoualatroisiemeannee,cequisembleprouverqu’ilasuffidelesplacerdansdesconditionsfavorablespourleurrendreunefacultequ’ellesavaientperduesousdesinfluencesmoinsfavorables。\"

  COCOONS。

  Thecaterpillarinchangingintothecocoonlosesabout50percentofitsweight;buttheamountoflossdiffersindifferentbreeds,andthisisofimportancetothecultivator。Thecocooninthedifferentracespresentscharacteristicdifferences;beinglargeorsmall;——nearlysphericalwithnoconstriction,asintheRacedeLoriol,orcylindrical,witheitheradeeporslightconstrictioninthemiddle;withthetwoends,orwithoneendalone,moreorlesspointed。Thesilkvariesinfinenessandquality,andinbeingnearlywhite,butoftwotints,oryellow。Generallythecolourofthesilkisnotstrictlyinherited:butinthechapteronSelectionIshallgiveacuriousaccounthow,inthecourseofsixty—fivegenerations,thenumberofyellowcocoonsinonebreedhasbeenreducedinFrancefromonehundredtothirty—fiveinthethousand。AccordingtoRobinet,thewhiterace,calledSina,bycarefulselectionduringthelastseventy—fiveyears,\"estarriveeaunteletatdepurete,qu’onnevoitpasunseulcoconjaunedansdesmillionsdecoconsblancs。\"(8/75。Robinetibidpages306—317。)

  Cocoonsaresometimesformed,asiswellknown,entirelydestituteofsilk,whichyetproducemoths;unfortunatelyMrs。Whitbywaspreventedbyanaccidentfromascertainingwhetherthischaracterwouldprovehereditary。

  ADULTSTAGE。

  Icanfindnoaccountofanyconstantdifferenceinthemothsofthemostdistinctraces。Mrs。Whitbyassuredmethattherewasnoneintheseveralkindsbredbyher;andIhavereceivedasimilarstatementfromtheeminentnaturalist,M。deQuatrefages。CaptainHuttonalsosays(8/76。’Transact。

  Ent。Soc。’utsuprapage317。)thatthemothsofallkindsvarymuchincolour,butinnearlythesameinconstantmanner。Consideringhowmuchthecocoonsintheseveralracesdiffer,thisfactisofinterest,andmayprobablybeaccountedforonthesameprincipleasthefluctuatingvariabilityofcolourinthecaterpillar,namely,thattherehasbeennomotiveforselectingandperpetuatinganyparticularvariation。

  ThemalesofthewildBombycidae\"flyswiftlyintheday—timeandevening,butthefemalesareusuallyverysluggishandinactive。\"(8/77。Stephen’sIllustrations,’Haustellata’volume2page35。SeealsoCapt。Hutton’Transact。Ent。Soc。’ibidpage152。)Inseveralmothsofthisfamilythefemaleshaveabortivewings,butnoinstanceisknownofthemalesbeingincapableofflight,forinthiscasethespeciescouldhardlyhavebeenperpetuated。Inthesilk—mothbothsexeshaveimperfect,crumpledwings,andareincapableofflight;butstillthereisatraceofthecharacteristicdifferenceinthetwosexes;forthough,oncomparinganumberofmalesandfemales,Icoulddetectnodifferenceinthedevelopmentoftheirwings,yetIwasassuredbyMrs。Whitbythatthemalesofthemothsbredbyherusedtheirwingsmorethanthefemales,andcouldflutterdownwards,thoughneverupwards。Shealsostatesthat,whenthefemalesfirstemergefromthecocoon,theirwingsarelessexpandedthanthoseofthemale。Thedegreeofimperfection,however,inthewingsvariesmuchindifferentracesandunderdifferentcircumstances。M。Quatrefages(8/78。’EtudessurlesMaladiesduVeraSoie’1859pages304,209。)saysthathehasseenanumberofmothswiththeirwingsreducedtoathird,fourth,ortenthpartoftheirnormaldimensions,andeventomereshortstraightstumps:\"ilmesemblequ’ilyalaunveritablearretdedeveloppementpartiel。\"Ontheotherhand,hedescribesthefemalemothsoftheAndreJeanbreedashaving\"leursaileslargesetetalees。Unseulpresentequelquescourburesirregulieresetdesplisanormaux。\"Asmothsandbutterfliesofallkindsrearedfromwildcaterpillarsunderconfinementoftenhavecrippledwings,thesamecause,whateveritmaybe,hasprobablyactedonsilk—moths,butthedisuseoftheirwingsduringsomanygenerationshas,itmaybesuspected,likewisecomeintoplay。

  Themothsofmanybreedsfailtogluetheireggstothesurfaceonwhichtheyarelaid(8/79。Quatrefages’Etudes’etc。page214。)butthisproceeds,accordingtoCapt。Hutton(8/80。’Transact。Ent。Soc。’utsuprapage151。),merelyfromtheglandsoftheovipositorbeingweakened。

  Aswithotherlong—domesticatedanimals,theinstinctsofthesilk—mothhavesuffered。Thecaterpillars,whenplacedonamulberry—tree,oftencommitthestrangemistakeofdevouringthebaseoftheleafonwhichtheyarefeeding,andconsequentlyfalldown;buttheyarecapable,accordingtoM。Robinet(8/81。’Manueldel’Educateur’etc。page26。)ofagaincrawlingupthetrunk。Eventhiscapacitysometimesfails,forM。Martins(8/82。

  Godron’Del’Espece’page462。)placedsomecaterpillarsonatree,andthosewhichfellwerenotabletoremountandperishedofhunger;theywereevenincapableofpassingfromleaftoleaf。

  Someofthemodificationswhichthesilk—mothhasundergonestandincorrelationwithoneanother。Thus,theeggsofthemothswhichproducewhitecocoonsandofthosewhichproduceyellowcocoonsdifferslightlyintint。Theabdominalfeet,also,ofthecaterpillarswhichyieldwhitecocoonsarealwayswhite,whilstthosewhichgiveyellowcocoonsareinvariablyyellow。(8/83。Quatrefages’Etudes’etc。pages12,209,214。)Wehaveseenthatthecaterpillarswithdarktiger—likestripesproducemothswhicharemoredarklyshadedthanothermoths。Itseemswellestablished(8/84。Robinet’Manuel’etc。page303。)thatinFrancethecaterpillarsoftheraceswhichproducewhitesilk,andcertainblackcaterpillars,haveresisted,betterthanotherraces,thediseasewhichhasrecentlydevastatedthesilk—districts。Lastly,theracesdifferconstitutionally,forsomedonotsucceedsowellunderatemperateclimateasothers;andadampsoildoesnotequallyinjurealltheraces。(8/85。Robinetibidpage15。)]

  Fromthesevariousfactswelearnthatsilk—moths,likethehigheranimals,varygreatlyunderlong—continueddomestication。Welearnalsothemoreimportantfactthatvariationsmayoccuratvariousperiodsoflife,andbeinheritedatacorrespondingperiod。AndfinallyweseethatinsectsareamenabletothegreatprincipleofSelection。

  CHAPTER1。IX。

  CULTIVATEDPLANTS:CEREALANDCULINARYPLANTS。

  PRELIMINARYREMARKSONTHENUMBERANDPARENTAGEOFCULTIVATEDPLANTS。

  FIRSTSTEPSINCULTIVATION。

  GEOGRAPHICALDISTRIBUTIONOFCULTIVATEDPLANTS。

  CEREALIA。

  DOUBTSONTHENUMBEROFSPECIES。

  WHEAT:VARIETIESOF。

  INDIVIDUALVARIABILITY。

  CHANGEDHABITS。

  SELECTION。

  ANCIENTHISTORYOFTHEVARIETIES。

  MAIZE:GREATVARIATIONOF。

  DIRECTACTIONOFCLIMATEON。

  CULINARYPLANTS。

  CABBAGES:VARIETIESOF,INFOLIAGEANDSTEMS,BUTNOTINOTHERPARTS。

  PARENTAGEOF。

  OTHERSPECIESOFBRASSICA。

  PEAS:AMOUNTOFDIFFERENCEINTHESEVERALKINDS,CHIEFLYINTHEPODSAND

  SEED。

  SOMEVARIETIESCONSTANT,SOMEHIGHLYVARIABLE。

  DONOTINTERCROSS。

  BEANS。

  POTATOES:NUMEROUSVARIETIESOF。

  DIFFERINGLITTLEEXCEPTINTHETUBERS。

  CHARACTERSINHERITED。

  Ishallnotenterintosomuchdetailonthevariabilityofcultivatedplants,asinthecaseofdomesticatedanimals。Thesubjectisinvolvedinmuchdifficulty。Botanistshavegenerallyneglectedcultivatedvarieties,asbeneaththeirnotice。Inseveralcasesthewildprototypeisunknownordoubtfullyknown;andinothercasesitishardlypossibletodistinguishbetweenescapedseedlingsandtrulywildplants,sothatthereisnosafestandardofcomparisonbywhichtojudgeofanysupposedamountofchange。

  Notafewbotanistsbelievethatseveralofourancientlycultivatedplantshavebecomesoprofoundlymodifiedthatitisnotpossiblenowtorecognisetheiraboriginalparent—forms。Equallyperplexingarethedoubtswhethersomeofthemaredescendedfromonespecies,orfromseveralinextricablycommingledbycrossingandvariation。Variationsoftenpassinto,andcannotbedistinguishedfrom,monstrosities;andmonstrositiesareoflittlesignificanceforourpurpose。Manyvarietiesarepropagatedsolelybygrafts,buds,layers,bulbs,etc。,andfrequentlyitisnotknownhowfartheirpeculiaritiescanbetransmittedbyseminalgeneration。

  Nevertheless,somefactsofvaluecanbegleaned:andotherfactswillhereafterbeincidentallygiven。Onechiefobjectinthetwofollowingchaptersistoshowhowmanycharactersinourcultivatedplantshavebecomevariable。

  Beforeenteringondetailsafewgeneralremarksontheoriginofcultivatedplantsmaybeintroduced。M。Alph。DeCandolle(9/1。’Geographiebotaniqueraisonnee’1855pages810to991。)inanadmirablediscussiononthissubject,inwhichhedisplaysawonderfulamountofknowledge,givesalistof157ofthemostusefulcultivatedplants。Ofthesehebelievesthat85arealmostcertainlyknownintheirwildstate;butonthisheadothercompetentjudges(9/2。ReviewbyMr。Benthamin’Hort。Journal’volume9

  1855page133entitled’HistoricalNotesoncultivatedPlants’byDr。A。

  Targioni—Tozzetti。Seealso’EdinburghReview’1866page510。)entertaingreatdoubts。Of40ofthem,theoriginisadmittedbyM。DeCandolletobedoubtful,eitherfromacertainamountofdissimilaritywhichtheypresentwhencomparedwiththeirnearestalliesinawildstate,orfromtheprobabilityofthelatternotbeingtrulywildplants,butseedlingsescapedfromculture。Oftheentire157,32alonearerankedbyM。DeCandolleasquiteunknownintheiraboriginalcondition。Butitshouldbeobservedthathedoesnotincludeinhislistseveralplantswhichpresentill—definedcharacters,namely,thevariousformsofpumpkins,millet,sorghum,kidney—bean,dolichos,capsicum,andindigo。Nordoesheincludeflowers;andseveralofthemoreancientlycultivatedflowers,suchascertainroses,thecommonImperiallily,thetuberose,andeventhelilac,aresaid(9/3。’Hist。Notes’asabovebyTargioni—Tozzetti。)nottobeknowninthewildstate。

  Fromtherelativenumbersabovegiven,andfromotherargumentsofmuchweight,M。DeCandolleconcludesthatplantshaverarelybeensomuchmodifiedbyculturethattheycannotbeidentifiedwiththeirwildprototypes。Butonthisview,consideringthatsavagesprobablywouldnothavechosenrareplantsforcultivation,thatusefulplantsaregenerallyconspicuous,andthattheycouldnothavebeentheinhabitantsofdesertsorofremoteandrecentlydiscoveredislands,itappearsstrangetomethatsomanyofourcultivatedplantsshouldbestillunknownoronlydoubtfullyknowninthewildstate。If,ontheotherhand,manyoftheseplantshavebeenprofoundlymodifiedbyculture,thedifficultydisappears。Thedifficultywouldalsoberemovediftheyhavebeenexterminatedduringtheprogressofcivilisation;butM。DeCandollehasshownthatthisprobablyhasseldomoccurred。Assoonasaplantwascultivatedinanycountry,thehalf—civilisedinhabitantswouldnolongerhaveneedtosearchthewholesurfaceofthelandforit,andthusleadtoitsextirpation;andevenifthisdidoccurduringafamine,dormantseedswouldbeleftintheground。

  Intropicalcountriesthewildluxurianceofnature,aswaslongagoremarkedbyHumboldt,overpowersthefeebleeffortsofman。Inancientlycivilisedtemperatecountries,wherethewholefaceofthelandhasbeengreatlychanged,itcanhardlybedoubtedthatsomeplantshavebecomeextinct;neverthelessDeCandollehasshownthatalltheplantshistoricallyknowntohavebeenfirstcultivatedinEuropestillexisthereinthewildstate。

  MM。Loiseleur—Deslongchamps(9/4。’ConsiderationssurlesCereales’1842

  page37。’GeographieBot。’1855page930。\"Plusonsupposel’agricultureancienneetremontantauneepoqued’ignorance,plusilestprobablequelescultivateursavaientchoisidesespecesoffrantal’originememeunavantageincontestable。\")andDeCandollehaveremarkedthatourcultivatedplants,moreespeciallythecereals,mustoriginallyhaveexistedinnearlytheirpresentstate;forotherwisetheywouldnothavebeennoticedandvaluedasobjectsoffood。Buttheseauthorsapparentlyhavenotconsideredthemanyaccountsgivenbytravellersofthewretchedfoodcollectedbysavages。IhavereadanaccountofthesavagesofAustraliacooking,duringadearth,manyvegetablesinvariousways,inthehopesofrenderingtheminnocuousandmorenutritious。Dr。Hookerfoundthehalf—starvedinhabitantsofavillageinSikhimsufferinggreatlyfromhavingeatenarum—roots(9/5。Dr。Hookerhasgivenmethisinformation。Seealsohis’HimalayanJournals’1854volume2page49。),whichtheyhadpoundedandleftforseveraldaystoferment,soaspartiallytodestroytheirpoisonousnature;andheaddsthattheycookedandatemanyotherdeleteriousplants。SirAndrewSmithinformsmethatinSouthAfricaalargenumberoffruitsandsucculentleaves,andespeciallyroots,areusedintimesofscarcity。Thenatives,indeed,knowthepropertiesofalongcatalogueofplants,somehavingbeenfoundduringfaminestobeeatable,othersinjurioustohealth,orevendestructivetolife。HemetapartyofBaquanaswho,havingbeenexpelledbytheconqueringZulus,hadlivedforyearsonanyrootsorleaveswhichaffordedsomelittlenutrimentanddistendedtheirstomachs,soastorelievethepangsofhunger。Theylookedlikewalkingskeletons,andsufferedfearfullyfromconstipation。SirAndrewSmithalsoinformsmethatonsuchoccasionsthenativesobserveasaguideforthemselves,whatthewildanimals,especiallybaboonsandmonkeys,eat。

  Frominnumerableexperimentsmadethroughdirenecessitybythesavagesofeveryland,withtheresultshandeddownbytradition,thenutritious,stimulating,andmedicinalpropertiesofthemostunpromisingplantswereprobablyfirstdiscovered。Itappears,forinstance,atfirstaninexplicablefactthatuntutoredman,inthreedistantquartersoftheworld,shouldhavediscovered,amongstahostofnativeplants,thattheleavesofthetea—plantandmattee,andtheberriesofthecoffee,allincludedastimulatingandnutritiousessence,nowknowntobechemicallythesame。Wecanalsoseethatsavagessufferingfromsevereconstipationwouldnaturallyobservewhetheranyoftherootswhichtheydevouredactedasaperients。Weprobablyoweourknowledgeoftheusesofalmostallplantstomanhavingoriginallyexistedinabarbarousstate,andhavingbeenoftencompelledbyseverewanttotryasfoodalmosteverythingwhichhecouldchewandswallow。

  Fromwhatweknowofthehabitsofsavagesinmanyquartersoftheworld,thereisnoreasontosupposethatourcerealplantsoriginallyexistedintheirpresentstatesovaluabletoman。Letuslooktoonecontinentalone,namely,Africa:Barth(9/6。’TravelsinCentralAfrica’Englishtranslationvolume1pages529and390;volume2pages29,265,270。Livingstone’Travels’page551。)statesthattheslavesoveralargepartofthecentralregionregularlycollecttheseedsofawildgrass,thePennisetumdistichum;inanotherdistricthesawwomencollectingtheseedsofaPoabyswingingasortofbasketthroughtherichmeadow—land。NearTete,Livingstoneobservedthenativescollectingtheseedsofawildgrass,andfarthersouth,asAnderssoninformsme,thenativeslargelyusetheseedofagrassofaboutthesizeofcanary—seed,whichtheyboilinwater。Theyeatalsotherootsofcertainreeds,andeveryonehasreadoftheBushmenprowlingaboutanddiggingupwithafire—hardenedstakevariousroots。

  Similarfactswithrespecttothecollectionofseedsofwildgrassesinotherpartsoftheworldcouldbegiven。(9/7。ForinstanceinbothNorthandSouthAmerica。Mr。Edgeworth’JournalProc。Linn。Soc。’vol6Bot。1862

  page181statesthatinthedesertsofthePunjabpoorwomensweepup,\"byawhiskintostrawbaskets,\"theseedsoffourgeneraofgrasses,namely,ofAgrostis,Panicum,Cenchrus,andPennisetum,aswellastheseedsoffourothergenerabelongingtodistinctfamilies。)

  Accustomedaswearetoourexcellentvegetablesandlusciousfruits,wecanhardlypersuadeourselvesthatthestringyrootsofthewildcarrotandparsnip,orthelittleshootsofthewildasparagus,orcrabs,sloes,etc。,shouldeverhavebeenvalued;yet,fromwhatweknowofthehabitsofAustralianandSouthAfricansavages,weneedfeelnodoubtonthishead。

  TheinhabitantsofSwitzerlandduringtheStone—periodlargelycollectedwildcrabs,sloes,bullaces,hipsofroses,elderberries,beechmast,andotherwildberriesandfruit。(9/8。Prof。O。Heer’DiePflanzenderPfahlbauten’1866ausdemNeujahr。Naturforsch。Geselschaft’1866;andDr。

  H。ChristinRutimeyer’s’DieFaunaderPfahlbauten’1861s。226。)JemmyButton,aFuegianonboardthe’Beagle,’remarkedtomethatthepoorandacidblack—currantsofTierradelFuegoweretoosweetforhistaste。

  Thesavageinhabitantsofeachland,havingfoundoutbymanyandhardtrialswhatplantswereuseful,orcouldberenderedusefulbyvariouscookingprocesses,wouldafteratimetakethefirststepincultivationbyplantingthemneartheirusualabodes。Livingstone(9/9。’Travels’page535。DuChaillu’AdventuresinEquatorialAfrica’1861page445。)statesthatthesavageBatokassometimesleftwildfruit—treesstandingintheirgardens,andoccasionallyevenplantedthem,\"apracticeseennowhereelseamongstthenatives。\"ButDuChaillusawapalmandsomeotherwildfruit—

  treeswhichhadbeenplanted;andthesetreeswereconsideredprivateproperty。Thenextstepincultivation,andthiswouldrequirebutlittleforethought,wouldbetosowtheseedsofusefulplants;andasthesoilnearthehovelsofthenatives(9/10。InTierradelFuegothespotwherewigwamshadformerlystoodcouldbedistinguishedatagreatdistancebythebrightgreentintofthenativevegetation。)wouldoftenbeinsomedegreemanured,improvedvarietieswouldsoonerorlaterarise。Orawildandunusuallygoodvarietyofanativeplantmightattracttheattentionofsomewiseoldsavage;andhewouldtransplantit,orsowitsseed。Thatsuperiorvarietiesofwildfruit—treesoccasionallyarefoundiscertain,asinthecaseoftheAmericanspeciesofhawthorns,plums,cherries,grapes,andhickories,specifiedbyProfessorAsaGray。(9/11。’AmericanAcad。ofArtsandSciences’April10th,1860page413。Downing’TheFruitsofAmerica’1845page261。)Downingalsoreferstocertainwildvarietiesofthehickory,asbeing\"ofmuchlargersizeandfinerflavourthanthecommonspecies。\"IhavereferredtoAmericanfruit—trees,becausewearenotinthiscasetroubledwithdoubtswhetherornotthevarietiesareseedlingswhichhaveescapedfromcultivation。Transplantinganysuperiorvariety,orsowingitsseeds,hardlyimpliesmoreforethoughtthanmightbeexpectedatanearlyandrudeperiodofcivilisation。EventheAustralianbarbarians\"havealawthatnoplantbearingseedsistobedugupafterithasflowered;\"andSirG。Grey(9/12。’JournalsofExpeditionsinAustralia’1841volume2page292。)neversawthislaw,evidentlyframedforthepreservationoftheplant,violated。WeseethesamespiritinthesuperstitiousbeliefoftheFuegians,thatkillingwater—fowlwhilstveryyoungwillbefollowedby\"muchrain,snow,blowmuch。\"(9/13。Darwin’JournalofResearches’1845page215。)Imayadd,asshowingforethoughtinthelowestbarbarians,thattheFuegianswhentheyfindastrandedwhaleburylargeportionsinthesand,andduringtheoften—recurrentfaminestravelfromgreatdistancesfortheremnantsofthehalf—putridmass。

  Ithasoftenbeenremarked(9/14。DeCandollehastabulatedthefactsinthemostinterestingmannerinhis’GeographieBot。’page986。)thatwedonotoweasingleusefulplanttoAustraliaortheCapeofGoodHope,countriesaboundingtoanunparalleleddegreewithendemicspecies,——ortoNewZealand,ortoAmericasouthofthePlata;and,accordingtosomeauthors,nottoAmericanorthwardofMexico。Idonotbelievethatanyedibleorvaluableplant,exceptthecanary—grass,hasbeenderivedfromanoceanicoruninhabitedisland。Ifnearlyallourusefulplants,nativesofEurope;Asia,andSouthAmerica,hadoriginallyexistedintheirpresentcondition,thecompleteabsenceofsimilarlyusefulplantsinthegreatcountriesjustnamedwouldbeindeedasurprisingfact。Butiftheseplantshavebeensogreatlymodifiedandimprovedbycultureasnolongercloselytoresembleanynaturalspecies,wecanunderstandwhytheabove—namedcountrieshavegivenusnousefulplants,fortheywereeitherinhabitedbymenwhodidnotcultivatethegroundatall,asinAustraliaandtheCapeofGoodHope,orwhocultivateditveryimperfectly,asinsomepartsofAmerica。Thesecountriesdoyieldplantswhichareusefultosavageman;

  andDr。Hooker(9/15。’FloraofAustralia’Introductionpage110。)

  enumeratesnolessthan107suchspeciesinAustraliaalone;buttheseplantshavenotbeenimproved,andconsequentlycannotcompetewiththosewhichhavebeencultivatedandimprovedduringthousandsofyearsinthecivilisedworld。

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