Multisvideripoterit，majoremessodifferentiamSimiaeetHominis，quamdieietnoctis；verumtamenhi，comparationeinstitutaintersummosEuropaeHeroesetHottentottosadCaputbonaespeidegentes，difficillimesibipersuadebunt，haseosdemhaberenatales；velsivirginemnobilemaulicam，maximecomtamethumanissimam，conferrevellentcumhominesylvestrietsibirelicto，vixauguraripossent，huncetillamejusdemessespeciei。——’LinnaeiAmoenitatesAcad。
\"Anthropomorpha。\"’
THEquestionofquestionsformankind——theproblemwhichunderliesallothers，andismoredeeplyinterestingthananyother——istheascertainmentoftheplacewhichManoccupiesinnatureandofhisrelationstotheuniverseofthings。Whenceourracehascome；whatarethelimitsofourpowerovernature，andofnature’spoweroverus；towhatgoalwearetending；aretheproblemswhichpresentthemselvesanewandwithundiminishedinteresttoeverymanbornintotheworld。
Mostofus，shrinkingfromthedifficultiesanddangerswhichbesettheseekerafteroriginalanswerstotheseriddles，arecontentedtoignorethemaltogether，ortosmothertheinvestigatingspiritunderthefeatherbedofrespectedandrespectabletradition。But，ineveryage，oneortworestlessspirits，blessedwiththatconstructivegenius，whichcanonlybuildonasecurefoundation，orcursedwiththespiritofmerescepticism，areunabletofollowinthewell-wornandcomfortabletrackoftheirforefathersandcontemporaries，andunmindfulofthornsandstumbling-blocks，strikeoutintopathsoftheirown。Thescepticsendintheinfidelitywhichassertstheproblemtobeinsoluble，orintheatheismwhichdeniestheexistenceofanyorderlyprogressandgovernanceofthings：themenofgeniuspropoundsolutionswhichgrowintosystemsofTheologyorofPhilosophy，orveiledinmusicallanguagewhichsuggestsmorethanitasserts，taketheshapeofthePoetryofanepoch。
Eachsuchanswertothegreatquestion，invariablyassertedbythefollowersofitspropounder，ifnotbyhimself，tobecompleteandfinal，remainsinhighauthorityandesteem，itmaybeforonecentury，oritmaybefortwenty：but，asinvariably，Timeproveseachreplytohavebeenamereapproximationtothetruth——tolerablechieflyonaccountoftheignoranceofthosebywhomitwasaccepted，andwhollyintolerablewhentestedbythelargerknowledgeoftheirsuccessors。
Inawell-wornmetaphor，aparallelisdrawnbetweenthelifeofmanandthemetamorphosisofthecaterpillarintothebutterfly；butthecomparisonmaybemorejustaswellasmorenovel，ifforitsformertermwetakethementalprogressoftherace。Historyshowsthatthehumanmind，fedbyconstantaccessionsofknowledge，periodicallygrowstoolargeforitstheoreticalcoverings，andburststhemasundertoappearinnewhabiliments，asthefeedingandgrowinggrub，atintervals，castsitstoonarrowskinandassumesanother，itselfbuttemporary。TrulytheimagostateofManseemstobeterriblydistant，buteverymoultisastepgained，andofsuchtherehavebeenmany。
Sincetherevivaloflearning，wherebytheWesternracesofEuropewereenabledtoenteruponthatprogresstowardstrueknowledge，whichwascommencedbythephilosophersofGreece，butwasalmostarrestedinsubsequentlongagesofintellectualstagnation，or，atmost，gyration，thehumanlarvahasbeenfeedingvigorously，andmoultinginproportion。
Askinofsomedimensionwascastinthe16thcentury，andanothertowardstheendofthe18th，while，withinthelastfiftyyears，theextraordinarygrowthofeverydepartmentofphysicalsciencehasspreadamongusmentalfoodofsonutritiousandstimulatingacharacterthatanewecdysisseemsimminent。Butthisisaprocessnotunusuallyaccompaniedbymanythroesandsomesicknessanddebility，or，itmaybe，bygraverdisturbances；sothateverygoodcitizenmustfeelboundtofacilitatetheprocess，andevenifhehavenothingbutascalpeltoworkwithal，toeasethecrackingintegumenttothebestofhisability。
Inthisdutyliesmyexcuseforthepublicationoftheseessays。Foritwillbeadmittedthatsomeknowledgeofman’spositionintheanimateworldisanindispensablepreliminarytotheproperunderstandingofhisrelationstotheuniverse——andthisagainresolvesitself，inthelongrun，intoaninquiryintothenatureandtheclosenessofthetieswhichconnecthimwiththosesingularcreatureswhosehistory*hasbeensketchedintheprecedingpages。
[footnote]*Itwillbeunderstoodthat，intheprecedingEssay，Ihaveselectedfornoticefromthevastmassofpaperswhichhavebeenwrittenupontheman-likeApes，onlythosewhichseemtometobeofspecialmoment。
TheimportanceofsuchaninquiryisindeedintuitivelymanifestBroughtfacetofacewiththeseblurredcopiesofhimself，theleastthoughtfulofmenisconsciousofacertainshock，dueperhaps，notsomuchtodisgustattheaspectofwhatlookslikeaninsultingcaricature，astotheawakeningofasuddenandprofoundmistrustoftime-honouredtheoriesandstrongly-rootedprejudicesregardinghisownpositioninnature，andhisrelationstotheunder-worldoflife；whilethatwhichremainsadimsuspicionfortheunthinking，becomesavastargument，fraughtwiththedeepestconsequences，forallwhoareacquaintedwiththerecentprogressoftheanatomicalandphysiologicalsciences。
Inowproposebrieflytounfoldthatargument，andtosetforth，inaformintelligibletothosewhopossessnospecialacquaintancewithanatomicalscience，thechieffactsuponwhichallconclusionsrespectingthenatureandtheextentofthebondswhichconnectmanwiththebruteworldmustbebased：Ishallthenindicatetheoneimmediateconclusionwhich，inmyjudgment，isjustifiedbythosefacts，andI
shallfinallydiscussthebearingofthatconclusionuponthehypotheseswhichhavebeenentertainedrespectingtheOriginofMan。
ThefactstowhichIwouldfirstdirectthereader’sattention，thoughignoredbymanyoftheprofessedinstructorsofthepublicmind，areeasyofdemonstrationandareuniversallyagreedtobymenofscience；
whiletheirsignificanceissogreat，thatwhosohasdulyponderedoverthemwill，Ithink，findlittletostartlehimintheotherrevelationsofBiology。IrefertothosefactswhichhavebeenmadeknownbythestudyofDevelopment。
Itisatruthofverywide，ifnotofuniversal，application，thateverylivingcreaturecommencesitsexistenceunderaformdifferentfrom，andsimplerthan，thatwhichiteventuallyattains。
FIG。12。——A。EggoftheDog，withthevitellinemembraneburst，soastogiveexittotheyolk，thegerminalvesicle（a），anditsincludedspot（b）。B。C。D。EF。Successivechangesoftheyolkindicatedinthetext。AfterBischoff。
Theoakisamorecomplexthingthanthelittlerudimentaryplantcontainedintheacorn；thecaterpillarismorecomplexthantheegg；
thebutterflythanthecaterpillar；andeachofthesebeings，inpassingfromitsrudimentarytoitsperfectcondition，runsthroughaseriesofchanges，thesumofwhichiscalleditsDevelopment。Inthehigheranimalsthesechangesareextremelycomplicated；but，withinthelasthalfcentury，thelaboursofsuchmenasVonBaer，Rathke，Reichert，Bischof，andRemak，havealmostcompletelyunravelledthem，sothatthesuccessivestagesofdevelopmentwhichareexhibitedbyaDog，forexample，arenowaswellknowntotheembryologistasarethestepsofthemetamorphosisofthesilkwormmothtotheschool-boy。Itwillbeusefultoconsiderwithattentionthenatureandtheorderofthestagesofcaninedevelopment，asanexampleoftheprocessinthehigheranimalsgenerally。
TheDog，likeallanimals，savetheverylowest（andfurtherinquiriesmaynotimprobablyremovetheapparentexception），commencesitsexistenceasanegg：asabodywhichis，ineverysense，asmuchaneggasthatofahen，butisdevoidofthataccumulationofnutritivematterwhichconfersuponthebird’seggitsexceptionalsizeanddomesticutility；andwantstheshell，whichwouldnotonlybeuselesstoananimalincubatedwithinthebodyofitsparent，butwouldcutitofffromaccesstothesourceofthatnutrimentwhichtheyoungcreaturerequires，butwhichtheminuteeggofthemammaldoesnotcontainwithinitself。
TheDog’seggis，infact，alittlespheroidalbag（Fig。12），formedofadelicatetransparentmembranecalledthe’vitellinemembrane’，andabout1/130to1/120thofaninchindiameter。Itcontainsamassofviscidnutritivematter——the’yelk’——withinwhichisinclosedasecondmuchmoredelicatespheroidalbag，calledthe’germinalvesicle’（a）。
Inthis，lastly，liesamoresolidroundedbody，termedthe’germinalspot’（b）。
Theegg，or’Ovum，’isoriginallyformedwithinagland，fromwhich，indueseason，itbecomesdetached，andpassesintothelivingchamberfittedforitsprotectionandmaintenanceduringtheprotractedprocessofgestation。Here，whensubjectedtotherequiredconditions，thisminuteandapparentlyinsignificantparticleoflivingmatterbecomesanimatedbyanewandmysteriousactivity。Thegerminalvesicleandspotceasetobediscernible（theirprecisefatebeingoneoftheyetunsolvedproblemsofembryology），buttheyelkbecomescircumferentiallyindented，asifaninvisibleknifehadbeendrawnroundit，andthusappearsdividedintotwohemispheres（Fig。12，C）。
Bytherepetitionofthisprocessinvariousplanes，thesehemispheresbecomesubdivided，sothatfoursegmentsareproduced（D）；andthese，inlikemanner，divideandsubdivideagain，untilthewholeyelkisconvertedintoamassofgranules，eachofwhichconsistsofaminutespheroidofyelk-substance，inclosingacentralparticle，theso-called’nucleus’（F）。Nature，bythisprocess，hasattainedmuchthesameresultasthatatwhichahumanartificerarrivesbyhisoperationsinabrickfield。Shetakestheroughplasticmaterialoftheyelkandbreaksitupintowell-shapedtolerablyeven-sizedmasses，handyforbuildingupintoanypartofthelivingedifice。
FIG。13。——EarliestrudimentoftheDog。B。Rudimentfurtheradvanced，showingthefoundationsofthehead，tail，andvertebralcolumn。C。
Theveryyoungpuppy，withattachedendsoftheyelk-sacandallantois，andinvestedintheamnion。
Next，themassoforganicbricks，or’cells’astheyaretechnicallycalled，thusformed，acquiresanorderlyarrangement，becomingconvertedintoahollowspheroidwithdoublewalls。Then，upononesideofthisspheroid，appearsathickening，and，byandbye，inthecentreoftheareaofthickening，astraightshallowgroove（Fig。13，A）marksthecentrallineoftheedificewhichistoberaised，or，inotherwords，indicatesthepositionofthemiddlelineofthebodyofthefuturedog。Thesubstanceboundingthegrooveoneachsidenextrisesupintoafold，therudimentofthesidewallofthatlongcavity，whichwilleventuallylodgethespinalmarrowandthebrain；
andinthefloorofthischamberappearsasolidcellularcord，theso-called’notochord。’Oneendoftheinclosedcavitydilatestoformthehead（Fig。13，B），theotherremainsnarrow，andeventuallybecomesthetail；thesidewallsofthebodyarefashionedoutofthedownwardcontinuationofthewallsofthegroove；andfromthem，byandbye，growoutlittlebudswhich，bydegrees，assumetheshapeoflimbs。
Watchingthefashioningprocessstagebystage，oneisforciblyremindedofthemodellerinclay。Everypart，everyorgan，isatfirst，asitwere，pincheduprudely，andsketchedoutintherough；
thenshapedmoreaccurately；andonly，atlast，receivesthetoucheswhichstampitsfinalcharacter。
Thus，atlength，theyoungpuppyassumessuchaformasisshowninFig。
13，C。Inthisconditionithasadisproportionatelylargehead，asdissimilartothatofadogasthebud-likelimbsareunlikehislegs。
Theremainsoftheyelk，whichhavenotyetbeenappliedtothenutritionandgrowthoftheyounganimal，arecontainedinasacattachedtotherudimentaryintestine，andtermedtheyelksac，or’umbilicalvesicle。’Twomembranousbags，intendedtosubserverespectivelytheprotectionandnutritionoftheyoungcreature，havebeendevelopedfromtheskinandfromtheunderandhindersurfaceofthebody；theformer，theso-called’amnion，’isasacfilledwithfluid，whichinveststhewholebodyoftheembryo，andplaysthepartofasortofwater-bedforit；theother，termedthe’allantois，’growsout，loadedwithblood-vessels，fromtheventralregion，andeventuallyapplyingitselftothewallsofthecavity，inwhichthedevelopingorganismiscontained，enablesthesevesselstobecomethechannelbywhichthestreamofnutriment，requiredtosupplythewantsoftheoffspring，isfurnishedtoitbytheparent。
Thestructurewhichisdevelopedbytheinterlacementofthevesselsoftheoffspringwiththoseoftheparent，andbymeansofwhichtheformerisenabledtoreceivenourishmentandtogetridofeffetematters，istermedthe’Placenta。’
Itwouldbetedious，anditisunnecessaryformypresentpurpose，totracetheprocessofdevelopmentfurther；sufficeittosay，that，byalongandgradualseriesofchanges，therudimentheredepictedanddescribedbecomesapuppy，isborn，andthen，bystillslowerandlessperceptiblesteps，passesintotheadultDog。
ThereisnotmuchapparentresemblancebetweenabarndoorFowlandtheDogwhoprotectsthefarm-yard。Neverthelessthestudentofdevelopmentfinds，notonlythatthechickcommencesitsexistenceasanegg，primarilyidentical，inallessentialrespects，withthatoftheDog，butthattheyelkofthiseggundergoesdivision——thattheprimitivegroovearises，andthatthecontiguouspartsofthegermarefashioned，bypreciselysimilarmethods，intoayoungchick，which，atonestageofitsexistence，issolikethenascentDog，thatordinaryinspectionwouldhardlydistinguishthetwo。
Thehistoryofthedevelopmentofanyothervertebrateanimal，Lizard，Snake，Frog，orFish，tellsthesamestory。Thereisalways，tobeginwith，anegghavingthesameessentialstructureasthatoftheDog：——theyelkofthateggalwaysundergoesdivision，or’segmentation’
asitisoftencalled：theultimateproductsofthatsegmentationconstitutethebuildingmaterialsforthebodyoftheyounganimal；andthisisbuiltuproundaprimitivegroove，inthefloorofwhichanotochordisdeveloped。Furthermore，thereisaperiodinwhichtheyoungofalltheseanimalsresembleoneanother，notmerelyinoutwardform，butinallessentialsofstructure，soclosely，thatthedifferencesbetweenthemareinconsiderable，while，intheirsubsequentcourse，theydivergemoreandmorewidelyfromoneanother。Anditisagenerallaw，that，themorecloselyanyanimalsresembleoneanotherinadultstructure，thelongerandthemoreintimatelydotheirembryosresembleoneanother：sothat，forexample，theembryosofaSnakeandofaLizardremainlikeoneanotherlongerthandothoseofaSnakeandofaBird；andtheembryoofaDogandofaCatremainlikeoneanotherforafarlongerperiodthandothoseofaDogandaBird；orofaDogandanOpossum；oreventhanthoseofaDogandaMonkey。
Thusthestudyofdevelopmentaffordsacleartestofclosenessofstructuralaffinity，andoneturnswithimpatiencetoinquirewhatresultsareyieldedbythestudyofthedevelopmentofMan。Ishesomethingapart？DoesheoriginateinatotallydifferentwayfromDog，Bird，Frog，andFish，thusjustifyingthosewhoasserthimtohavenoplaceinnatureandnorealaffinitywiththelowerworldofanimallife？Ordoesheoriginateinasimilargerm，passthroughthesameslowandgraduallyprogressivemodifications，——dependonthesamecontrivancesforprotectionandnutrition，andfinallyentertheworldbythehelpofthesamemechanism？Thereplyisnotdoubtfulforamoment，andhasnotbeendoubtfulanytimethesethirtyyears。Withoutquestion，themodeoforiginandtheearlystagesofthedevelopmentofmanareidenticalwiththoseoftheanimalsimmediatelybelowhiminthescale：——withoutadoubt，intheserespects，heisfarnearertheApes，thantheApesaretotheDog。
TheHumanovumisaboutl/125ofaninchindiameter，andmightbedescribedinthesametermsasthatoftheDog，sothatIneedonlyrefertothefigureillustrative（14A）ofitsstructure。Itleavestheorganinwhichitisformedinasimilarfashionandenterstheorganicchamberpreparedforitsreceptioninthesameway，theconditionsofitsdevelopmentbeinginallrespectsthesame。Ithasnotyetbeenpossible（andonlybysomerarechancecaniteverbepossible）tostudythehumanovuminsoearlyadevelopmentalstageasthatofyelkdivision，butthereiseveryreasontoconcludethatthechangesitundergoesareidenticalwiththoseexhibitedbytheovaofothervertebratedanimals；fortheformativematerialsofwhichtherudimentaryhumanbodyiscomposed，intheearliestconditionsinwhichithasbeenobserved，arethesameasthoseofotheranimals。Someoftheseearlieststagesarefiguredbelow，and，aswillbeseen，theyarestrictlycomparabletotheveryearlystatesoftheDog；themarvellouscorrespondencebetweenthetwowhichiskeptup，evenforsometime，asdevelopmentadvances，becomingapparentbythesimplecomparisonofthefigureswiththoseonpage249。
Fig。14。——A。Humanovum（afterKolliker）。a。germinalvesicle。b。
germinalspot。B。AveryearlyconditionofMan，withyelk-sac，allantois，andamnion（original）。C。Amoreadvancedstage（afterKolliker），compareFig。13，C。
Indeed，itisverylongbeforethebodyoftheyounghumanbeingcanbereadilydiscriminatedfromthatoftheyoungpuppy；but，atatolerablyearlyperiod，thetwobecomedistinguishablebythedifferentformoftheiradjuncts，theyelk-sacandtheallantois。Theformer，intheDog，becomeslongandspindle-shaped，whileinManitremainsspherical；thelatter，intheDog，attainsanextremelylargesize，andthevascularprocesseswhicharedevelopedfromitandeventuallygiverisetotheformationoftheplacenta（takingroot，asitwere，intheparentalorganism，soastodrawnourishmenttherefrom，astherootofatreeextractsitfromthesoil）arearrangedinanencirclingzone，whileinMan，theallantoisremainscomparativelysmall，anditsvascularrootletsareeventuallyrestrictedtoonedisk-likespot。
Hence，whiletheplacentaoftheDogislikeagirdle，thatofManhasthecake-likeform，indicatedbythenameoftheorgan。
But，exactlyinthoserespectsinwhichthedevelopingMandiffersfromtheDog，heresemblestheape，which，likeman，hasaspheroidalyelk-sacandadiscoidal——sometimespartiallylobed——placenta。Sothatitisonlyquiteinthelaterstagesofdevelopmentthattheyounghumanbeingpresentsmarkeddifferencesfromtheyoungape，whilethelatterdepartsasmuchfromthedoginitsdevelopment，asthemandoes。
Startlingasthelastassertionmayappeartobe，itisdemonstrablytrue，anditaloneappearstomesufficienttoplacebeyondalldoubtthestructuralunityofmanwiththerestoftheanimalworld，andmoreparticularlyandcloselywiththeapes。
Thus，identicalinthephysicalprocessesbywhichheoriginates——identicalintheearlystagesofhisformation——identicalinthemodeofhisnutritionbeforeandafterbirth，withtheanimalswhichlieimmediatelybelowhiminthescale——Man，ifhisadultandperfectstructurebecomparedwiththeirs，exhibits，asmightbeexpected，amarvellouslikenessoforganization。Heresemblesthemastheyresembleoneanother——hediffersfromthemastheydifferfromoneanother。——And，thoughthesedifferencesandresemblancescannotbeweighedandmeasured，theirvaluemaybereadilyestimated；thescaleorstandardofjudgment，touchingthatvalue，beingaffordedandexpressedbythesystemofclassificationofanimalsnowcurrentamongzoologists。
Acarefulstudyoftheresemblancesanddifferencespresentedbyanimalshas，infact，lednaturaliststoarrangethemintogroups，orassemblages，allthemembersofeachgrouppresentingacertainamountofdefinableresemblance，andthenumberofpointsofsimilaritybeingsmallerasthegroupislargerand’viceversa’。Thus，allcreatureswhichagreeonlyinpresentingthefewdistinctivemarksofanimalityformthe’Kingdom’ANIMALIA。ThenumerousanimalswhichagreeonlyinpossessingthespecialcharactersofVertebratesformone’Sub-Kingdom’
ofthisKingdom。ThentheSub-kingdomVERTEBRATAissubdividedintothefive’Classes，’Fishes，Amphibians，Reptiles，Birds，andMammals，andtheseintosmallergroupscalled’Orders’；theseinto’Families’
and’Genera’；whilethelastarefinallybrokenupintothesmallestassemblages，whicharedistinguishedbythepossessionofconstant，not-sexual，characters。TheseultimategroupsareSpecies。
Everyyeartendstobringaboutagreateruniformityofopinionthroughoutthezoologicalworldastothelimitsandcharactersofthesegroups，greatandsmall。Atpresent，forexample，noonehastheleastdoubtregardingthecharactersoftheclassesMammalia，Aves，orReptilia；nordoesthequestionarisewhetheranythoroughlywell-knownanimalshouldbeplacedinoneclassortheother。Again，thereisaverygeneralagreementrespectingthecharactersandlimitsoftheordersofMammals，andastotheanimalswhicharestructurallynecessitatedtotakeaplaceinoneoranotherorder。
Noonedoubts，forexample，thattheSlothandtheAnt-eater，theKangarooandtheOpossum，theTigerandtheBadger，theTapirandtheRhinoceros，arerespectivelymembersofthesameorders。Thesesuccessivepairsofanimalsmay，andsomedo，differfromoneanotherimmensely，insuchmattersastheproportionsandstructureoftheirlimbs；thenumberoftheirdorsalandlumbarvertebrae；theadaptationoftheirframestoclimbing，leaping，orrunning；thenumberandformoftheirteeth；andthecharactersoftheirskullsandofthecontainedbrain。But，withallthesedifferences，theyaresocloselyconnectedinallthemoreimportantandfundamentalcharactersoftheirorganization，andsodistinctlyseparatedbythesesamecharactersfromotheranimals，thatzoologistsfinditnecessarytogroupthemtogetherasmembersofoneorder。Andifanynewanimalwerediscovered，andwerefoundtopresentnogreaterdifferencefromtheKangarooandtheOpossum，forexample，thantheseanimalsdofromoneanother，thezoologistwouldnotonlybelogicallycompelledtorankitinthesameorderwiththese，buthewouldnotthinkofdoingotherwise。
Bearingthisobviouscourseofzoologicalreasoninginmind，letusendeavourforamomenttodisconnectourthinkingselvesfromthemaskofhumanity；letusimagineourselvesscientificSaturnians，ifyouwill，fairlyacquaintedwithsuchanimalsasnowinhabittheEarth，andemployedindiscussingtherelationstheybeartoanewandsingular’erectandfeatherlessbiped，’whichsomeenterprisingtraveller，overcomingthedifficultiesofspaceandgravitation，hasbroughtfromthatdistantplanetforourinspection，wellpreserved，maybe，inacaskofrum。Weshouldall，atonce，agreeuponplacinghimamongthemammalianvertebrates；andhislowerjaw，hismolars，andhisbrain，wouldleavenoroomfordoubtingthesystematicpositionofthenewgenusamongthosemammals，whoseyoungarenourishedduringgestationbymeansofaplacenta，orwhatarecalledthe’placentalmammals。’
Further，themostsuperficialstudywouldatonceconvinceusthat，amongtheordersofplacentalmammals，neithertheWhales，northehoofedcreatures，northeSlothsandAnt-eaters，northecarnivorousCats，Dogs，andBears，stilllesstheRodentRatsandRabbits，ortheInsectivorousMolesandHedgehogs，ortheBats，couldclaimour’Homo’，asoneofthemselves。
Therewouldremainthen，butoneorderforcomparison，thatoftheApes（usingthatwordinitsbroadestsense），andthequestionfordiscussionwouldnarrowitselftothis——isMansodifferentfromanyoftheseApesthathemustformanorderbyhimself？Ordoeshedifferlessfromthemthantheydifferfromoneanother，andhencemusttakehisplaceinthesameorderwiththem？
Beinghappilyfreefromallreal，orimaginary，personalinterestintheresultsoftheinquirythussetafoot，weshouldproceedtoweightheargumentsononesideandontheother，withasmuchjudicialcalmnessasifthequestionrelatedtoanewOpossum。Weshouldendeavourtoascertain，withoutseekingeithertomagnifyordiminishthem，allthecharactersbywhichournewMammaldifferedfromtheApes；andifwefoundthatthesewereoflessstructuralvalue，thanthosewhichdistinguishcertainmembersoftheApeorderfromothersuniversallyadmittedtobeofthesameorder，weshouldundoubtedlyplacethenewlydiscoveredtelluriangenuswiththem。
Inowproceedtodetailthefactswhichseemtometoleaveusnochoicebuttoadoptthelastmentionedcourse。
ItisquitecertainthattheApewhichmostnearlyapproachesman，inthetotalityofitsorganization，iseithertheChimpanzeeortheGorilla；andasitmakesnopracticaldifference，forthepurposesofmypresentargument，whichisselectedforcomparison，ontheonehand，withMan，andontheotherhand，withtherestofthePrimates，*Ishallselectthelatter（sofarasitsorganizationisknown）——asabrutenowsocelebratedinproseandverse，thatallmusthaveheardofhim，andhaveformedsomeconceptionofhisappearance。Ishalltakeupasmanyofthemostimportantpointsofdifferencebetweenmanandthisremarkablecreature，asthespaceatmydisposalwillallowmetodiscuss，andthenecessitiesoftheargumentdemand；andIshallinquireintothevalueandmagnitudeofthesedifferences，whenplacedsidebysidewiththosewhichseparatetheGorillafromotheranimalsofthesameorder。
[Footnote]*WearenotatpresentthoroughlyacquaintedwiththebrainoftheGorilla，andtherefore，indiscussingcerebralcharacters，IshalltakethatoftheChimpanzeeasmyhighesttermamongtheApes。
InthegeneralproportionsofthebodyandlimbsthereisaremarkabledifferencebetweentheGorillaandMan，whichatoncestrikestheeye。
TheGorilla’sbrain-caseissmaller，itstrunklarger，itslowerlimbsshorter，itsupperlimbslongerinproportionthanthoseofMan。
Ifindthatthevertebralcolumnofafull-grownGorilla，intheMuseumoftheRoyalCollegeofSurgeons，measures27inchesalongitsanteriorcurvature，fromtheupperedgeoftheatlas，orfirstvertebraoftheneck，tothelowerextremityofthesacrum；thatthearm，withoutthehand，is31-1/2incheslong；thattheleg，withoutthefoot，is26-1/2
incheslong；thatthehandis9-3/4incheslong；thefoot11-1/4incheslong。
Inotherwords，takingthelengthofthespinalcolumnas100，thearmequals115，theleg96，thehand36，andthefoot41。
IntheskeletonofamaleBosjesman，inthesamecollection，theproportions，bythesamemeasurement，tothespinalcolumn，takenas100，are——thearm78，theleg110，thehand26，andthefoot32。Inawomanofthesameracethearmis83，andtheleg120，thehandandfootremainingthesame。InaEuropeanskeletonIfindthearmtobe80，theleg117，thehand26，thefoot35。
Thusthelegisnotsodifferentasitlooksatfirstsight，initsproportiontothespineintheGorillaandintheMan——beingveryslightlyshorterthanthespineintheformer，andbetween1/10and1/5
longerthanthespineinthelatter。ThefootislongerandthehandmuchlongerintheGorilla；butthegreatdifferenceiscausedbythearms，whichareverymuchlongerthanthespineintheGorilla，verymuchshorterthanthespineintheMan。
ThequestionnowariseshowaretheotherApesrelatedtotheGorillaintheserespects——takingthelengthofthespine，measuredinthesameway，at100。InanadultChimpanzee，thearmisonly96，theleg90，thehand43，thefoot39——sothatthehandandthelegdepartmorefromthehumanproportionandthearmless，whilethefootisaboutthesameasintheGorilla。
IntheOrang，thearmsareverymuchlongerthanintheGorilla（122），whilethelegsareshorter（88）；thefootislongerthanthehand（52
and48），andbotharemuchlongerinproportiontothespine。
Intheotherman-likeApesagain，theGibbons，theseproportionsarestillfurtheraltered；thelengthofthearmsbeingtothatofthespinalcolumnas19to11；whilethelegsarealsoathirdlongerthanthespinalcolumn，soastobelongerthaninMan，insteadofshorter。
Thehandishalfaslongasthespinalcolumn，andthefoot，shorterthanthehand，isabout5/11thsofthelengthofthespinalcolumn。
Thus’Hylobates’isasmuchlongerinthearmsthantheGorilla，astheGorillaislongerinthearmsthanMan；while，ontheotherhand，itisasmuchlongerinthelegsthantheMan，astheManislongerinthelegsthantheGorilla，sothatitcontainswithinitselftheextremestdeviationsfromtheaveragelengthofbothpairsoflimbs（Seetheillustrationonpage196）。
TheMandrillpresentsamiddlecondition，thearmsandlegsbeingnearlyequalinlength，andbothbeingshorterthanthespinalcolumn；whilehandandfoothavenearlythesameproportionstooneanotherandtothespine，asinMan。
IntheSpidermonkey（’Ateles’）thelegislongerthanthespine，andthearmthantheleg；and，finally，inthatremarkableLemurineform，theIndri（’Lichanotus’），thelegisaboutaslongasthespinalcolumn，whilethearmisnotmorethan11/18ofitslength；thehandhavingratherlessandthefootrathermore，thanone-thirdthelengthofthespinalcolumn。
Theseexamplesmightbegreatlymultiplied，buttheysufficetoshowthat，inwhateverproportionofitslimbstheGorilladiffersfromMan，theotherApesdepartstillmorewidelyfromtheGorillaandthat，consequently，suchdifferencesofproportioncanhavenoordinalvalue。
Wemaynextconsiderthedifferencespresentedbythetrunk，consistingofthevertebralcolumn，orbackbone，andtheribsandpelvis，orbonyhip-basin，whichareconnectedwithit，inManandintheGorillarespectively。
InMan，inconsequencepartlyofthedispositionofthearticularsurfacesofthevertebrae，andlargelyoftheelastictensionofsomeofthefibrousbands，orligaments，whichconnectthesevertebraetogether，thespinalcolumn，asawhole，hasanelegantS-likecurvature，beingconvexforwardsintheneck，concaveintheback，convexintheloins，orlumbarregion，andconcaveagaininthesacralregion；anarrangementwhichgivesmuchelasticitytothewholebackbone，anddiminishesthejarcommunicatedtothespine，andthroughittothehead，bylocomotionintheerectposition。
Furthermore，underordinarycircumstances，Manhassevenvertebraeinhisneck，whicharecalled’cervical’；twelvesucceedthese，bearingribsandformingtheupperpartoftheback，whencetheyaretermed’dorsal’；fivelieintheloins，bearingnodistinct，orfree，ribs，andarecalled’lumbar’；five，unitedtogetherintoagreatbone，excavatedinfront，solidlywedgedinbetweenthehipbones，toformthebackofthepelvis，andknownbythenameofthe’sacrum’，succeedthese；andfinally，threeorfourlittlemoreorlessmovablebones，sosmallastobeinsignificant，constitutethe’coccyx’orrudimentarytail。
IntheGorilla，thevertebralcolumnissimilarlydividedintocervical，dorsal，lumbar，sacral，andcoccygealvertebrae，andthetotalnumberofcervicalanddorsalvertebrae，takentogether，isthesameasinMan；butthedevelopmentofapairofribstothefirstlumbarvertebra，whichisanexceptionaloccurrenceinMan，istheruleintheGorilla；
andhence，aslumbararedistinguishedfromdorsalvertebraeonlybythepresenceorabsenceoffreeribs，theseventeen\"dorso-lumbar\"
vertebraeoftheGorillaaredividedintothirteendorsalandfourlumbar，whileinMantheyaretwelvedorsalandfivelumbar。
FIG。15。——FrontandsideviewsofthebonypelvisofMan，theGorillaandGibbon：reducedfromdrawingsmadefromnature，ofthesameabsolutelength，byMr。WaterhouseHawkins。
Notonly，however，doesManoccasionallypossessthirteenpairofribs，*
buttheGorillasometimeshasfourteenpairs，whileanOrang-UtanskeletonintheMuseumoftheRoyalCollegeofSurgeonshastwelvedorsalandfivelumbarvertebrae，asinMan。Cuviernotesthesamenumberina’Hylobates’。Ontheotherhand，amongthelowerApes，manypossesstwelvedorsalandsixorsevenlumbarvertebrae；theDouroucoulihasfourteendorsalandeightlumbar，andaLemur（’Stenopstardigradus’）hasfifteendorsalandninelumbarvertebrae。
[Footnote]*\"Morethanonce，\"saysPeterCamper，\"haveImetwithmorethansixlumbarvertebraeinman……OnceI
foundthirteenribsandfourlumbarvertebrae。\"Fallopiusnotedthirteenpairofribsandonlyfourlumbarvertebrae；
andEustachiusoncefoundelevendorsalvertebraeandsixlumbarvertebrae。——’OeuvresdePierreCamper’，T。1，p。
42。AsTysonstates，his’Pygmie’hadthirteenpairofribsandfivelumbarvertebrae。ThequestionofthecurvesofthespinalcolumnintheApesrequiresfurtherinvestigation。
ThevertebralcolumnoftheGorilla，asawhole，differsfromthatofManinthelessmarkedcharacterofitscurves，especiallyintheslighterconvexityofthelumbarregion。Nevertheless，thecurvesarepresent，andarequiteobviousinyoungskeletonsoftheGorillaandChimpanzeewhichhavebeenpreparedwithoutremovaloftheligaments。
InyoungOrangssimilarlypreserved，ontheotherhand，thespinalcolumniseitherstraight，orevenconcaveforwards，throughoutthelumbarregion。
Whetherwetakethesecharactersthen，orsuchminoronesasthosewhicharederivablefromtheproportionallengthofthespinesofthecervicalvertebrae，andthelike，thereisnodoubtwhatsoeverastothemarkeddifferencebetweenManandtheGorilla；butthereisaslittle，thatequallymarkeddifferences，oftheverysameorder，obtainbetweentheGorillaandthelowerApes。
ThePelvis，orbonygirdleofthehips，ofManisastrikinglyhumanpartofhisorganization；theexpandedhaunchbonesaffordingsupportforhisvisceraduringhishabituallyerectposture，andgivingspacefortheattachmentofthegreatmuscleswhichenablehimtoassumeandtopreservethatattitude。IntheserespectsthepelvisoftheGorilladiffersveryconsiderablyfromhis（Fig。15）。ButgonolowerthantheGibbon，andseehowvastlymorehediffersfromtheGorillathanthelatterdoesfromMan，eveninthisstructure。Lookattheflat，narrowhaunchbones——thelongandnarrowpassage——thecoarse，outwardlycurved，ischiaticprominencesonwhichtheGibbonhabituallyrests，andwhicharecoatedbytheso-called\"callosities，\"densepatchesofskin，whollyabsentintheGorilla，intheChimpanzee，andintheOrang，asinMan！
InthelowerMonkeysandintheLemursthedifferencebecomesmorestrikingstill，thepelvisacquiringanaltogetherquadrupedalcharacter。
Butnowletusturntoanoblerandmorecharacteristicorgan——thatbywhichthehumanframeseemstobe，andindeedis，sostronglydistinguishedfromallothers，——Imeantheskull。ThedifferencesbetweenaGorilla’sskullandaMan’saretrulyimmense（Fig。16）。Intheformer，theface，formedlargelybythemassivejaw-bones，predominatesoverthebraincase，orcraniumproper：inthelatter，theproportionsofthetwoarereversed。IntheMan，theoccipitalforamen，throughwhichpassesthegreatnervouscordconnectingthebrainwiththenervesofthebody，isplacedjustbehindthecentreofthebaseoftheskull，whichthusbecomesevenlybalancedintheerectposture；intheGorilla，itliesintheposteriorthirdofthatbase。
IntheMan，thesurfaceoftheskulliscomparativelysmooth，andthesupraciliaryridgesorbrowprominencesusuallyprojectbutlittle——while，intheGorilla，vastcrestsaredevelopedupontheskull，andthebrowridgesoverhang，thecavernousorbits，likegreatpenthouses。
Sectionsoftheskulls，however，showthatsomeoftheapparentdefectsoftheGorilla’scraniumarise，infact，notsomuchfromdeficiencyofbraincaseasfromexcessivedevelopmentofthepartsoftheface。Thecranialcavityisnotill-shaped，andtheforeheadisnottrulyflattenedorveryretreating，itsreallywell-formedcurvebeingsimplydisguisedbythemassofbonewhichisbuiltupagainstit（Fig。16）。
Buttheroofsoftheorbitsrisemoreobliquelyintothecranialcavity，thusdiminishingthespaceforthelowerpartoftheanteriorlobesofthebrain，andtheabsolutecapacityofthecraniumisfarlessthanthatofMan。SofarasIamaware，nohumancraniumbelongingtoanadultmanhasyetbeenobservedwithalesscubicalcapacitythan62
cubicinches，thesmallestcraniumobservedinanyraceofmenbyMorton，measuring63cubicinches；while，ontheotherhand，themostcapaciousGorillaskullyetmeasuredhasacontentofnotmorethan34-1/2cubicinches。Letusassume，forsimplicity’ssake，thatthelowestMan’sskullhastwicethecapacityofthatofthehighestGorilla。*
[Footnote]*IthasbeenaffirmedthatHindoocraniasometimescontainaslittleas27ouncesofwater，whichwouldgiveacapacityofabout46cubicinches。TheminimumcapacitywhichIhaveassumedabove，however，isbaseduponthevaluabletablespublishedbyProfessorR。Wagnerinhis\"VorstudienzueinerwissenschaftlichenMorphologieundPhysiologiedesmenschlichenGehirns。\"Astheresultofthecarefulweighingofmorethan900humanbrains，ProfessorWagnerstatesthatone-halfweighedbetween1200and1400
grammes，andthatabouttwo-ninths，consistingforthemostpartofmalebrains，exceed1400grammes。Thelightestbrainofanadultmale，withsoundmentalfaculties，recordedbyWagner，weighed1020grammes。Asagrammeequals15。4grains，andacubicinchofwatercontains252。4