Thishabit,accordingtoM。A。d’Orbigny,iscommontoallthespeciesofthegenus;itisveryusefultothePeruvianIndians,whousethedungforfuel,andarethussavedthetroubleofcollectingit。
Theguanacosappeartohavefavouritespotsforlyingdowntodie。OnthebanksoftheSt。Cruz,incertaincircumscribedspaces,whichweregenerallybushyandallneartheriver,thegroundwasactuallywhitewithbones。OnonesuchspotIcountedbetweentenandtwentyheads。Iparticularlyexaminedthebones;theydidnotappear,assomescatteredoneswhichI
hadseen,gnawedorbroken,asifdraggedtogetherbybeastsofprey。Theanimalsinmostcasesmusthavecrawled,beforedying,beneathandamongstthebushes。Mr。BynoeinformsmethatduringaformervoyageheobservedthesamecircumstanceonthebanksoftheRioGallegos。Idonotatallunderstandthereasonofthis,butImayobserve,thatthewoundedguanacosattheSt。Cruzinvariablywalkedtowardstheriver。AtSt。JagointheCapedeVerdIslands,Irememberhavingseeninaravinearetiredcornercoveredwithbonesofthegoat;weatthetimeexclaimedthatitwastheburialgroundofallthegoatsintheisland。Imentionthesetriflingcircumstances,becauseincertaincasestheymightexplaintheoccurrenceofanumberofuninjuredbonesinacave,orburiedunderalluvialaccumulations;
andlikewisethecausewhycertainanimalsaremorecommonlyembeddedthanothersinsedimentarydeposits。
OnedaytheyawlwassentunderthecommandofMr。Chafferswiththreedays’provisionstosurveytheupperpartoftheharbour。Inthemorningwesearchedforsomewatering-placesmentionedinanoldSpanishchart。
Wefoundonecreek,attheheadofwhichtherewasatricklingrillthefirstwehadseenofbrackishwater。Herethetidecompelledustowaitseveralhours;andintheintervalIwalkedsomemilesintotheinterior。
Theplainasusualconsistedofgravel,mingledwithsoilresemblingchalkinappearance,butverydifferentfromitinnature。Fromthesoftnessofthesematerialsitwaswornintomanygulleys。Therewasnotatree,and,exceptingtheguanaco,whichstoodonthehill-topawatchfulsentineloveritsherd,scarcelyananimalorabird。Allwasstillnessanddesolation。
Yetinpassingoverthesescenes,withoutonebrightobjectnear,anill-definedbutstrongsenseofpleasureisvividlyexcited。Oneaskedhowmanyagestheplainhadthuslasted,andhowmanymoreitwasdoomedthustocontinue。
“Nonecanreply——allseemseternalnow。Thewildernesshasamysterioustongue,Whichteachesawfuldoubt。”[11]
Intheeveningwesailedafewmilesfurtherup,andthenpitchedthetentsforthenight。Bythemiddleofthenextdaytheyawlwasaground,andfromtheshoalnessofthewatercouldnotproceedanyhigher。Thewaterbeingfoundpartlyfresh,Mr。Chafferstookthedingeyandwentuptwoorthreemilesfurther,whereshealsogrounded,butinafresh-waterriver。
Thewaterwasmuddy,andthoughthestreamwasmostinsignificantinsize,itwouldbedifficulttoaccountforitsorigin,exceptfromthemeltingsnowontheCordillera。Atthespotwherewebivouacked,weweresurroundedbyboldcliffsandsteeppinnaclesofporphyry。IdonotthinkIeversawaspotwhichappearedmoresecludedfromtherestoftheworld,thanthisrockycreviceinthewideplain。
Theseconddayafterourreturntotheanchorage,apartyofofficersandmyselfwenttoransackanoldIndiangrave,whichIhadfoundonthesummitofaneighbouringhill。Twoimmensestones,eachprobablyweighingatleastacoupleoftons,hadbeenplacedinfrontofaledgeofrockaboutsixfeethigh。Atthebottomofthegraveonthehardrocktherewasalayerofearthaboutafootdeep,whichmusthavebeenbroughtupfromtheplainbelow。Aboveitapavementofflatstoneswasplaced,onwhichotherswerepiled,soastofillupthespacebetweentheledgeandthetwogreatblocks。Tocompletethegrave,theIndianshadcontrivedtodetachfromtheledgeahugefragment,andtothrowitoverthepilesoastorestonthetwoblocks。Weunderminedthegraveonbothsides,butcouldnotfindanyrelics,orevenbones。Thelatterprobablyhaddecayedlongsinceinwhichcasethegravemusthavebeenofextremeantiquity,forIfoundinanotherplacesomesmallerheapsbeneathwhichaveryfewcrumblingfragmentscouldyetbedistinguishedashavingbelongedtoaman。Falconerstates,thatwhereanIndiandiesheisburied,butthatsubsequentlyhisbonesarecarefullytakenupandcarried,letthedistancebeeversogreat,tobedepositednearthesea-coast。Thiscustom,Ithink,maybeaccountedforbyrecollecting,thatbeforetheintroductionofhorses,theseIndiansmusthavelednearlythesamelifeastheFuegiansnowdo,andthereforegenerallyhaveresidedintheneighbourhoodofthesea。Thecommonprejudiceoflyingwhereone’sancestorshavelain,wouldmakethenowroamingIndiansbringthelessperishablepartoftheirdeadtotheirancientburial-groundonthecoast。
January9th,1834——BeforeitwasdarktheBeagleanchoredinthefinespaciousharbourofPortSt。Julian,situatedaboutonehundredandtenmilestothesouthofPortDesire。Weremainedhereeightdays。ThecountryisnearlysimilartothatofPortDesire,butperhapsrathermoresterile。OnedayapartyaccompaniedCaptainFitzRoyonalongwalkroundtheheadoftheharbour。Wewereelevenhourswithouttastinganywater,andsomeofthepartywerequiteexhausted。FromthesummitofahillsincewellnamedThirstyHillafinelakewasspied,andtwoofthepartyproceededwithconcertedsignalstoshowwhetheritwasfreshwater。Whatwasourdisappointmenttofindasnow-whiteexpanseofsalt,crystallizedingreatcubes!Weattributedourextremethirsttothedrynessoftheatmosphere;
butwhateverthecausemightbe,wewereexceedinglygladlateintheeveningtogetbacktotheboats。Althoughwecouldnowherefind,duringourwholevisit,asingledropoffreshwater,yetsomemustexist;forbyanoddchanceIfoundonthesurfaceofthesaltwater,neartheheadofthebay,aColymbetesnotquitedead,whichmusthavelivedinsomenotfardistantpool。ThreeotherinsectsaCincindela,likehybrida,aCymindis,andaHarpalus,whichallliveonmuddyflatsoccasionallyoverflowedbythesea,andoneotherfounddeadontheplain,completethelistofthebeetles。
Agood-sizedflyTabanuswasextremelynumerous,andtormentedusbyitspainfulbite。Thecommonhorsefly,whichissotroublesomeintheshadylanesofEngland,belongstothissamegenus。Weherehavethepuzzlethatsofrequentlyoccursinthecaseofmusquitoes——onthebloodofwhatanimalsdotheseinsectscommonlyfeed?Theguanacoisnearlytheonlywarm-bloodedquadruped,anditisfoundinquiteinconsiderablenumberscomparedwiththemultitudeofflies。
ThegeologyofPatagoniaisinteresting。DifferentlyfromEurope,wherethetertiaryformationsappeartohaveaccumulatedinbays,herealonghundredsofmilesofcoastwehaveonegreatdeposit,includingmanytertiaryshells,allapparentlyextinct。Themostcommonshellisamassivegiganticoyster,sometimesevenafootindiameter。Thesebedsarecoveredbyothersofapeculiarsoftwhitestone,includingmuchgypsum,andresemblingchalk,butreallyofapumiceousnature。Itishighlyremarkable,frombeingcomposed,toatleastone-tenthofitsbulk,ofInfusoria。ProfessorEhrenberghasalreadyascertainedinitthirtyoceanicforms。Thisbedextendsfor500
milesalongthecoast,andprobablyforaconsiderablygreaterdistance。
AtPortSt。Julianitsthicknessismorethan800feet!Thesewhitebedsareeverywherecappedbyamassofgravel,formingprobablyoneofthelargestbedsofshingleintheworld:itcertainlyextendsfromneartheRioColoradotobetween600and700nauticalmilessouthward,atSantaCruzariveralittlesouthofSt。Julian,itreachestothefootoftheCordillera;halfwayuptheriver,itsthicknessismorethan200feet;
itprobablyeverywhereextendstothisgreatchain,whencethewell-roundedpebblesofporphyryhavebeenderived:wemayconsideritsaveragebreadthas200miles,anditsaveragethicknessasabout50feet。Ifthisgreatbedofpebbles,withoutincludingthemudnecessarilyderivedfromtheirattrition,waspiledintoamound,itwouldformagreatmountainchain!
Whenweconsiderthatallthesepebbles,countlessasthegrainsofsandinthedesert,havebeenderivedfromtheslowfallingofmassesofrockontheoldcoast-linesandbanksofrivers,andthatthesefragmentshavebeendashedintosmallerpieces,andthateachofthemhassincebeenslowlyrolled,rounded,andfartransportedthemindisstupefiedinthinkingoverthelong,absolutelynecessary,lapseofyears。Yetallthisgravelhasbeentransported,andprobablyrounded,subsequentlytothedepositionofthewhitebeds,andlongsubsequentlytotheunderlyingbedswiththetertiaryshells。
Everythinginthissoutherncontinenthasbeeneffectedonagrandscale:
theland,fromtheRioPlatatoTierradelFuego,adistanceof1200miles,hasbeenraisedinmassandinPatagoniatoaheightofbetween300and400feet,withintheperiodofthenowexistingsea-shells。Theoldandweatheredshellsleftonthesurfaceoftheupraisedplainstillpartiallyretaintheircolours。Theuprisingmovementhasbeeninterruptedbyatleasteightlongperiodsofrest,duringwhichtheseaate,deeplybackintotheland,formingatsuccessivelevelsthelonglinesofcliffs,orescarpments,whichseparatethedifferentplainsastheyriselikestepsonebehindtheother。Theelevatorymovement,andtheeating-backpoweroftheseaduringtheperiodsofrest,havebeenequableoverlonglinesofcoast;forIwasastonishedtofindthatthestep-likeplainsstandatnearlycorrespondingheightsatfardistantpoints。Thelowestplainis90feethigh;andthehighest,whichIascendednearthecoast,is950
feet;andofthis,onlyrelicsareleftintheformofflatgravel-cappedhills。TheupperplainofSantaCruzslopesuptoaheightof3000feetatthefootoftheCordillera。Ihavesaidthatwithintheperiodofexistingsea-shells,Patagoniahasbeenupraised300to400feet:Imayadd,thatwithintheperiodwhenicebergstransportedbouldersovertheupperplainofSantaCruz,theelevationhasbeenatleast1500feet。NorhasPatagoniabeenaffectedonlybyupwardmovements:theextincttertiaryshellsfromPortSt。JulianandSantaCruzcannothavelived,accordingtoProfessorE。Forbes,inagreaterdepthofwaterthanfrom40to250feet;buttheyarenowcoveredwithsea-depositedstratafrom800to1000feetinthickness:
hencethebedofthesea,onwhichtheseshellsoncelived,musthavesunkdownwardsseveralhundredfeet,toallowoftheaccumulationofthesuperincumbentstrata。Whatahistoryofgeologicalchangesdoesthesimply-constructedcoastofPatagoniareveal!
AtPortSt。Julian,[12]insomeredmudcappingthegravelonthe90-feetplain,IfoundhalftheskeletonoftheMacraucheniaPatachonica,aremarkablequadruped,fullaslargeasacamel。ItbelongstothesamedivisionofthePachydermatawiththerhinoceros,tapir,andpalaeotherium;butinthestructureofthebonesofitslongneckitshowsaclearrelationtothecamel,orrathertotheguanacoandllama。Fromrecentsea-shellsbeingfoundontwoofthehigherstep-formedplains,whichmusthavebeenmodelledandupraisedbeforethemudwasdepositedinwhichtheMacraucheniawasentombed,itiscertainthatthiscuriousquadrupedlivedlongaftertheseawasinhabitedbyitspresentshells。
Iwasatfirstmuchsurprisedhowalargequadrupedcouldsolatelyhavesubsisted,inlat。49degs。15’,onthesewretchedgravelplains,withtheirstuntedvegetation;buttherelationshipoftheMacraucheniatotheGuanaco,nowaninhabitantofthemoststerileparts,partlyexplainsthisdifficulty。
Therelationship,thoughdistant,betweentheMacraucheniaandtheGuanaco,betweentheToxodonandtheCapybara,——thecloserrelationshipbetweenthemanyextinctEdentataandthelivingsloths,ant-eaters,andarmadillos,nowsoeminentlycharacteristicofSouthAmericanzoology,——andthestillcloserrelationshipbetweenthefossilandlivingspeciesofCtenomysandHydrochaerus,aremostinterestingfacts。Thisrelationshipisshownwonderfully——aswonderfullyasbetweenthefossilandextinctMarsupialanimalsofAustralia——bythegreatcollectionlatelybroughttoEuropefromthecavesofBrazilbyMM。LundandClausen。Inthiscollectionthereareextinctspeciesofallthethirty-twogenera,exceptingfour,oftheterrestrialquadrupedsnowinhabitingtheprovincesinwhichthecavesoccur;andtheextinctspeciesaremuchmorenumerousthanthosenowliving:therearefossilant-eaters,armadillos,tapirs,peccaries,guanacos,opossums,andnumerousSouthAmericangnawersandmonkeys,andotheranimals。Thiswonderfulrelationshipinthesamecontinentbetweenthedeadandtheliving,will,Idonotdoubt,hereafterthrowmorelightontheappearanceoforganicbeingsonourearth,andtheirdisappearancefromit,thananyotherclassoffacts。