ThesetwospeciesofAmblyrhynchusagree，asIhavealreadystated，intheirgeneralstructure，andinmanyoftheirhabits。Neitherhavethatrapidmovement，socharacteristicofthegeneraLacertaandIguana。Theyarebothherbivorous，althoughthekindofvegetationonwhichtheyfeedissoverydifferent。Mr。Bellhasgiventhenametothegenusfromtheshortnessofthesnout：indeed，theformofthemouthmayalmostbecomparedtothatofthetortoise：oneisledtosupposethatthisisanadaptationtotheirherbivorousappetites。Itisveryinterestingthustofindawell-characterizedgenus，havingitsmarineandterrestrialspecies，belongingtosoconfinedaportionoftheworld。Theaquaticspeciesisbyfarthemostremarkable，becauseitistheonlyexistinglizardwhichlivesonmarinevegetableproductions。AsIatfirstobserved，theseislandsarenotsoremarkableforthenumberofthespeciesofreptiles，asforthatoftheindividuals，whenwerememberthewell-beatenpathsmadebythethousandsofhugetortoises——themanyturtles——thegreatwarrensoftheterrestrialAmblyrhynchus——andthegroupsofthemarinespeciesbaskingonthecoast-rocksofeveryisland——wemustadmitthatthereisnootherquarteroftheworldwherethisOrderreplacestheherbivorousmammaliainsoextraordinaryamanner。ThegeologistonhearingthiswillprobablyreferbackinhismindtotheSecondaryepochs，whenlizards，someherbivorous，somecarnivorous，andofdimensionscomparableonlywithourexistingwhales，swarmedonthelandandinthesea。Itis，therefore，worthyofhisobservation，thatthisarchipelago，insteadofpossessingahumidclimateandrankvegetation，cannotbeconsideredotherwisethanextremelyarid，and，foranequatorialregion，remarkablytemperate。
Tofinishwiththezoology：thefifteenkindsofsea-fishwhichIprocuredhereareallnewspecies；theybelongtotwelvegenera，allwidelydistributed，withtheexceptionofPrionotus，ofwhichthefourpreviouslyknownspeciesliveontheeasternsideofAmerica。Ofland-shellsIcollectedsixteenkindsandtwomarkedvarieties，ofwhich，withtheexceptionofoneHelixfoundatTahiti，allarepeculiartothisarchipelago：asinglefresh-watershellPaludinaiscommontoTahitiandVanDiemen’sLand。Mr。Cuming，beforeourvoyageprocuredhereninetyspeciesofsea-shells，andthisdoesnotincludeseveralspeciesnotyetspecificallyexamined，ofTrochus，Turbo，Monodonta，andNassa。Hehasbeenkindenoughtogivemethefollowinginterestingresults：Oftheninetyshells，nolessthanforty-sevenareunknownelsewhere——awonderfulfact，consideringhowwidelydistributedsea-shellsgenerallyare。Oftheforty-threeshellsfoundinotherpartsoftheworld，twenty-fiveinhabitthewesterncoastofAmerica，andoftheseeightaredistinguishableasvarieties；theremainingeighteenincludingonevarietywerefoundbyMr。CumingintheLowArchipelago，andsomeofthemalsoatthePhilippines。ThisfactofshellsfromislandsinthecentralpartsofthePacificoccurringhere，deservesnotice，fornotonesinglesea-shellisknowntobecommontotheislandsofthatoceanandtothewestcoastofAmerica。Thespaceofopensearunningnorthandsouthoffthewestcoast，separatestwoquitedistinctconchologicalprovinces；
butattheGalapagosArchipelagowehaveahalting-place，wheremanynewformshavebeencreated，andwhitherthesetwogreatconchologicalprovinceshaveeachsentupseveralcolonists。TheAmericanprovincehasalsosenthererepresentativespecies；forthereisaGalapageianspeciesofMonoceros，agenusonlyfoundonthewestcoastofAmerica；andthereareGalapageianspeciesofFissurellaandCancellaria，generacommononthewestcoast，butnotfoundasIaminformedbyMr。CuminginthecentralislandsofthePacific。Ontheotherhand，thereareGalapageianspeciesofOnisciaandStylifer，generacommontotheWestIndiesandtotheChineseandIndianseas，butnotfoundeitheronthewestcoastofAmericaorinthecentralPacific。Imayhereadd，thatafterthecomparisonbyMessrs。CumingandHindsofabout2000shellsfromtheeasternandwesterncoastsofAmerica，onlyonesingleshellwasfoundincommon，namely，thePurpurapatula，whichinhabitstheWestIndies，thecoastofPanama，andtheGalapagos。
Wehave，therefore，inthisquarteroftheworld，threegreatconchologicalsea-provinces，quitedistinct，thoughsurprisinglyneareachother，beingseparatedbylongnorthandsouthspaceseitheroflandorofopensea。
Itookgreatpainsincollectingtheinsects，butexceptingTierradelFuego，Ineversawinthisrespectsopooracountry。EvenintheupperanddampregionIprocuredveryfew，exceptingsomeminuteDipteraandHymenoptera，mostlyofcommonmundaneforms。Asbeforeremarked，theinsects，foratropicalregion，areofverysmallsizeanddullcolours。OfbeetlesIcollectedtwenty-fivespeciesexcludingaDermestesandCorynetesimported，whereverashiptouches；ofthese，twobelongtotheHarpalidae，twototheHydrophilidae，ninetothreefamiliesoftheHeteromera，andtheremainingtwelvetoasmanydifferentfamilies。ThiscircumstanceofinsectsandImayaddplants，wherefewinnumber，belongingtomanydifferentfamilies，is，Ibelieve，verygeneral。Mr。Waterhouse，whohaspublished[4]anaccountoftheinsectsofthisarchipelago，andtowhomIamindebtedfortheabovedetails，informsmethatthereareseveralnewgenera：andthatofthegeneranotnew，oneortwoareAmerican，andtherestofmundanedistribution。Withtheexceptionofawood-feedingApate，andofoneorprobablytwowater-beetlesfromtheAmericancontinent，allthespeciesappeartobenew。