Ifweallow, withPictet, thatDarwinstheorywillverywellserveforallthatconcernsthepresentepochoftheworldshistory—anepochinwhichthisrenownedpaleontologistincludesthediluvialorquaternaryperiod—thenDarwinsfirstandforemostneedinhisonwardcourseisapracticableroadfromthisintoandthroughthetertiaryperiod, , byshowingthatinthephysicalgeologythereisnogeneralorabsolutebreakbetweenthetwo, , theLyellianviewis, wesuppose, , , accordingtoDesHayes, Lye!!, and, ifwemistakenot, Bronn, , however, , initsbearingsonthenewtheory, , withAgassiz, doubtthespecificidentityinanyofthesecases, andthosewhosay, withPictet, that "thelatertertiarydepositscontainingeneralthedebrisofspeciesverynearlyrelatedtothosewhichstillexist, belongingtothesamegenera,butspecificallydifferent," mayalsoagreewithPictet,thatthenearly-relatedspeciesofsuccessivefaunasmustormayhavehad "amaterialconnection." —isdemonstrablythenaturaloneasrespectsallthosetertiaryspecieswhichexperiencednaturalistshavepronouncedtobeidenticalwithexistingones, butwhichothersnowdeemdistinctFortoidentifythetwoisthesamethingastoconcludetheonetobetheancestoroftheotherNodoubttherearedifferencesbetweenthetertiaryandthepresentindividuals, differencesequallynoticedbybothclassesofnaturalists, butdifferentlyestimatedBytheonethesearedeemedquitecompatible, bytheotherincompatible, withcommunityoforiginButwhocantelluswhatamountofdifferenceiscompatiblewithcommunityoforigin? Thisistheveryquestionatissue, andonetobesettledbyobservationaloneWhowouldhavethoughtthatthepeachandthenectarinecamefromonestock? But, thisbeingprovedisitnowveryimprobablethatbothwerederivedfromthealmond, orfromsomecommonamygdalineprogenitor?Whowouldhavethoughtthatthecabbage, cauliflower,broccolikale, andkohlrabiarederivativesofonespecies, andrapeorcolza, turnip, andprobablyrutabaga, ofanotherspecies? Andwhothatisconvincedofthiscanlongundoubtinglyholdtheoriginaldistinctnessofturnipsfromcabbagesasanarticleoffaith? Onscientificgroundsmaynotaprimordialcabbageorrapebeassumedastheancestorofallthecabbageraces, onmuchthesamegroundthatweassumeacommonancestryforthediversifiedhumanraces? IfallOurbreedsofcattlecamefromonestockwhynotthisstockfromtheauroch, whichhashadallthetimebetweenthediluvialandthehistoricperiodsinwhichtosetoffavariationperhapsnogreaterthanthedifferencebetweensomesortsofdomesticcattle?ThatconsiderabledifferencesareoftendiscerniblebetweentertiaryindividualsandtheirsupposeddescendantsofthepresentdayaffordsnoargumentagainstDarwinstheory, ashasbeenrashlythought,, thenDarwinsopponents,whoarguetheimmutabilityofspeciesfromtheibisesandcatspreservedbytheancientEgyptiansbeingjustlikethoseofthepresentday, couldtriumphantlyaddafewhundredthousandyearsmoretothelengthoftheexperimentandtotheforceoftheirargument.
