338 ILLOGICAL GEOLOGY. 



for in those of contemporaneous strata ; and the recent 

 forms exhumed in any one of these regions would very un- 

 truly represent the present Flora and Fauna of the Earth. 

 In conformity with the current style of geological reason- 

 ing, an exhaustive examination of deposits in the Arctic cir- 

 cle, might be held to prove that though at this period 

 there were sundry mammals existing, there were no reptiles ; 

 while the absence of mammals in the deposits of the Gala- 

 pagos Archipelago, where there are plenty of reptiles, might 

 be held to prove the reverse. And at the same time, from 

 the formations extending for two thousand miles along the 

 great barrier-reef of Australia — formations in which are 

 imbedded nothing but corals, echinoderms, mollusks, crus- 

 taceans, and fish, along with an occasional turtle, or bird, 

 or cetacean, it might be inferred that there lived in our 

 epoch neither terrestrial reptiles nor terrestrial mammals. 



The mention of Australia, indeed, suggests an illustra- 

 tion which, even alone, would amply prove our case. The 

 Fauna of this region differs widely from any that is found 

 elsewhere. On land all the indigenous mammals, except 

 bats, belong to the lowest, or implacental division ; and the 

 insects are singularly different from those found elsewhere. 

 The surrounding seas contain numerous forms that are more 

 or less strange ; and among the fish there exists a species 

 of shark, which is the only hving representative of a genus 

 that flourished in early geologic epochs. If, now, the mod- 

 ern fossiliferous deposits of Australia were to be examined 

 by one ignorant of the existing Australian Fauna ; and if he 

 were to reason in the usual manner ; he would be very un- 

 likely to class these deposits with those of the present time. 

 How, then, can we place confidence in the tacit assumption 

 that certain formations in remote parts of the Earth are 

 referable to the same period, because the organic remains 

 contained in them display a certain community of charac- 

 ter ? or that certain others are referable to different periods, 

 because the fades of their Faunas are different ? 



