118 THE GENEALOGY OF ANIMALS iv 



rarely goes further back than the " Ante-period," 

 which precedes that in which the remains of 

 animals belonging to that group are found. Thus, 

 as fossil remains of the majority of the groups of 

 Eeptilia are first found in the Trias, they are 

 assumed to have originated in the "Antetriassic " 

 period, or between the Permian and Triassic 

 epochs. 



I confess this is wholly incredible to me. The 

 Permian and the Triassic deposits pass completely 

 into one another ; there is no sort of discontinuity 

 answering to an unrecorded " Antetrias " ; and, 

 what is more, we have evidence of immensely 

 extensive dry land during the formation of these 

 deposits. We know that the dry land of the Trias 

 absolutely teemed with reptiles of all groups 

 except Pterodactyles, Snakes, and perhaps Tor- 

 toises ; there is every probability that true Birds 

 existed, and Mammalia certainly did. Of the in- 

 habitants of the Permian dry land, on the contrary, 

 all that have left a record are a few lizards. Is it 

 conceivable that these last should really represent 

 the whole terrestrial population of that time, and 

 that the development of Mammals, of Birds, and 

 of the highest forms of Reptiles, should have been 

 crowded into the time during which the Permian 

 conditions quietly passed away, and the Triassic 

 conditions began ? Does not any such supposition 

 become in the highest degree improbable, when, 

 in the terrestrial or fresh- water Labyrinthodonts, 



