156 OEIGIN OF LIFE IN AMEEICA 



cene deposits. On the other hand, we have noted that pec- 

 caries lived in the United States during the Pleistocene and 

 the preceding .geological periods. They were not exterminated 

 by the severity of the climate. Representatives of the peccary 

 family not only survived the Glacial Epoch, they even showed 

 their indifference to it by invading the area which had only 

 just been forsaken by the supposed Wisconsin glacier, for 

 their remains, as Dr. Hay tells us, were found in deposits 

 overlying the Wisconsin drift at three different localities. 

 In the single cave in which the reindeer occurred its re- 

 mains were mingled with those of a species of peccary, 

 (Tayassus tetragonus) very closely allied to that still living 

 in the Southern States and in South America. Nor was the 

 Glacial Epoch any more trying to the great ground sloth,, 

 Megalonyx, for it also survived it and invaded the area covered 

 by the drift. The remains of a species of that giant edentate 

 were found some years ago, according to Dr. Hay, in an old 

 filled -up pond, just within the alleged outermost moraine of 

 the Wisconsin glacier near Millexsburg in Ohio. My Own 

 views as to the nature of the climate prevailing during the 

 Pleistocene Period, and particularly during that phase of it 

 known as the " Glacial Epoch " or Ice Age, are derived from 

 a careful scrutiny of the living and extinct fauna and flora. 

 This study of the animals and plants does not reveal to me' 

 that the Pleistocene Period was a period of extreme cold. 

 On the contrary, as I remarked before, the climate seems to 

 have been milder in a large portion of the northern 

 hemisphere than it is at present. An apparent increase of 

 temperature after the passing away of the " Ice Age " is 

 supposed to be indicated by the appearance of forms of animal 

 and plant life requiring a higher temperature than is com- 

 patible with the arctic condition believed to have prevailed 

 during the height of the Glacial Epoch. It is really due, I 

 think, to that perfectly natural re-occupation of tracts of 

 country on which both plants and animals had been destroyed. 

 The destructive agent, in my opinion, was not ice but water. 

 Glaciers no doubt existed on all the higher mountains near 

 the Atlantic and Pacific coasts. They owed their presence, 

 however, not to cold, but principally, as I mentioned before, 

 to the higher temperature of the eastern and western oceans. 



