314 THE TRANSFORMATIONS OF THE ANIMAL WORLD 



(Blastomeryx, akin to the Dicrocerus), and the 

 Mastodons with tapir-like teeth. Finally, a last 

 invasion shows itself at the Pliocene epoch in the 

 strata of Loup-Fork, in which are discovered the 

 Mustelce, the Otters and the Pseudoluri. Given the 

 small probability of direct connection between 

 Europe and America in Neogene times, this rather 

 favours the idea that the two last migrations 

 may have arrived in North America by way of the 

 Asiatic countries and the Behring Straits. 



However this may be, the great retreat of the sea 

 which characterizes the first half of the Quaternary 

 brought ajbout the emergence of a great Arctic con- 

 tinent which favoured the dispersion over the whole 

 region of the North of Asia, Europe, and America, 

 of a fauna which comprises the Elk, the Reindeer, 

 the Musk-ox, the Mammoth, the Marmot, the Field- 

 mice, the Lemmings, the Shrew-mice, the Bears, 

 and the great Quaternary Felines. 



I shall be more concise as regards the other conti- 

 nents of the earth. The fragments of the great 

 Austral continent : South America, Africa, Mada- 

 gascar, the Indian Peninsula, and Australia, must 

 likewise have been connected at certain periods 

 of the Tertiary era. I have already pointed out 

 above the migration towards Australia at a recent 

 epoch, difficult to define, of the group of Flesh-eating 

 Marsupials coming probably from South America 

 by way of the Antarctic continent. The com- 

 munications between South America and Africa 

 seem likewise established by the migration of the 

 Hyracoidse, the Hystricomorphous Rodents and, 

 perhaps, the Edentata with normal Vertebrae, 



