SOME EARLY MAMMALS 235 



work of the modern ruminant type ; l thus it resembled the ox 

 in having an equally divided hoof, or rather two hoofs. Fig. 87, 

 in which the skeleton is seen, shows that it possessed a long tail. 

 In size it was about equal to a fallow deer, and the long tail 

 has been supposed, perhaps erroneously, to indicate aquatic 

 habits. Small and more delicate species have been taken to 

 represent distinct genera. 



"Judging from its habits of swimming and diving," said 



FIG. 87. Skeleton with restored outline of Anoplotherium commune, from 

 Eocene strata. (After Cuvier.) 



Cuvier, "the Anoplotherium would have the hair smooth like 

 the otter; perhaps its skin was even half naked. It is not 

 likely, either, that it had long ears, which would be incon- 

 venient in its aquatic kind of life ; and 1 am inclined to think 

 that, in this respect, it resembled the hippopotamus and other 



1 Cuvier divided all the hoofed animals (ungulates) into two orders, 

 pachyderms and ruminants. The former is a heterogeneous order, and has 

 since been abandoned ; but the ruminants have been regarded as one of the 

 most distinct of mammalian orders, for they are separated from all other 

 animals by having horns and hoofs in pairs, the absence of upper front teeth, 

 complex stomachs, and the habit of ruminating or " chewing the cud." 

 Professor Owen showed that ungulates should be classified by the structure of 

 their feet. He therefore divided them into odd-toed (perissodactylate) and 

 even-toed (artiodactylate), and he placed elephants in a separate order the 

 Proboscidia. 



