The Rise of the Mammals 



well as several species of rhinoceroses. Some 

 of these were heavily built and apparently 

 aquatic in habit, while others were of lighter 

 build and evidently made for running. Most 

 of these early rhinoceroses departed widely 

 from our ideas of these animals, for they were 

 quite hornless. 



During the Miocene period rhinoceroses 

 were still abundant in North America, and if 

 some of them had no horns (Aceratheriurn), 

 others made up for this by having two (Dicera- 

 therium), one on either side of the nose, some- 

 thing like the bygone titanotheres. The most 

 peculiar member of the group was one of the 

 hornless species named Aphelopsfossiger, having 

 the short legs of a hippopotamus, and probably 

 aquatic in its habits. In some parts of the 

 West these short-legged rhinoceroses abounded, 

 and the Miocene sands of Kansas have yielded 

 the bones of thousands. These have been found 

 in such close association that it has been sug- 

 gested they perished from the effects of an 

 unusually severe season, which drove them 

 together in search of some last spot where 



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