37o 



CLASS MAMMALIA. 



a more complex type ; there being an absence of a buttress at the 

 antero-external angle, and the folds of the crown so arranged that 

 when more worn than in the figured specimen three islands of 

 enamel would be formed on their crowns. These teeth are also 

 characterised by their plane of wear being perfectly horizontal, and 

 by their relatively tall crowns. An early member of this type is R. 

 platyrhinus, of the Pliocene of Northern India ; from which species 



Fig. 1245. 



-The second right upper true molar of Rhinoceros antiqiritatis ', from the 

 Pleistocene of Kent. 



it is highly probable that both the existing African R. simus, and 

 the Pleistocene R. antiquttatis, of Northern Asia and Europe, have 

 been derived. 



The latter species, of which the skull is represented in fig. 1246 and an 

 upper molar in fig. 1245, is sometimes known as the Woolly Rhinoceros, 

 since it was covered with a thick coat of woolly hair. The skin was 

 devoid of the folds which characterise the large Indian species ; and the 

 front horn was of very large size. As in some of the Pleistocene species 

 the septum of the nares was completely ossified (fig. 1246). This species 

 is essentially a northern form, and has nearly the same distribution 

 as the Mammoth, although it does not appear to have crossed Behring 

 Strait into America. In time this Rhinoceros makes its first appearance 

 in the Pleistocene Brick-earths of the Thames valley, and is very common 

 in European cave-deposits, and in the tundras of Siberia. Complete 

 carcasses, still covered with the dried flesh, skin, and hair, have not unfre- 

 quently been found washed out from the frozen alluvial deposits of these 

 tundras on the banks of the Yenesi and Lena ; from which we learn that 



