336 



MAMMALIA. 



Atelodus) had a very wide distribution in the Pliocene and Pleistocene 

 periods, though they are now exclusively confined to Africa (R. bicornis 

 and R. simus). They seem to appear first in the Lower Pliocene of 

 Pikermi, Greece (R. pachygnathus), and become common over the greater 

 part of southern Europe in the Upper Pliocene (R. etruscus) the latter 

 ranging as far north as the Forest Bed of Cromer, Norfolk. The Upper 

 Pliocene species bore horns so large that the septum between the nares 

 began to ossify for their support; and the same ossification is to be 

 noticed in the slender-nosed R. leptorhinus or hemitoechus (fig. 193) from 

 the early Pleistocene of the Thames Valley and parts of the adjoining 



FIG. 133. 



Rhinoceros leptorhinus ; skull and mandible, one-eighth nat. size. Pleistocene ; 

 Ilford, Essex. (After W. Davies.) 



continent. The ossification of the nasal septum, however, attained its 

 maximum development in the great Woolly or Tichorhine Rhinoceros 

 (R. antiqiiitatis), which is found in the English caves and river-deposits, 

 in the old river-deposits at the bottom of the present North Sea, and 

 ranged throughout northern Europe and Asia, wandering even within 

 the Arctic Circle. Mummified remains discovered in the frozen earth of 

 northern Siberia prove this animal to have been thickly clothed with hair 

 arid wool ; and its huge horns are preserved in the same deposits. 



Elasmotherium. This is an aberrant rhinoceros, which ranged over 

 Siberia and part of south European Russia in the Pleistocene period. 

 The nasal bones are slender, but the nasal septum is ossified, and there is 

 an enormous bony prominence on the frontal region above the eye, which 

 must have borne a relatively large horn. The nasal region may perhaps 



