262 Bulletin Atnerican Museum of Natural History. [Vol. XIII, 



England, with a nasal septum ; R. platyrhinus of the Pliocene 

 Siwaliks of India (which Lydekker has mistakenly associated with 

 the Atelodinae); finally, the smaller and somewhat primitive 

 living species, R. sumatrensis. 



Subfamily ATELODINyE. PHYLUM V. 



Lower Pliocene to recent Rhinoceroses. Dolichocephalic , long loiv skulls, 

 vioderately broad, depressed, backwardly inclined occiput ; two large horns 

 developed upon nasals and frontals ; nasals square or blunted anteriorly, 

 horns extending to the extremities ; Atelodine, cutting teeth vestigial or 

 wanting ; mesopodal, moderately long limbs and digits, similar to those of R, 

 indicus. 



I. Lower Pliocene Stage. 

 Piker mi ^ Maragha. 



In the Lower Pliocene of Pikermi there suddenly appears in 

 Europe a fifth type which cannot be derived from any of the 

 preceding ; the cutting teeth are precociously vestigial or wanting 

 (hence the term Atelodinae) ; the skull is easily distinguished by 

 the form of the temporal fossa and occiput, by the form of the 

 nasals and by the absence of front teeth in the dolichocephalic 

 megalodine R. schleiermacheri, which appears in the same beds. 

 The species is not found in the more northern Eppelsheim beds, 

 and in view of the many resemblances which the Pikermi type, 

 R. pachyg?uzthus, bears to the existing African species {R. simus, 

 R. dicornis), we may not consider as unreasonable the hypothesis 

 that this is an African phylum which entered southern Europe 

 with the numerous Antelopes and Giraffes of Pikermi ; the later 

 members of this phylum are the Pleistocene R. hemitxchus and 

 R. ajitiquitatis (= tichorhi>ius), a.\\6. the recent R. sii?ius and ^. 

 bicornis. The main characters of this phylum are given above. 



R. pachygnathus Wagjier. — Paris : A fine skull and skeleton 

 of this type have been described and figured by Gaudry. Even in 

 the young skull there is a decided thickening for a frontal horn ; 

 the nasals are very broad and thick at the extremities ; the lower 

 jaw is without distinct angle, and a single convex sweep from 

 condyle to angle is very characteristic ; correlated with this we 

 observe a weak zygomatic arch and early reduced front teeth ; 

 the most distinctive feature is the backward sweep of the tem- 

 poral fossa, the low, backwardly inclined occiput. The molars are 

 brachyodont . In the older jaw the formula is : ioCo-p^m^. 



