SUBORDER C 



PERISSODACTYLA 



143 



later, but continued on into postglacial time. It seems to he allied to 

 B. platyrhinus. 



Subfamily 4. Elasmotheriinae Gill. 



Skull elongated, with tapering pointed snout and much elevated, rugose, hemi- 

 spherical protuberance on the frontal hone. Nasal hones slender, with a small rough 



0.0.2 3 



surface on the most anterior portion only. Dental formula : ' ' -^~- Cheek teeth 



prismatic, rootless; superior molars composed of ectoloph and two oblique transverse 



Elasmotherium sibiricubvi Fischer. Pleistocene, Siberia. J, Skull, lateral aspect, i/iq. 

 B, C, Upper and lower molars, crown view. 1/4- (After Brandt.) 



crests ; inferior molars with two crescents ; enamel elaborately crimped. Premolars 

 above and below smaller and somewhat simpler than molars. Skeleton robust. 

 Mamis and pes tridactyl. 



Elasmotherium Fischer (Fig. 189). E. sibiricum, the only species, is found 

 in the older Pleistocene of southern Russia and Siberia ; very rarely, 

 also, in Germany. 



Sinotherium Ringstrom. Ancestral to former genus. Pliocene, Shansi, 

 China. 



Subfamily 5. Baluchitheriina Osborn.^ 



Head relatively small and neck much elongated, the cervical vertebrae being of 

 very light construction. Skull much elongated, and nasal bones slender without horn. 



Dental formula : ' ' ; upper incisor caniniform ; lower incisor procumbent. 



Feet much elongated, tridactyl. the middle metapodial longest and stoutest. 



Gigantic long-limbed and long-necked rhinoceroses, found in Oligocene or 

 Miocene formations in Asia. Probably including the largest known land 

 mammals. 



^ Borissmk, A., Tndricothermm, n.g. Mem. Acad. Sci. Riissie [8], vol. xxxv., no. 6, 1923. — 

 Cooper, O. Forster, Baluchitherium osborrii. Phil. Trans. Roy. Soc. Lond., ser. B, no. 392, 1923. 

 On the Skull and Dentition of Paraceratherium hugtiense. Ibid., no. 399, 1924. — Osborn, H. F,, 

 Baluchitlieriuni grangeri. Amer. Mus. Novitates, no. 78, 1923. Also Natural History, New York, 

 vol. xxiii., no. 3, 1923. 



