iQoo.] Osborn, Phylogeny of the Rhinoceroses of Europe. 247 



in length to 75), Paris, Coll. Lartet, Nos. 2518, 2537; long, stilted digits; 

 metacarpal III enlarged ; metacarpals II, IV relatively smaller. Scapula ver- 

 tically elongate, with long neck, as in all long-limbed, speedy types. 



Dental distinctions. — Inferior canines less lance-shaped, with internal flare 

 and flattened external section. First lower premolar sometimes present (in the 

 slightly older Sansan specimens). Sup. premolars and molars (No. 2379) with 

 somewhat reduced antecrochet and very strong crochet placed near ectoloph ; 

 this unites with the ectoloph when well worn and forms a conspicuous medi- 

 fossette (No. 2388). Crista conspicuous in unworn premolars and molars. An- 

 tecrochet somewhat reduced and becoming conspicuous only in old or worn 

 teeth. Molars with cingulum entering median valley between crests, a crest in 

 the bottom of median valley (No. 2388), or embracing protoloph only ; with 

 postfossette in m^ ; and traces of external cingulum ; posterior cingulum of m* 

 (also observed in A. platycephalum and A. lemanense) persisting. Measure- 

 ments, female, pm- — m^ = 230. 



The scapulae and limb bones of large size in the Paris Museum 

 (which are catalogued R. sansaniensis) undoubtedly belong to 

 A. tetradactyliiDi. Some of these indicate an Aceratherine race 

 as large as or larger than the A. lemanense type. 



Paris : This species is also represented in the slightly higher 

 levels of Simorre, especially by a very large jaw of z. female, with 

 small lower canines, first lower premolar absent, formula : pg — 

 nig ; of marked dolichocephalic type. London : The jaw from 

 Sansan (Hastings Collection, No. 27454, catalogued R.goldfussi) 

 also represents this species ; it is large and dolichocephalic in 

 type ; the lower canines are flattened with a marked internal flare. 



5. Upper Miocene Stage. 



Georgensgemiind. 



Munich : Upper teeth with closely similar characters (cata- 

 logued A. incisiviim, Georg- 

 ensgemiind, Bav.) are seen 

 here in a shade earlier stage 

 of evolution, because we 

 observe more of a bridge 

 between the premolar crests 

 and somewhat greater 

 prominence of the antecro- 

 chet as well as of the internal 

 cingulum of the molars. pAnother specimen is a characteristic 



Fis 



g«. 



3378. X 



A ceratheriuin tetradactyluiii. 

 Paris. 



No. 



