1898.] Osborn^ Skeleton of Coryphodons radians. ^1 



has a very short tuber-calcis and bore the pes slightly more planti- 

 grade than the Elephant. Coryphodon has a tuber-calcis inter- 

 mediate in length ; in the astragalus the upper facet for the tibia 

 and lower facet for the navicular presents an oblique angle, the 

 astragalus thinning out to a sharp edge in front (whereas in Uinta- 

 theriuin these facets are more nearly parallel, and the astragalus 

 is truncate in front). The angles between the tibial and navicu- 

 lar facets of the astragalus, as shown in sections in Fig. 2, 

 afford the most decisive evidence that the pes of Coryphodon was 

 intermediate between the nearly plantigrade Pantolambda and the 

 sub-digitigrade Uintatherium. 



Coryphodon had a very short back and short, spreading limbs, 

 with a very clumsy, shuffling gait. 



The rudimentary horn observed for the first time in the parie- 

 tals is prophetic of the great parietal horn of Uintatherium. 

 Many other characters of the skull and skeleton are also prophetic, 

 but there is little tendency displayed to reduce the upper incisors 

 or lower canines into the Uintathere type. 



' The Perissodactyl affinities of the animal were dwelt upon in Professor Marsh's earlier 

 papers (Am. Jour. Sc, 1876, page 428; op. cit., j&t;, page 84), but were abandoned subse- 

 quently (' Dinocerata,' 1884, page 177), in which Coryphodon w^ls correctly associated with 

 Uintatherium in the Amblydactyla (Amblypoda). 



