288 Bulletin American Museum of Natural History. [Vol. XVI, 



Length of superior molar series, including canine. . . 134 mm. 



Anteroposterior diameter of canine at base 24 



Length of true molar series 46 



Transverse diameter of first superior molar 27 



Anteroposterior diameter of superior sectorial 27 



Width of palate at first molar, including crowns ... 98 



Amphicyon sinapius, n. sp. 



? Cants, sp. incerta, Cope, Rep. Vert. Pal. Col. U. S. G. S. Terrs. 

 Ann. Rep. 1873 (1874), 519. 



A larger American species of Amphicyon is represented by 

 a number of fragmentary specimens from the Colorado Loup 

 Fork. 



Am. Mus. No. 9358. 



9357- 

 ?9356. 

 ?93S5- 



?8248. 



Jaw fragment with broken carnassial and com- 

 plete first tubercular molar. Type. 



Carnassial tooth, unworn. Co-type. 



Twenty- three vertebras, ribs, humerus, and ulna. 



Astragalus, parts of tibia, humerus, radius, and 

 several metapodials, of uncertain association. 



(Cope Coll.) . Astragalus, and anterior part of a 

 lower jaw, without teeth. 



Our material unfortunately does not enable us to determine 

 the dental formula, but the characters of the teeth agree best 

 "•^ with those of Amphi- 



cyon, and are more pri- 

 mitive than those of 

 Dinocyon. It is much 

 larger than A. lemanen- 

 sis, but resembles rather 

 nearly the figures of that 

 genus given by Dr. 

 Schlosser. It somewhat 

 exceeds A . major and A . 

 giganteus in size, the heel 

 of nij is broader, m^ is 

 much larger and broader 

 comparing it with de 

 molars the entoconid is 

 represented only by a broad cingular ridge. Both in size 



Fig. 2. AtnphKyon sinaptus. Part of lower 

 jaw, inner side, x §. Type, No. 9358. Loup Fork 

 (Pawnee Creek Beds), Colorado. 



Blainville's figures, and on both 



