Peterson: Material Discovered in Uinta Basin. 67 



cross-crest. Absence of hypocone on M-. Presence or absence of 

 "hypocone" on M- and M-. A feebly developed paraconid on Mj 

 {in Homacodon only). A strong tendency towards the quadricuspid 

 selenodon! structure of the molar dentition. 



Genus Bunomeryx Wortman. 

 14. Bunomeryx elegans Wortman (Plate XXXVII, Fig. 18). 



Bull. Amer. Mus. Nat. Hist. Vol. X, 1898, p. 97. 



Three specimens, C. M. Nos. 2951, 2949, and 3063, are referred to 

 this species. The specimens are represented by lower jaws; they are 

 smaller than the type specimen of B. montanus (see PI. XXXVI, 

 Figs. 3-4) and in this respect more nearly agree with B. elegans 

 Wortman. There is, however, a shorter diastema between P2- and P-g 

 than in the latter species, and the accessory cusps of P3- are better 

 developed. The tooth regarded as the canine by Wortman is of a 

 trenchant character, with the apex a little recurved and elevated 

 slightly above the crown of the succeeding tooth. The tooth has the 

 appearance of a sub-caniniform premolar, in which event Bunomeryx 

 would have four instead of three lower premolars. The tooth in 

 front of this so-called canine is equally large and its crown also of the 

 same detailed structure. It would therefore appear that Py in Buno- 

 meryx was mistaken for a canine, while there are only two incisors. 

 The latter are suddenly reduced in size and have typical fan-shaped 

 crowns. 



Genus Hylomeryx gen. nov. 



Type: Anterior portion of skull and lower jaws, C. M. No. 2335. 



Paratype: Fragments of upper teeth, portion of cast of brain, and 

 both mandibular rami, C. M. No. 2944. 



Horizon: Near the base of Horizon C, Uinta Eocene. 



Locality: Eastern border of Uinta Basin, near Vernal on the Uinta 

 Railroad Stage-road, Uinta Basin, Utah. 



Generic Characters: I ^' Cy- Pf* ilff. Homacodon-like dentition, but 

 with short diastema between P- and P-. Premolars heavier and of 

 relatively greater antero-posterior diameter than in Homacodon. Cin- 

 guliim of the premolars rather slightly, or not at all, indicated. Absence 

 of antero- and poster o-external cuspules on P- as in Bunomeryx. Pro- 

 tocone and protocunule united into a cross-crest on M- and M-. Pj with 

 distinct internal tubercle; Py with deuteroconid; antero-internal tuj^ercle 



