NO. 8 UPPER EOCENE ARTIODACTYLA — GAZIN 9I 



the type of P. kayi is nowhere preserved; hence the profile given in 

 Peterson's illustration may be misleading. 



Poabromylus appears to be a valid genus most nearly resembling 

 Leptoreodon but with premolars somewhat distinctive and both pre- 

 molars and molars a little more hypsodont. 



POABROMYLUS KAYI si Peterson, 1931 



Type. — Left ramus of mandible with P3 to M3, inclusive, CM. 

 No. 11753. 



Horizon and locality. — Lapoint member of Duchesne River forma- 

 tion, near Teleodus quarry, 11 miles west of Vernal, Uinta County, 

 Utah. 



Discussion. — The specific characters of Poabromylus kayi are not 

 distinguished from those on a generic level, except that in size it is 

 much larger than other known leptotragulids. So far this is the only 

 Duchesnean artiodactyl which may be allocated to the Leptomerycidae. 



MEASUREMENTS IN MILLIMETERS OF DENTITION IN TYPE SPECIMEN OF 



Poabromylus kayi, cm. no. i 1753 



Length of lower cheek tooth series, P3-M3, inclusive 51.9 



Lower molar series, M1-M3, inclusive 35.5 



P3, anteroposterior diameter : greatest transverse diameter 8.8 : 4.0 



P4, anteroposterior diameter : greatest transverse diameter 8.8 : 5.1 



Ml, anteroposterior diameter : transverse diameter of talonid 8.9 : 6.70 



Ma, anteroposterior diameter 10.7 



M3, anteroposterior diameter : transverse diameter of trigonid 16.5 : 8.8 



a, Approximate. 



REFERENCES 

 Colbert, Edwin H. 



1938. Brachyhyops, a new bunodont artiodactyl from Beaver Divide, Wyo- 

 ming. Ann. Carnegie Mus., vol. 27, pp. 87-108, figs. 1-5. 



1941. The osteology and relationships of Ar chae ornery x, an ancestral rumi- 

 nant. Amer. Mus. Novitates, No. 1135, pp. 1-24, figs. 1-6. 

 Cope, Edward D. 



1873. Fourth notice of extinct Vertebrata from the Bridger and Green River 

 Tertiaries. Palaeont. Bull. No. 17, PP- i-4 (2, 3). 



1874a. Report on the vertebrate paleontology of Colorado. Ann. Rep. Geol. 

 and Geogr. Surv. Terr, for 1873 (Hayden), pp. 427-533 (457, 458, 

 463, 464), pis. 1-8. 



1874b. On the homologies and origin of the types of molar teeth of Mam- 

 malia educabilia. Journ. Acad. Nat. Sci. Philadelphia, ser. 2, vol. 8, 

 pp. 71-89 (78), 29 figs. (fig. 5). 



1884. The Vertebrata of the Tertiary formations of the West. Book L Rep. 

 U. S. Geol. Surv. Terr. (Hayden), vol. 3, pp. i-xxxiv, 1-1009 (343, 

 344), figs. 1-38, pis. i-7Sa (57, 57a). 



61 Illustrated in Peterson, 1931b, fig. 12; and Scott, 1945, pi. i, figs. 4, 4a. 



