1915.| Matthew and Granger, Lower Eocene Wasatch and Wind River Faunas. OL 
Bull horizon of the Bighorn Wasatch. Several hundred specimens are at 
hand for comparison showing a considerable range in size, and variation in 
various characters, but fairly constant in those cited above. 
Hyopsodus mentalis Cope 1875. 
Antiacodon mentalis Corr, 1875, Syst. Cat. Eoc. Vert. New Mex., p. 17; (Sarcole- 
mur) 1877, Rep. Vert. Foss. New Mex., p. 149, pl. xlv, fig. 15. - 
Syn., Hyopsodus lemoinianus Corer, 1882, Proc. Am. Phil. Soc., Vol. XX, p. 148; 
Tertiary Vertebrata, p. 236, pl. xxive, fig. 9— OsBorn, 1902, Bull. A. M. N. H., 
Vol. XVI, p. 183, fig. 7— Loomis, 1905, Am. Journ. Sci., Vol. XIX, p. 420, fig. 3. 
Type, a lower jaw fragment with m,-2, figured by Cope in 1877. Not 
found in National Museum collection. | ; 
No. 16194, upper and lower jaws, from the upper horizon (Largo beds) 
Fig. 5. Hyopsodus mentalis Cope, topotype, upper and lower jaws, No. 16194. Crown 
views of upper and lower teeth and external view of lower jaw fragment all enlarged to 
three diameters. Largo beds, Ojo San Jose, Wasatch of New Mexico. 
