348 University of California Piihlications in Geology [Vol. 12 



Lagomorpha 



HYPOLAGUS EDENSIS, n. sp. 



Type. — A fragment of the left mandible containing P3, Mj, and M2, no. 23376 

 (fig. 52), Univ. Calif, loc. 3269. Specimens tentatively referred to this species 

 are the portions of a premaxilla holding an incisor, no. 23375 (fig. 53), and a 

 small astragalus, no. 23377 (fig. 54), both from the same general locality as the 

 type. All specimens in Univ. Calif. Coll. Vert. Pal. 



Characters. — The depth of the two valley-like infoldings of the 

 exterior side of P^, the posterior of the two extending slightly over 

 half way across the crown. 



Fig. 52. Hypolagus edensis, n. sp. P3, Mj, and Mj, no. 23376, outer and 

 occlusal views, X 2. 



Fig. 53. .^Hypolagus edensis. Incisor, no. 23375, X 1. 

 Fig. 54. Lagamorph astragalus, no. 23377, X 3. 

 Fig. 55. Avian jihalanx, no. 599, X 2. 



All specimens from Eden beds, California. 



Description and comparison. — The specimen has the genral char- 

 acter of the genus Hypolagus as given by Dr. L. R. Dice;^' it differs 

 from the type species, H. vet us Kellogg, by the depth of the two 

 infoldings of the exterior tooth surface of P3. A single deep infolding, 

 as in H. veins, occurs in the exterior side of the associated molars. 

 The inner sides of the teeth are rounded and lack the reentrant angles 

 seen in H. vetus. The anterior portions of the crowns are higher than 

 the posterior. 



Measurements of Type Dentition, No. 23376 



P3, greatest anteroposterior diameter 2.4 mm. 



P5, greatest transverse diameter 2.1 



Mj, greatest anteroposterior diameter 2 



Ml, greatst transverse diameter 2.2 



Mj, greatest anteroposterior diameter 2.1 



Mj, greaetst transverse diameter 2.2 



37 Dice, L. R. Systematic Position of Several American Tertiary Lagamorphs. 

 Univ. Calif. Publ., Bull. Dept. Geol., vol. 10, pp. 181-183, 1917. 



