400 University of California Publications in Geology [Vol. 12 



Measurements 



Premolars: No. 23212 No. 23223 



Anteroposterior diameter 24.2 mm. 26.3 mm. 



Transverse diameter 15.4 15.5 



Anteroposterior length of metaconid-metastylid 



column 13.8 15.1 



Molars: No. 23295 No. 232.32 



Anteroposterior diameter 25.8 24.5 



Transverse diameter 16 17.5 



Anteroposterior length of metaconid-metastylid 



column 14.5 15 



LOWER CHEEK TEETH, NEAE ( ?)PLIOHIPPUS EDENSIS 



These teeth are of narrow transverse diameter, and moderate size. 



Material—Molars, no. 23296 (figs. 148a-1486), no. 23298 (fig. 150a), no. 24229 

 (fig. 150b); and last molars, nos. 23293, 23297 and 23291 (figs. 151a, b, c) , all 

 from general Univ. Calif, loc. 3269. All in Univ. Calif. Coll. Vert. Pal. 



Pigs. 148a to 1516. ITliohippus edensis, n. sp. Narrow type of cheek teeth; 

 occlusal views, X 1; outer views, X Pigs. 148a, 148b, molar, no. 23296. 



Figs. 149a, 1496, molar, no. 24228. Figs. 150a, 1506, nos. 23298, 24229'. Figs. 

 151a to 151c, M5, nos. 23291, 23293, 23297. Eden beds, California. 



Characters. — The medium size, accompanied by transverse narrow- 

 ness of the crown, and the great convexity of the inner margin of the 

 protoconid and hypoeonid. 



Description.- — Several of the teeth are considerably worn. The 

 specimens all have the character of molars, being thickest transversely 

 at the anterior corner, and having the deep production of the fold 

 between the protoconid and hypoeonid. A specimen representing 



i 



