52 



University of California Publications in Geology [Vol. 9 



Measurements of Type Specimen, No. 21400 



Length, anterior side P 2 to posterior side M 3 146 mm. 



Length, anterior side P 2 to posterior side P 4 78.8 



Length, anterior side M 1 to posterior side M 3 67. 



P 2 , anteroposterior diameter 29.8 



P 2 transverse diameter 18.5 



P 3 , anteroposterior diameter 24.5 



P 3 , transverse diameter 22.7 



P 3 , height of somewhat worn crown 44. 



P 4 , anteroposterior diameter : 24.9 



P 4 , transverse diameter 21. 



M 1 , anteroposterior diameter 24. 



M 2 , anteroposterior diameter 24. 



M 2 , transverse diameter 21.7 



M 2 , height of crown 43. 



M 3 , anteroposterior diameter a 22. 



M 3 , transverse diameter a 18. 



a, approximate. 



PEOTOHIPPUS TEHONENSIS, n. sp. 



Type specimen an upper molar, no. 21779, from the Tejon Hills, southern 

 end of San Joaquin Valley, California. 



Upper molar crown strongly curved and well cemented; outer styles of 

 moderate strength; protocone considerably flattened transversely and connected 

 with the protoconule by a wide isthmus; fossettes wide transversely and show- 

 ing plication of enamel only on the adjacent borders. 



Pigs. 4a to 4c. Protohippus tehonensis, n. sp. M 1 ?, type specimen, no. 21779, 

 from the Tejon Hills, southern end of the San Joaquin Valley, California. Fig. 

 4o, occlusal view; fig. 4b, outer view; fig. 4c, posterior view. 



