376 University of California Publications in Geology [Vol. 7 



the better preserved tooth from Bolinger Canon (no. 1324) seem 

 to represent different species. The second specimen (no. 1323) 

 from near Bolinger Canon is imperfectly preserved, but is pos- 

 sibly different from the other two teeth. 



NEOHIPPARION, sp. 



Specimen no. 19830, from Orindan beds two and one-half 

 miles southwest of Tassajara Post Office. 



This form is represented by a single tooth, P 2 (figs, la to lc). 

 The crown is rather large, it has been well cemented, and the 

 .outer styles are strong. The flattened protocone is distinct 

 almost to the base. The anterior and posterior fossettes are 

 narrow transversely, and the borders are formed into numerous 

 deep plications. The two fossettes are lightly connected. If 

 this connection is due to lack of wear, it is evident that the crown 

 was not greatly elongated. 



This tooth does not agree closely with any form known to the 

 writer, but it does not seem desirable with the present material 

 to give it a special designation other than to recognize it as a 

 distinct form. A species of Neohipparioii apparently different 

 from that from near Tassajara is known from late Tertiary beds 

 near Ricardo Post Office on the northwestern boundary of the 

 Mohave Desert. 



Measurements of Cheek-Tooth No. 19830 



P2, greatest anteroposterior diameter of crown 



P-, greatest transverse diameter of crown 



P-, anteroposterior diameter of protocone 



HIPPARJON(?) OR NEOHIPPARION 



Specimen no. 1324, from Orindan beds near Bolinger Canon. 



A fragmentary tooth (no. 1324, figs. 3a and 36) differs from 

 that seen in the form from Tassajara Canon in the round 

 protocone and more pronounced plication of the walls of the 

 anterior fossette. This type does not differ greatly from one 

 of the Neohipparion specimens from near Ricardo on the Mohave 

 Desert. 



25.8 mm. 

 21.6 

 8.2 



