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University of California Publications in Geology [Vol. 10 



A single fragmentary upper cheek-tooth (no. 1323) from beds pre- 

 sumed to belong to the Orinda Pliocene near Bolinger Canyon, Cali- 

 fornia, shows the approximate form and dimensions of upper cheek- 

 tooth of N. g. tehonense from the Tejon Hills. This specimen has been 

 referred to as representing a Hipparion-like type distinct from two 

 larger forms known from the Orinda." It is possible that specimen 

 1323 represents a species in or near N. g. tehonense. 



Several lower cheek-teeth from the Chanac formation of the Tejon 

 Hills represent small Hipparion forms. It is possible that more than 

 one species is present. If so the larger teeth as no. 21784 and 21785 

 (figs. 4 and 5) presumably represent N. g. tehonense, and the smaller 

 specimens, as no. 22364 (fig. 6), might belong with the narrower 

 upper cheek-teeth approaching Neohipparion niolle. The small lower 

 cheek-teeth from the Chanac formation approach the characters of a 

 small Hipparion specimen (no. 22387) from the Ricardo beds above 

 the uppermost basalt in the type section. 



A lower cheek-tooth figured in the first discussion of the Tejon 

 Hills fauna 7 corresponds to the smaller of these two faunas. 



NEOHIPPARION, near MOLLE Merriam 

 A second upper molar, no. 21781 (fig. 3) from the Tejon Hills 

 shows a much narrower crown, narrower fossettes and a flatter proto- 

 cone than the specimen distinguished as Neohipparion gratum tehon- 

 ense. In width of crown and narrowness of fossettes this specimen 

 approaches Neohipparion ) nolle" of the North Coalinga Jaealitos- 

 Etchegoin section, but the protoeone is narrower anteroposteriorly. 

 In character of protoeone no. 21781 is intermediate between N. molle 

 and N. g. tehonense. 



A 1VP (figs. 9a and 9b) evidently representing Neohipparion molle, 

 obtained by R. W. Pack of the Geological Survey from beds overlying 

 strata referred to the San Pablo, one mile north of Ingram Creek, on 

 the east flank of the foothills of the Mount Diablo Range, shows the 

 protoeone a little narrower anteroposteriorly than in the type of N. 

 ■molle. As the type of N. molle and the specimen found by Mr. Pack 

 both represent 1VP, it is possible that since the Tejon Hills specimen 

 no. 21781 is a M 2 it may also belong in N. niolle, as the protoeone of 

 M- is commonly shorter anteroposteriorly than in M^. 



« Merriam, J. C, Univ. Calif. Publ., Bull. Dept. Geol., vol. 7, p. 37(1, fig-. 2, 1913. 

 - Merriam, J. 0., Univ. Calif. Publ., Bull. Dept. Geol., vol. 8, p. 286. 

 s See Merriam, J. C, Univ. Calif. Publ., Bull. Dept. Geol., vol. 9, p. 3 and 

 fig. 2, 1915. 



