36 PALEONTOLOGY OF CALIFORNIA. 



Figures, natural size. 



Localities and position: From the Miocene, one mile east of the Excelsior Mine, 

 Napa County, Prof. Whitney ; and twenty miles east of Clear Lake, on the road 

 from Colusa to the Hot Sulphur Springs ; Dr. George. 



MORRISIA, Davidson. 

 M. HORNII. 



PL 12, Fig. 63. 

 (M. Hornii, Gabb; Proc. Phila. Academy, 1861, p. 371.) 



SHELL minute, subcircular, flattened; beak acute; area narrow, 

 long; a faint sinus usually occupies the middle of the lower por 

 tion of the upper valve ; foramen large, acute above, and rounded 

 or subaugular in the upper valve. Surface, under a lens, presents 

 a minutely granular appearance. 



Figure, highly magnified. Length about .11 inch. 



Locality and position: From the Post-Pliocene marl at Santa Barbara; collected 

 by Dr. A. L. Heermann. This shell seemed to be abundant in the marl collected 

 by Dr. Heermann ; but I have never seen it among the shells collected by the Sur 

 vey in that vicinity or elsewhere, and failed to find it myself, on subsequently 

 visiting the locality. 



f 



ECHINODERMATA. 



CLYPEASTER, Lam. 

 C. GABBII. 



PL 12, Fig. 64, 64 a, 

 (C. Gabbii, K6mond; Proc. Cal. Acad., 1863, p. 63.) 



I ECHINARACHNIUS, Van Phels. 



E. BREWERIANUS. 



PI. 12, Fig. 65, 65 a. 

 (E. Brcwerianus, Remond; Proc. Cal. Acad., 1863, p. 63.) 



