TERTIARY FOSSILS. 9 



CUMA, Humph. 



C. BIPLICATA, n. S. 

 PI. 2, Fig. 14. 



Shell small, thick, angular; spire elevated; sides nearly 

 straight, about as long as the mouth, in very old specimens a 

 little longer; whorls five and a half to six, the first two smooth 

 and round, the others concave and sloping above; suture faint. 

 covered by a thin layer from the succeeding whorl; body whorl 

 prominent and subangulated in the middle, bordered by a marked, 

 angular rib at the top, which passes up on the preceding whorls; 

 ornamented on the sides by about twelve short longitudinal no- 

 dose ribs, and by about eight or nine smaller revolving ribs, the 

 uppermost of which crosses the top of the longitudinal ribs; 

 these revolving ribs become fainter in front, until on the ante- 

 rior fourth of the shell they are nearly obsolete. Aperture broad, 

 angular above; columellar lip heavily incrusted; outer lip simple; 

 canal slightly bent. Umbilicus broad, imperforate, bordered by 

 two very strong oblique revolving ridges; anterior sinus deep, 

 narrow, and oblique. 



Figure, natural size. 



Locality and position: Not rare in the Miocene, south of Martinez, where it has 

 been collected by Mr. Mathewson and Mr. Voy. 



ANCILLARIA, Lam. 



A. Fishii, n. s. 



PI. 2, Fig. 15. 



Shell small, broad; spire high; whorls six; suture covered. 

 Aperture narrow, acute posteriorly, broad in advance; inner lip 

 moderately incrusted, with a single small fold in advance; outer 

 lip acute, anterior sinus deep. 



PAL. VOL. II. — 3 



