TERTIARY FOSSILS. 5 



Report, Vol. 5, J>1. 7, Fig. 63, from Ocoyo or Poso Creek, Tulare County, where 

 cabts were found. 



It is possible that the specimens figured as No. 67, on the same plate, under the 

 name of Natica geniculata, Con., may belong to this species, though the drawing 

 is too imperfect for a satisfactory determination. 



C. SINUATA, n. 8. 

 PL 1, Fig. 7. 



SHELL elongated, rather slender; spire low, convex; whorls 

 four; suture deeply channelled, bordered by a thickened rim; 

 body whorl convex in the middle, broadly grooved above, and 

 excavated below. Surface marked by numerous fine revolving 

 lines, and in the upper whorls by numerous radiating ribs. 

 Aperture long and narrow; columellar lip sinuous, slightly in- 

 crusted; outer lip simple; canal slightly recurved. 



Figure, natural size. 



Locality : From the Miocene of Walnut Creek, Contra Costa County. Rare. 

 But two specimens of this curious shell have been found ; one of which is of the 

 size figured, the other not more than half as large. 



PLEUROTOMA, Lam. 



Tunis, Bolt., not Humph. 



P. (SURCULA) CARPENTERIANA. 



PL 1, Fig. 8. 

 (P. (S.) Carpenteriana, Gubb; Proc. Cal. Acad. Nut. Sci., 1865, p. 183.) 



SHELL large, fusiform; spire about as long as the mouth; 

 whorls eight, subflattened- on the sides, slightly concave near 

 the suture, and very slightly convex below; suture impressed 

 Surface marked by numerous fine revolving ribs, rounded and 

 sometimes alternating in size, especially on the lower part of the 

 body whorl. Aperture narrow; inner lip faintly incrusted; outer 



