112 PALAEONTOLOGY OF CALIFORNIA. 



C. pinguis, n. s. 



PI. 29, Fig. 221, and 221 a, b. 



Shell robust, subglobose when young, ovoid when adult; 

 spire moderately high; whorls probably as many as seven or 

 eight, very convex; suture strongly marked. Aperture rounded, 

 rapidly narrowed above; mature outer lip unknown; inner lip 

 heavily incrusted, bearing an obtuse, angular prominence above, 

 and two strongly marked, acute folds below, the lower of which 

 is prolonged downwards, and becomes continuous with the an- 

 terior margin of the mouth. Surface marked by a series of 

 square, revolving ribs, with interspaces larger than the ribs 

 themselves; these are crossed by crowded and prominent lines 

 of growth. 



Figures of the shells magnified, the larger to a little over twice natural size ; 

 that of the immature shell, three diameters. Figure of the surface to show the 

 details of ornamentation. 



Locality: A very few specimens of this species have been found by Mr. Mathew- 

 son in the Bluffs, a mile west of Martinez (in Division A.?). 



A few specimens have been found at Martinez and at Tuscan Springs, which 

 may belong to this genus, or to Ringicula; but, on account of their imperfect 

 condition, I am not yet able to make out with any certainty either their generic 

 or specific relations. They seem to indicate two or even three species. 



RINGICULA, Desh. 



R. varia, n. s. 



PI. 29, Fig. 222 a, b. 



Shell small, elongate-ovoid; spire high; whorls six, slightly 

 convex; suture well-marked; body whorl broadly and regularly 

 convex. Aperture wide, acute behind, narrowed in front, and 

 with a deep, oblique notch. Outer lip nearly simple, the margin 

 being not twice as thick as the shell behind it, and very narrow ; 

 inner lip covered with a small, circumscribed callus, bearing two 

 small acute folds anteriorly. Surface variable, sometimes almost 



