CRETACEOUS FOSSILS. 93 



angle and the anterior extremity. Surface ornamented by a row 

 of oblique nodes on the angle of the whorls, and by small ribs 

 above and below ; a single one, larger than the rest, bordering 

 the upper edge of the whorl, just below the suture; the ribs 

 above the angle are linear, those below are larger, subnodose, and 

 diminish in size anteriorly. The lines of growth arc faint. 



Length of the specimen, less the upper whorls, .5 inch; pro- 

 bable total length, .58 or .60 inch. 



A single specimen, found by myself, in an excavation above the "Clark" or 

 upper coal-vein, near Clayton, Contra Costa County (in Division B.). 



T. (S. G-. Drillia) varicostata, n. s. 



PI. 18, Pig. 47. 



Shell elongated, fusiform, spire high, whorls eight, subangu- 

 lar, suture indistinct ; surface marked by a few large, rounded, 

 oblique ribs, most prominent on the angle of the whorl, slightly 

 extended below, and becoming suddenly obsolete above ; these 

 are crossed by numerous linear ribs, largest on the most promi- 

 nent part of the whorl. Aperture elongated, widest above, and 

 rapidly narrowing below. Sinus broad, rounded, commencing 

 at the suture. 



Length, .6 inch. 



Locality: Same bed as the above, but in an adjoining hill. 



CORDIERA, Rouault. 



C. MICROPTYGMA, 11. S. 

 PI. 28, Fig. 203. 



Small, slender, fusiform ; spire high, composed of eight slightly 

 convex whorls ; suture sharply impressed. Aperture elongated, 

 subacute behind, prolonged below ; canal unknown ; inner lip 

 heavily incrusted ; columella curved, bearing four or five small, 

 rounded, oblique foldSj placed close together ; outer lip with the 



