22 PALAEONTOLOGY OF CALIFORNIA. 



VENUS, L. 

 V. Kennerlyi, Rve. ? 



i > 



PL 5, Fig. 37. 



Shell thin, subcompressed, rounded-subtriangular ; beaks 

 small, prominent, anterior; anterior and posterior ends about 

 equal ; base broadly rounded ; posterior cardinal margin sloping 

 convexly. Lunule small, elongate cordiform, flat. Surface marked 

 by numerous irregular concentric undulations and fine striae; 

 internal margin entire, not crenulated. Pallial sinus deep, ob- 

 lique, and narrow at the base. 



Figure, natural size. 



Locality and position : From the Miocene, at Griswold's, on tho road to New 

 Idria, Monterey County. 



I have not had an opportunity of examining Eeeve's figure or description of his 

 species, and from the very meagre note on the species in Carpenter's last Brit. 

 Ass'n Catalogue, I am unable to determine whether this should be referred to V. 

 Kennerlyi, or not. Should it prove distinct, I propose the name of V. pertenuis. 



MERCENARIA, Schum. 



M. PERLAMINOSA, Con. 



PI. 5, Fig. 38. 



(M. perlaminosa, Con. ; Proc. Phila. Acad. Nat. Sci., 1855, p. 267.) 



Shell, large, thick, rounded subquadrate, very inequilateral; 

 beaks anterior; anterior end excavated under the beaks, rounded 

 below; base broadly rounded; posterior end convexly truncated; 

 cardinal margin slightly convex. Surface closely marked by nu- 

 merous prominent, recurved, lamelliform concentric ribs. Lunule 

 marked by an impressed Hue. Hinge robust. Pallial line strong, 

 sinus small, oblique, acut*> at the base; muscular scars nearly 



