168 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Psammobia martini, new species 

 PI. 27, Figs. 7a and 7b 



Shell elongate, flat; nearly flat posterior slope meeting disk 

 of shell along a convex umbonal slope ; anterior dorsal slope but 

 slightly excavated under beak sloping less steeply than the pos- 

 terior dorsal margin. 



Dimensions: — Convexity, 5 mm. 



Type: — No. 389, Cal. Acad. Sci. Locality 181, near Vader, 

 Lewis County, Washington, on the east bank of the Cowlitz 

 River, just back of the Greeco ranch house, about four miles 

 east of Vader. Colls., F. M. Anderson and Bruce Martin. 



Named for Mr. Bruce Martin, who collected the type of this 

 species. 



Astarte perrini, new species 



PI. 27, Figs. 8a and 8b 



Shell quadrate with prominent, sharply pointed beak which is 

 one-third of shell length from acutely rounded anterior; pos- 

 terior margin truncate; ventral margin broadly arcuate; pos- 

 terior dorsal margin straight with gentle slope from beak to 

 posterior; anterior dorsal slope concave with elongate narrow 

 fairly distinct lunule ; escutcheon indefinite. 



Dimensions: — Length, 15.5 mm.; height, 13 mm.; convex- 

 ity, 3 mm. 



Type: — No. 390, Cal. Acad. Sci. Locality 181, near Vader, 

 Lewis County, Washington, on the east bank of the Cowlitz 

 River, just back of the Greeco ranch house, about four miles 

 east of Vader. Colls., F. M. Anderson and Bruce Martin. 



Named for Professor James Perrin Smith of Stanford Uni- 

 versity. 



Corbula cowlitzensis, new species 



PI. 28, Figs. 3a, 3b and 3c 



Shell small, thick, equivalve with inconspicuous beak; an- 

 terior dorsal margin convex, sloping steeply to an acutely 

 rounded anterior; ventral margin very broadly rounded; pos- 

 terior slope, a triangular area with apex at beak, nearly flat, 

 shallowly grooved and separated from the rest of the shell by a 

 very sharp ridge which extends from the beak to the posterior 

 end. 



