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



PLATE 28 



Fig. 1. Ostrea lincolnensis Weaver, approximately X54- 



Fig. 2. Pecten branneri Arnold, X2. A young individual. 



Fig. 3a. Corbula cowlitzensis, new species, X3. Type ; a right valve. 



Fig. 3b. Corbula cowlitzensis, new species, X3. Hinge view of type. 



Fig. 3c. Corbula cowlitzensis, new species, X3. Left valve of cotype. 



Fig. 4a. Pitaria clarki, new species, XL Type. 



Fig. 4b. Pitaria clarki, new species, XL Hinge view of type. 



Fig. 4c. Pitaria clarki, new species, XL Hinge view of cotype. 



Fig. 5a. Spisula packardi, new species, XL Type. 



Fig. 5b. Spisula packardi, new species, XL Hinge view of type. 



