PLATE C. 
PAGE 
Fig. 1. Pecten (Chlamys) mauisokius Say 377 
1. Exterior of left valve. Flag Pond. x % 
Fig. 2. Pecten (Chlamys) jeffersonilts Say 378 
2. Exterior of right valve. St. Mary's River. X Vz 
Fig. 3. Pecten jeffersonius var. edgeoombensis Dall 379 
3. Exterior of left valve. St. Mary's River. U. S. National 
Museum. X % 
Fig. 4. Pecten jeffersonius var. septenarius Say 379 
4. Exterior of right valve. Petersburg, Virginia. U. S. National 
Museum. x % 
Figs. 5a, 5b. Ostrea sell5:formi.s var. thomasii (Conrad) 380 
5a. Exterior of type specimen. Charles county near the Patuxent 
river. Acad. Nat. Sci., Phila. 
5b. Interior of the same specimen. 
