PLATE XCIX. 



PAGE 



Fig. 1. Pecten (Amusium) mortoni Ravenel 372 



1. Exterior of right valve. Fort Thompson, Florida. U. S. National 



Museum. x % 



Fig. 2. Pecten (Pseudamusium) cerixus Conrad 373 



2. Exterior of right valve. Plum Point. 



Fig. 3. Pecten (Chlamys) coccymelus Dall 374 



3. Exterior of left valve. Plum Point. (After Dall.) 



Fig. 4, Pecten (Chlamys) rogersi Conrad . : 375 



4. Exterior of right valve. Near Skipton. U. S. National Museum. 



Fig. 5. Pecten (Chlamys) clintonius Say 375 



5. Exterior of right valve. James River, Virginia. x % 



Fig. 6. Pecten (Chlamys) marylandicus Wagner 376 



6. Exterior of left valve. Jones Wharf. 



