PLATE LXXI. 
PAGE 
Fig. 1. Spisula (Hemimactra?) chesapeakensis n. sp 290 
1. Exterior of right valve. 3 miles north of Plum Point, x % 
Figs. 2, 3. Exsis direc tu.s (Conrad) 291 
2. Interior of left valve. Yorktown, Va. 
3. Exterior of right valve. Same locality. 
Figs. 4-G. Ensis ensiformis Conrad 292 
4. Posterior portion of broken valve. St. Mary's River. 
5. Posterior portion of broken valve. Same locality. 
6. Interior of left valve. York River, Va. 
Figs. 7a, 7b. Psammobia gubernatoeia n. sp 292 
7a. Interior of left valve. Jones Wharf. 
7b. Exterior of same valve. 
Figs. 8, 9. Asaphis centenaria (Conrad) 293 
8. Interior of left valve. Jones Wharf. 
9. Exterior of left valve. Same locality. 
