PLATE LXXXIV. 
PAGE 
Fig. 1. DosiNiA ACETABULUM Conrad 315 
1. Interior of left valve. St. Mary's River. 
Figs. 2, 3. IsocAErjiA markoisi Conrad 316 
2. Exterior of right valve. Plum Point. 
3. Interior of left valve. Same locality. 
Figs. 4, 5. ISOCARDIA MAZLEA n. sp 317 
4. Exterior of right valve. Plum Point. 
5. Interior of left valve. Same locality. 
