PLATE LI. 
PAGE 
Figs. 1-3. Typhis acuticosta Conrad 201 
1. Dorsal view. Cove Point. 
2. Ventral view. Same locality. 
3. Ventral view. Plum Point. U. S. National Museum. 
Pigs. 4-6. MuRiciDEA SHiLOHENsis (Hellprln) 202 
4. Ventral view. Plum Point. Cornell University. 
5. Ventral view of another specimen. Same locality. 
6. Ventral view of another specimen. Same locality. 
Figs. 7a, 7b. Tbophon tetricus Conrad 202 
7a. Dorsal view. St. Mary's River. 
7b. Ventral view of same specimen. 
Fig. S. Trophon tetricus var. levis n. var 203 
8. Ventral view. St. Mary's River. 
Figs. 9, 10. Tbophon chesapeakeanus n. sp 203 
9. Ventral view of young individual. St. Mary's River. 
10. Ventral view of adult. Same locality. 
Figs. 11-13. ScALASPiKA strumosa Conrad 204 
11. Ventral view. Yorktown, Virginia. 
12. Ventral view.- St. Mary's River. 
13. Ventral view. Cove Point. 
Figs. 14, 15. Ukosaxpinx cinebeus (Say) ? 205 
14. Ventral view. Cove Point. 
15. Dorsal view of another specimen. Same locality. 
Figs. 16, 17. Ubosalpinx eusticus (Conrad) 206 
16. Ventral view. St. Mary's River. 
17. Ventral view. Cove Point. 
Pigs. 18-20. CORALLIOPHILA CUMBERLANDIANA (Gabb) 211 
18. Dorsal view. St. Mary's River. 
19. Ventral view. Same locality. 
20. Dorsal view. Same locality. 
