PLATE LXIII. 
PAGE 
Pigs, la, lb. PissuKiDEA ALTicosTA (Conrad) 266 
la. Dorsal view. St. Mary's River. Wagner Free Institute of 
Science. . 
lb. Lateral view of the same specimen. 
Figs. 2, 3. FissuRiDEA gbiscomi (Conrad) 267 
3a. Dorsal view. Church Hill. 
2b. Lateral view of the same specimen. 
3a. Dorsal view of young individual. Same locality. 
3b. Lateral view of the same specimen. 
Pigs. 4a, 4b. PissuRiDEA MARYLANDicA (Conrad) 268 
4a. Dorsal view. Plum Point. 
4b. Lateral view of the same specimen. 
Pigs. 5a, 5b. Fissubidea nassuia (Conrad) 268 
5a. Dorsal view. Jones Wharf. 
5b. Lateral view of the same specimen. 
Pig. 6. PissuKiDEA REDiMicuLA ( Say) 269 
6. Lateral view of type specimen. St. Mary's River. British 
Museum. (After Say.) 
Pigs. 7a, 7b. Emarginula marylandica n. sp 269 
7a. Lateral view. Greensboro. 
7b. Dorsal view of the same specimen. 
