PLATE XXIX. 



PAGK 

 Fig. 1. TUEBONILLA POTOMACENSIS n. sp 155 



2 miles below Potomac Creek. 



Fig. 2. Tuba maeylajstdica n. sp 155 



Mouth of Paspotansa Creek. 



Fig-. 3. Odostomia tkapaquara (Harris) 156 



Potomac Creek. 



Fig. 4. Niso umbilicata (Lea) 156 



Potomac Creek. 



Fig. 5. GiBBLiLA GLANDULA (Conracl) 157 



Potomac Creek. 



Figs. 6, 6a. FissuKiDEA maeleokoensis n. sp 158 



6. Lateral view of type specimen. Upper Marlboro. 

 6a. Dorsal view of same specimen. 



Fig. 7. Dentalium inNUTiSTEiAXUM Gabb 158 



Popes Creek. 



Fig. 8. Dentalium mississippiensis Conrad 159 



Upper Marlboro. 



Fig. 9. Cadulus abeuptus Meyer and Aldrich 159 



Woodstock. 



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