PLATE XLII1. 



Fig. I. Pctricola Harrisii Dall ; 22.5 mm. ; Miocene of Virginia ; p. 1060. 



Fig. 2. Semele mutica, var. scintillata Dall; 8.0 mm.; Oligocene of Florida; p. 988. 



Fig. 3. Astarte protracta O. Meyer, young; Ion. 6.5 mm.; Claiborne sands, Claiborne. 



Alabama. 



Fig. 4. Semele alumcnsis Dall ; .8.5 mm. ; Alum Bluff Miocene ; p. 989. 

 Fig. 5. Diplodonta yorkensis Dall, view of interior and profile of teeth; ii.o mm.; 



Miocene of Virginia; p. 1185. 



Fig. 6. Semele Smithii Dall, restored from fragments ; 26.0 mm. ; Chipolan ; p. 987. 

 Fig. 7. Pteropurpura Postii Dall, Proc. U. S. Nat. Mus., xviii., p. 44, 1895 : Tampa 



silex beds ; Oligocene ; alt. 38 mm. 

 Fig. 8. Velorita Aoridana Dall ; 80 mm. ; Tampa silex beds ; Oligocene ; showing hinge 



as worked out. 



Fig. 9. Trapezium claibornense Dall ; 7.0 mm. ; Claibornian ; outside view. 

 Fig. 10. The same, view of the interior. 



Fig. it. Rochefortia Stantoni Dall; 3.76 mm.; Miocene of North Carolina; p. 1160. 

 Fig. 12. Semele mutica Dall, typical form ; 9.5 mm. ; p. 988. 

 Fig. 13. Velorita Aoridana Dall, profile of type specimen ; 80.0 mm. 

 Fig. 14. Plcurotoma Lapenotierei Dall ; Tampa silex beds at Ballast Point ; 27.0 mm. 

 Fig. 15. Meretrix (Callista) pittsburgcnsis Dall, view from above; 36.0 mm.; Eocene 



of Pittsburg, Oregon. 

 Fig. 16. Semele mutica, var. Stearnsii Dall; ii.o mm.; Chipolan Oligocene; p. 988. 



1199 



