25^ BULIvETiN 31 258 



PLATE 57 

 Figure Page 



1-6. Corbula coinprcssa Lea, Claiborne 187 



Fig. I, 5 mm. 



2, 6 " 



3. 4-3 " 



4, 4.8 " 



5. 6, X 4- 



7-9. Carbtila aldrichi Meyer, 7.5-8 mm 189 



From the Sabine stage, Woods Bluft", Ala. Notice the differ- 

 ence in the size of the valves, also strong, radiating striae. 



10-17. Corbula sinithvilleiisis Har 188 



Fig. 10, 7 mm. 



11, 7.5 " La. 



12-17 from Smithville, Tex. 



12, 5 mm. 

 13,8 " 



14, 6.2 " 



15, 7 " 

 16,5.5" 



17, 10.5 mm. 



18-21. Corbula rugosa Lam., Grignon, France 190 



Fig. 18, II. 5 mm. 



19, 10 " 



20, 8 

 21,9-5 " 



22-23. Corbula wailesiana Har., Jackson, Miss 1S9 



Figs. 22 and 23, each 13 mm. Here inserted to show rela- 

 tionship to Claibornian forms. 



24-28. Corbula texana Gabb, all from Texas 190 



Fig. 24, 10. 5 mm. 



25, 7.5 " Tex. State Mus. 



26, 6 



27, 7-5 " 



28, 7 



