82 Bulletin 9 374 



Explanation Plate 4. 



(10) 



Page. 

 Ostrea trigonalis var. sylvcsrupis 38, 330 



Showing exterior of large incrassated valves 

 of this species as obtained from bed 8 at Woods 

 bluff, Torabigbee river. See page 38. The 

 work of boring mollusca is very apparent in the 

 large left valve. Engraved by the Albany 

 Eng. Co. 



