EXPLANATION OF PLATE XXL 



Fig's 64 A and B. — EUiptio nigra (Raf.) cf, Meramec R., ISleramec 

 Highlands. 



Fig's 65 A and B. — E. nigra (Raf.) 9, Miss., Hannibal. 



Fig's 66 A and B. — E. dilatata (Raf.) 9, Osage R., Osceola. 



Fig's 67 A and B. — E. dilatata delicata (Simpson) 9 , White R., HoUistcr. 



Fig's 67 C and D. — E. dilatata delicata (Simp.) c?, Black R., Williams- 

 ville. 



Fig's 68 A and B. — E. dilatata subgibbosa (Lea) 9, Black R., Williams- 

 viUe. 



Fig's 68 C and D. — E. dilatata subgibbosa (Lea) d', Black R., Williams- 

 ville. 



Fig's 69 A and B. — Uniomcrus letralasmu (Say) 9, Batterton Pond, 

 Columbia. 



