PLATE XXXIII. 



Unio Eoanokoides Lea '^^"^ 



""""" •*•-•• •----. .... .... .... ...... .... .... .... ...... . ^4h 



Fig. 1. Left view of a specimen of the prevailing fo¥m. 



2. Left view of another specimen, showing less arcuatiou of the hinge-line and a 

 more quadrangular form. See outline, Fig. 3, Plate XXXI. 



Unio alatoides Lea 



. '''"""'"'""""*"""'*"*""""■"""""-"-•*---•-------•••••»••-...... 249 



Fig. 3. View of a specimen of this species, showing a portion of the posterior alation. 

 4. View of another specimen differing in size and in the curvature of the basal line. 

 334 



