﻿38 LAMPSILIS 



Small, obovate, beak sculi)ture doubly looped. 



Gr. of L. amygdalum. 

 Shell more or less dorsally winged when perfect. 

 Thin, decidedly gaping in front and behind. 



Subintlated, dark, shining. Gr. of /,. ainphichcrna. 



Compressed, dull colored. Gr. of L. leptodon. 



Shell inflated. 



Thin, beaks smooth, feebly rayed. Gr. of L. saladoensis. 

 Solid, scarcely dimorphic. Gr. of L. utnhrosa. 



I.arge, obovate, strong-ly winged. 



Strongly dimorphic, shell dark. Gr. of L. aluta. 



Scarcely dimorphic, thin. Gr. of L. gracilis. 



Shell of medium size. 



Obovate, bright copper-colored, subinflated. 



Gr. of L. metalUca. 

 Compressed, with a strong dorsal wing. 



Gr. of L. scutulata. 



Subgenus Lampsilis s. s. 



Shell inflated, rather thin, shining, sometimes having a pos- 

 terior ridge ; beak sculpture coarse, consisting of a few more 

 or less parallel ridges, which scarcely fall into loops. Animal 

 having the mantle of the female usually toothed and thick- 

 ened on the post-basal portion, which develops into a large, 

 curious flap when the gills are filled with ova. 



Type: Unio ovatus Say. 



Lampsii.is \kntricosa (Rames). 



Shell large, rather solid, obovate, inflated, with very full, 

 high beaks, which have a few coarse, irregular corrugations 

 that are inclined to be doubly looped ; surface generally nearly 

 smooth, the rest periods well marked ; e])idermis normally 

 shining, greenish, greenish-yellow or brownish with broad, 

 bright green rays. In old shells the rays are often nearly or 

 (|uite wanting. Hinge line usually incurved in front of the 

 beaks and outcurved l>ehind them ; ligament large and prom- 

 inent, extending under the beaks, and narrow in front of theiii. 



