PLATE 23. 
Fic. 1. CoRBICULA CLEBURNI...... 4-26. .-ccce fi Re LO ea c/a eC OG a 
a. Interior view, right valve; natural size. 
b. Exterior view of the same. 
c. Exterior view of another example. 
All of natural size; but the species reaches a larger size than any 
of those figured. 
Fic. 2. CORBICULA (LEPTESTHES) FRACTA..---..--. Usa Ge ae oO Sa 
a. From a drawing by Mr. Meek of an example from Hallville. 
b. Example from Black Buttes Station; left side view ; natural size. 
ce. Dorsal view of the same. 
d. Right side view of a young example; from the same locality. 
e. Dorsal view of the same. 
For another figure of this species see plate 21. 
Fic. 3. CORBICULA OBESA....-.....- SCN S18 HL Ne PR Ge SUA We ce I A 
. Left side view of an example rather above the average size. 
. Dorsal view of the same. 
Right side view of another example. 
. Front view of the same. 
. Dorsal view of the same. 
All of natural size. 
eaecs 
Fic. 4. CoBRICULA (LEPTESTHES) MACROPISTHA ..---....---.---- ndco boon so60 
a. Left side view; natural size. 
b. Dorsal view of the same. 
e. Left side view of another example. 
d. Dorsal view of the same. 
e. Interior view of left valve. 
Jf. Interior view of the right valve of another, a larger, example. 
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