ANODON.—Ptare XII. 
ared postangulari elevata, compressa, cuneatd, margine 
laterali perobliquo, margine terminali oblique trun- 
cato, margine venirali convexo, ad terminum sursum 
acclivi, medio oblique contracto, umbonibus planulatis, 
lenué undulatim rugatis. 
THE PLAIN ANoDON. Shell thin, inflated, pale straw- 
coloured, smooth, contracted in the middle, com- 
pressed, irregularly oval; posterior side elongated, 
biangular, postangular area elevated, compressed, 

cuneate, lateral margin very oblique, terminal mar- 
gin obliquely truncated, ventral margin convex, slop- 
ing upwards at the end, middle obliquely contracted, 
umboes flattened, finely undulately wrinkled. 
PARREYSS. 
Hab, ——? 
The umboes are prettily ornamented with undulated 
wrinkles in radiating rows. 

