CYPR-ffilD^E. 163 



Section III. (Luponia, Gray, pars.) 



Shell pyriform or pyriformly ovate, usually spotted. 

 Group A. Shell smooth, not margined. 



* More or less ventricose or inflated. 

 ** More or less oblong or sub-pyriform. 



Group B. Shell smooth, margined. 



* Margins not pitted. 



** Margins more or less pitted, dorsal spots usually 



ocellated. 



Group C. (Gaskoinia, Roberts.) Shell smooth, edentulate. 

 Group D. (Cypneovula, Gray.) Shell ribbed transversely. 

 Group E. (Pustularia, Swn.) Shell pustulate or nodulous. 

 Section IV. (Epona, H. and A. Adams.) 



Shell globose, back either smooth or with devated 

 tubercles, extremities produced. 



Subgenus TRIVIA, Gray. 



Shell subglobular, cross-ribbed, front of columella internally 

 concave, ribbed. 



Group A. Shell generally thin, aperture wide, outer lip narrow, 



margined. 

 Group B. Shell thick, usually margined, aperture narrow and 



more or less central. 



a. Having a dorsal impression. 



* Shell white. 



** Shell usually pinkish, spotted. 

 ** * Shell brownish. 



b. Having no dorsal impression. 



* Shell white. 



** Shell pinkish, sometimes spotted. 

 ** Shell brown. 



The material of this monograph has been prepared under some 

 disadvantages, during the few odd hours of leisure occurring in 

 an active mercantile life ; this will explain, if it does not excuse 

 its errors and omissions. The author takes this opportunity to 

 acknowledge valuable aid rendered by a number of conchological 

 friends at home and abroad, while prosecuting this labor of love. 



