396 PROCEEDINGS OF THE ACADEMY OF [1892. 



Bahamas and Florida Keys. The fossil species described by Dr. 

 W. H. Dall from Florida belong mainly to Plagioptycha. 



Genus GLYPTOSTOMA Binney & Bland. 



Genitalia : 9 system having an appendicula or a dart-sack 

 entering the vagina. Vas-deferens entering the penis at its middle. 



Jaw very low, broadly arched, having about sixteen strong sepa- 

 rated ribs. Dentition normal. 



Shell depressed, broadly umbilicated, having a simple, thin, acute 



lip- 



The single species known is G. neivherryammi W. G. Binn., of 

 San Diego, California. The shell is entirely Patuloid in form, but 

 not in texture. Its systematic position is doubtful. 



Genus ACANTHINULA Beck. 



Said to j^ossess a dart-sack and mucous glands, and probably to be 

 grouped here. 



Genus VALLONIA Risso. 



This genus of minute shells probably belongs here. A dart-sack 

 is present. 



Group III, TELEOPHALLA. 



Female genital system lacking all accessory organs ; male organs 

 complicated by the presence of a long flagellum and a well-devel- 

 oped appendix. 



Jaw thin, delicately plaited or distantly striated (or smooth ?). 



Besides the two genera given below, this group perhajis includes 

 Pararhytlda Ancey, an oxygnathous group. 



Genus SAGDA Beck. 



Genitalia : 9 system without accessory organs ; duct of the 

 spermatheca long. Ova rather large, few in number, with calca- 

 reous shell. S' system having a long penis at the apex of which 

 are inserted the retractor muscle, vas-deferens, and a long, folded 

 flagellum ; and at the middle of the penis is inserted a very long 

 but simple flagellum-like appendix.'' 



The jaw is thin, delicate, arched, composed of narrow vertical 

 plates soldered together. Dentition typically Helicoid. Foot long 

 and narrow. 



Distribution, Jamaica. 



i^See Pilsbry, Proc. A. N. S. P. 1892, p. 213, pi. 13. 



