106 CAM^ENA. 



minutely granular. Peristome well reflexed, the baso-columellar 

 margin toothed. Embryonal shell smooth, tvvo-whorled, between 

 one-sixth and one-seventh the diameter of the adult, its junction 

 with the after growth indicated by a widening of the whorl. Type 

 C. platyodon Pfr., pi. 19, fig. 10. 



Animal resembling Camsena. Sole very indistinctly tripartite, the 

 edges of foot lacking all appearance of a foot-margin ; sides irregu- 

 larly granulated; tail rounded above, with a median, impressed lon- 

 gitudinal line, which does not extend quite to the tail. 



Jaw strong, dark orange colored, having eight strong ribs (pi. 39, 



fig. 3). 



Central and lateral teeth of the radula (pi. 39, fig. 1) having a 

 single large cusp, which extends about to the posterior edge of the 

 basal plate. Marginal teeth (pi. 39, fig. 2) becoming quadri-cuspid, 

 by the splitting of both mesocone and ectocone. 



Genital system (pi. 39, fig. 4) having a very short vestibule. 

 There is no dart-sack or other accessory gland upon the female side ; 

 spermatheca duct very long, without diverliculum. Penis stout, 

 exhibiting, when cut open (fig. 5), a very large penis-papilla; from 

 the apex of the penis arises the slenderer epiphallus, which receives 

 the penis retractor at the middle, the vas deferens at the fourth of 

 its length ; beyond the insertion of the vas deferens it is continued 

 in a short flagellum. 



In anatomy, Camcenella platyodon resembles Camcena in all 

 respects save that the penis-papilla is larger (a trifling difference) 

 and the cusps of the marginal teeth are much shorter. The shell 

 has a smaller nucleus than in Camtena more as in Obb, but not 

 so indistinctly defined ; and the maculated white and brown colora- 

 tion and deflexed last whorl are also as in Obba. It differs from 

 Obba in lacking an appendix on the penis, and in the ribbed jaw. 



C. platyodon Pfr., vi, 239. Island of Hainan. 

 tonrnoueri Crosse. 



Subgenus NEOCEPOLIS Pilsbry, 1891. 



Neocepoli* PILS., Man. of Conch, vi, p. 235, type H. merarchu. 



Shell globose, solid, narrowly umbilicated, with elevated spire and 

 narroiv, sloivly ividening whorls, the lad deflexed in front. Aperture 

 truncate-rounded, the entire lip reflexed, its ends joined by a callus. 

 Columelbi <li/ated, thickened and obtusely toothed within. Typically 



