CYCLOSTREMA. 89 



C. CANCELLATA, Marrvatt. PL 31, figs. 27, 28. 



White, sublenticular, flattened convex above, more convex below, 

 with oblique radiating riblets, interrupted by an obtuse peripheral 

 rib, the interstices of the riblets finely sj^irally striated, umbilicus 

 moderate. Diam. 6 mill. 



West Indies; Philippines f 



C. EBURNEA, Nevill. PI. 31, figs. 29, 30. 



Narrowly umbilicated, thick, white, shining, longitudinally ob- 

 liquely plicate, the interstices spirally striated, suture narrowly mar- 

 gined, periphery with a corded carina, bordered by an impressed 

 line above and below, base sculptured like the upper sui-face. 



Diam. 4'75 mill. 



Pooree, Bay of Bengal. 



The Philippine specimens referred to C. concellata, ]\Iarryatt by 

 Sowerby, may prove to belong to this species. 



C. ALVEOLATA, Jousseaumc. PI. 31, figs. 31, 32. 



Depressed, widely umbilicated, rather thick, transparent, vitreous 

 white, with an occasional spiral ridge, between which are radiating 

 riblets, both above and below, the interstices spirally striate. 



Diam. 1-5 mill. 



Hub. unknown. 



C. ScHRAMMii, Fischer. PI. 31, fig. 33. 



Subdepressed, spire rather flattened, whorls excavated below the 

 suture, with strong, oblique, sharp radiating ribs. 



Diam. 3*5 mill. Isl. Guadeloupe, West Indies. 



C. Archeri, Tryou. PI. 33, fig. 84, ^r). 



Rather widely umbilicated, shell depressed, spire scarcely elevated, 

 whorls rounded, with regular convex longitudinal ribs, the inter- 

 stices finely spirally lirate, peristome thickened. Diam. 2"5 mill. 



Singapore (Archer). 



C. Ammoxoceras, a. Ad. PI. 31, figs. 34, 35. 



Depressed, spire slightly elevated, la.st Avhorl flattened near the 

 suture and around the moderate umbilicus, with rather thick, dis- 

 tant longitudinal ribs, the interstices finely spirally striated, aperture 

 large, outer lip thin. Diam. 3 mill. 



Japan. 



Less depressed, with more distant and prominent ribs than the 

 preceding species; diflers also in the thin peristome, and sutural 

 and basal flattenino; of the bodv whorl. 



