32 PROCEEDINGS OF THE ACADEM-Y OF [March^ 



more deeply concave inside, than that of C. campamdatus. The edge 

 is bevelled and flat between projecting outer and inner laminae. 



Alt. 8.5, diam. 12.2 mm.; whorls U. 

 " 7.1 " 10 " " d. 



Tanega-shima, Osmni. Types No. 94,711 A. N. S. P., from No. 54:b 

 of Mr. Hirase's collection. 



The Cycloti of this group, represented in Japan by C. campanulatus, 

 and in China by C. stenomphcdus and its allies, are very similar in shape 

 and color. The form described above is well distinguished by its 

 externally convex operculum, that of C. campanulatus being flat out- 

 side and much less concave within. 

 Spiropoma yakushimanum n. sp. 



The shell is depressed, very openly umbilicate, solid, yellowish- 

 olivaceous, somewhat brownish on the last whorl, the cuticle much 

 paler or usually wanting on the inner whorls. Surface glossy where 

 unworn, marked with growth-lines and very indistinct traces of spiral 

 strise. Whorls fully 4^, quite convex, the first one projecting a little; 

 last whorl tubular, very convex at the base, deeply descending in front. 

 Aperture oblique, longer than wide. Peristome contracted, being 

 thickened within and shortly built forward; obtuse, whitish. It is 

 thickened in the posterior angle, but usually has a small notch there. 

 The columellar margin recedes rather conspicuously. The short 

 parietal margin is thick and straight. 



Alt. 7.3, diam. 12.5, alt. of aperture including peristome 5.3, width 

 4.7 mm. 



Alt. 6.3, diam. 11.5 mm. 



The operculum is conic, composed of 7^ flat whorls separated by a 

 narrow ledge with raised outer edge, producing a narrow spiral channel 

 along the suture; summit obtuse. 



Yaku-shima, Osumi. Types No. 94,716 A. N. S. P., from No. 

 1,447 of Mr. Hirase's collection. 



Compared with S. japoniciim (A. Ad.), this form differs in the more 

 descending last w^horl, the deeper umbihcus and more excised or 

 receding columellar lip. The aperture is longer than wide in yakii- 

 shimanum, nearly round in japonicum. It is perhaps more closeh'' 

 related to *S. nakadai of Tanega-shima, a smaller shell with an oper- 

 culum of fewer whorls, but having an aperture much as in S. yaku- 

 shimanum. 

 Diplommatina gotoensis n. sp. 



Closely related to D. cassa, but with longer conical spire, rapidly 

 tapering and conic above the penultimate whorl, which is the largest ; 



