r)o4 PROCEEDINGS OF THE ACADEMY OF [Dcc. , 



known from so far north or northeast. It is more attenuated 

 above, and the peristome is notched on the left side of the terra i- 

 aiation or the superior lamella. 



Group of C taiief/ashimce. 



Solid and strong Tyrannophcediisw with the clausilium oblique 

 and thickened distally, the superior lamella separated from the 

 spiral lamella, which penetrates past the ventral side, accompanied 

 by the inferior lamella; lunella subventral; subcolumellar lamella 

 strongly emerging. There is a strong ridge or crest behind the 

 outer lip, parallel with it. 



Similar to the group of C. bilabnda in internal structure, but 

 differing in the crest behind the lij). Species are known from the 

 northeastern grou{) of Riukiu Islands, and from southern Kiushiu. 

 Species two: C. oxycyma, with a distinct upper palatal plica devel- 

 oped, length 14 mm., and C. tanegashinuc, which has the upper 

 palatal plica represented only by an inward bend of the upper end 

 of the lunella, length 16-18^ mir. 



Clausilia oxycyma n. sp. P). XXXVII, ligs. 35, 36, :',7, M^. 



Shell rim ate, fusiform, rather slender, attenuated above, glossy, 

 rather dark red-brown when unworn ; finely striate, a little more 

 coarsely so pn the last whorl. Whorls 9!^ to nearly 11, moderately 

 convex, the last three whorls of almost equal diameter, last whorl 

 compressed laterally, tapering, rising into a strong, rather acute 

 ridge or crest a short distance behind the lip and parallel with it. 

 Aperture piriform, slightly oblique, brown within; peristome nar- 

 rowly reflexed, continuous, white, scarcely emarginate at the posi- 

 tion of the superior lamella. Superior lamella small, marginal, 

 slightly oblique, not continuous u^ifh the spiral lamella. Spiral 

 lamella very high within, of equal length with the inferior lamella, 

 both continuing past a ventral position. Inferior lamella very 

 deeply receding, twisted within. Subcolumellar lamella emerging 

 to the lip-edge, bounded by grooves. Principal plica strong, 

 reaching from the dorsal to the ventral side. Lunella latere- ven- 

 tral, oblique, joining the middle of strong, rather long, oblique, 

 upper and lower palatal plicse. 



Length 14, diam. 3 to 3^ mm. 



Clausilium (PI. XXXVII, figs. 41, 42) moderately curved, the 



