416 PROCEEDINGS OF THE ACADEMY OF [Julv, 



The clausilium (PI. XXII, figs. 12, 13, 14) is strongly curved 

 below, and becomes very thick toward the apex. The distal end 

 has two apices separated by a notch, the outer one conic and 

 rather broad, the inner blunt and bent nearly at a right angle with 

 the body of the plate. 



Xase, Oshima (Mr. Y. Hirase, No. 653a). 



This exceedingly peculiar species has the crenulate right lip of 

 most of its group, but it differs from all known species except the 

 next in the great development of the posterior bay or " sinulus " 

 of the aperture. It is difficult to gain a correct conception of the 

 closing apparatus, so contracted is the cavity of the last whorl 

 by the enormously developed lamellse and plicre. The deeply 

 immersed subcolumellar lamella is a prominent feature, differentiating 

 C. oshimce from C. j^seudoshimce ; but as I have remarked above, 

 this is masked by the sulcation of the lip, by which rounded 

 lamellae are produced in the subcolumellar position. 



Clausilia pseudoshimae n. sp. PI. XXII, titrs. 7, S, 9, 10. 



Shell very similar externally to C. oshimce; a little smaller; 

 aperture and lip the same, except that the subcolumellar lamella 

 emerges to the Ui)-edrje. Internal structure the same, except that 

 the spiral trend of the inferior lamella, as seen from the back in 

 an opened shell, is made irregular by two prominent angles; there is 

 a rather long, latero-dorsal, uj^per palatal plica opposite the great 

 lateral dilation of the inferior lamella. The very long lower 

 palatal plica gives off a very short and extremely oblique lunella 

 in a ventral position, where the clausilium lodges. The clausilium 

 (PI. XXII, fig. 11) has two subequal blunt apical points, sepa- 

 rated by a rather wide notch. 



Length 19.3, diam. 4, longest axis of aperture 5 mm. 



Length 17, diam. 4, longest axis of aperture 4.7 mm. 



Furuniya, Oshima (Mr. Y. Hirase, No. 6536). 



Strikingly like C. oshimce in general aspect, yet readily distin- 

 guishable by a number of important interna) characters. On 

 cutting the shell it is found to be decidedly less strong than in the 

 other species. The clausilium lodges in a ventral position. The 

 form of the basal lip is poorly represented in fig. 8. The other 

 fiirures show it correctlv. 



