816 PROCEEDINGS OF THE ACADEMY OF [Dec., 



I formerly included the species of this section in Hemiphcedusa, from 

 which they differ totally in the form of the clausilium, and in the spir- 

 ally ascending inferior lamella. C. excellens, of which the clausilium 

 and palatal armature are unknown, will probably be found to belong 

 to Luchuphcedusa. The other species are closely related. 



Clausilia okinoerabuensis n. sp. PI. LIT, figs. 13, 14. 



Shell subcylindric below, the upper half tapering and somewhat 

 attenuate; pale uniform yellowish-corneous. Surface glossy, finely, 

 strongly striate, the striation coarser on the back of the last whorl. 

 Whorls 10, the upper 3 smooth. Aperture ovate-piriform, the peris- 

 tome reflexed and thickened, with a small notch on the right side of 

 the superior lamella, and very indistinct traces of crenulation near it. 

 Superior lamella marginal, small, subvertical, continuous with the 

 spiral lamella which penetrates to the left side. Inferior lamella form- 

 ing a rather prominent fold in the aperture, calloused and spirally 

 ascending within, shorter than the spiral lamella. Subcolumellar 

 lamella emerging to the lip-edge. Principal plica short, dorsal and 

 lateral. Lunella strong, oblique, arising from the middle of a strong 

 lower palatal plica, and bending inward above in a rather long upper 

 palatal plica. 



Length 22 to 23, diam. 5 mm. 



Clausilium (PI. LIII, figs. 23, 24) well curved, the columellar margin 

 straight, slightly excised at the filament, the palatal margin very con- 

 vex, then tapering and concave toward the apex, which is blunt and 

 thickened. 



Okinoerabushima, Osumi. Types No. 87,611, A. N. S. P., from No. 

 1,251 of Mr. Hirase's collection. 



A smaller species than C. crenilabium, with the upper palatal plica 

 better developed, with scarcely any interlamellar plication of the upper 

 lip, and a callous but not internally double inferior lamella. The 

 clausilium is less deeply channeled distally. It is not so coarsely 

 sculptured as C. bernardii, and is more slender than C. ptychochila. 



Fossil specimens from a deposit of calcareous sand on the shore of 

 Okinoerabushima are similar to the living specimens in structure, but 

 some specimens are shorter: 



Length 23.6, diam. 5 mm. 



Length 21, diam. 5.4 mm. 



Section LUCHUPH^DUSA Pils. 

 Clausilia azumai n. sp. PI. LII, figs. 6, 7. 



Shell solid and strong, cylindric below, the upper half regularly taper- 



