1901.] :^fATURAL sciences of PHILADELPHIA. 423 



Clausilia niunus n. sp. PL XXIII, liss. 34. 35. 36. 



Shell rather small, fusiform, slender and much attenuated above, 

 rather obese below; brown and glossy when unworn, but often 

 lustreless and more or less eroded. Finely and closely striate, the 

 later half of the last whorl much more coarsely so. Whorls 9 

 to 9^, rather convex, the penultimate whorl widest, the last whorl 

 contracted, tapering. Aperture rhombic-ovate, the peristome 

 whitish, reflexed, moderately thick, slightly emarginate at the 

 position of the superior lamella. Superior lamella vertical, reach- 

 ing the margin, continuous with the spiral lamella. Inferior 

 lamella immersed, receding, not visible in a front view, but seen 

 by looking obliquely into the aperture; almost straightly ascend- 

 ing inside. Subcolumellar lamella emerging to the lip-edge, with 

 a groove on each side. Principal plica nearly a half whorl long, 

 its end visible within the throat from the aperture, extending 

 inward slightly beyond the closing apparatus. Upper palatal 

 plica short, converging a little inwardly toward the principal plica; 

 not connected with the arcuate, obhque, rather strong lunella, the 

 lower end of which curves inward somewhat. 



Length 15, diara. 3.5 mm. 



Length 13.5, diam. 3.6 mm. 



Length 13, diam. 3 mm. 



Clausilium rather broad and short, tapering to a mucronate apex, 

 heavily thickened on the columellar side at and near the apex, 

 nearly straight, curved only near the filament, where it is abruptly 

 narrowed, and deeply excavated or emarginate on the columellar side. 



Oshima (Mr. Y. Hirase, No 646). 



In general form this species resembles G. brevior and C. axca- 

 jiensis. It differs from the latter in the wider peristome, in having 

 the lunella free from the upper palatal plica, and in the shape of 

 the clausilium, which in this species resembles that of TijrannophcB- 

 diisa, it being shorter and broader than in Hemiphcedusa, and 

 strongly thickened toward the apex, along xhe columellar side. 



Section ZAPTYX Pilsbry. 



Vide these Proceedings for 1900, pp. 446, 672. 

 Clausilia hyperoptyx Piisbrj-. 



This species was sent by Mr. Hirase as from " Loo Choo " — 

 that is, I suppose. Great Loo Choo (Luchu), Nawa, or Okinawa 

 Island. A further lot, No. 4576, has been sent from Yayeyama. 



