1907.] NATURAL SCIENCES OF PlIILADKLPIIIA. 505 



that (Icscrilx'd by Scluiiackt'r mikI Boci t.<;(M- hy its broadly interrupted 

 upper palatrU plica and the iioii-ascciidiuj:; last whorl. 



Clausilia oxypomatica ". ^-i)- I'l. XXXIII, fi^s. 20 24. 



Shell cylindric-fusiforin, attenuated towards the rather acute apex, 

 pale chestnut or brownish corneous, slightly transparent, the old shells 

 opaque, very finely but not deeply striate, more coarsely so on the 

 last half whorl. Whorls 9 to 10^, but slightly convex, the last com- 

 pressetl laterally, the base tapering. Aperture rhombic-ovate. Peris- 

 tome expanded and reflexed, rather narrow and not much thickened 

 except in old shells; parietal wall free, emarginate above the superior 

 lamella. The superior lamella is vertical, marginal, thin but rather 

 high, continuous with the spiral lamella, which is very high in the 

 lateral position, and penetrates to a point above the superior lamella. 

 The inferior lamella recedes deeply, is straight and oblique within the 

 last w'horl, and penetrates inward less deeply than the spiral lamella. 

 The subcolumellar lamella emerges. Principal plica more than a half 

 whorl long, dorsal and lateral, approaching the aperture. Upper 

 palatal plica thin but moderately long, with the lunella forming a 

 T-shaped barrier. 



Length 13, diam. 2.7 nmi. 

 " 11, " 2.7 " 



The clausilium (PI. XXXIII, figs. 21, 22, 23) is not much curved, but 

 is quite concave internally and convex or somewhat baggy externally. 

 The columellar side is very deeply excised at the filament. The two 

 sides are about equally arcuate, the apex somew^hat acuminate and 

 projecting, as though a drop were hanging there. There is a rib inside 

 along the columellar margin, and a more diffuse callus on the outside 

 along the palatal margin. 



Oshima, Osumi. Types No. 89,889, A. N. S. P., from No. 1,336 of 

 Mr. Hirase's collection. 



This species falls into the second division (II) of my key to Ilemi- 

 zaptyx {Proc. A. N. S. Phila., 1904, p. 825). It differs from both the 

 species of that division (C. hijpcraptyx and C. yyiuniis) in having the 

 upper palatal plica somewhat longer, the lunella joining it in the 

 middle. It is thinner and more slender than C. muniis, larger, wider, 

 paler and less sharply striate than C. In/pcraptyx {oxypomalicus, having 

 a sharp li<l or "clausilium"). 



At Koniya, Oshima, there is a variety of C. munus more delicate 

 than the type lot, the shell usually somewhat smaller and more slender. 

 It is this i'oi-ni which approaches C. oxypomatica. 



