1904.] NATURAL SCIENCES OF PHILADELPHIA. 821 



One specimen sent with the type lot is smaller, length 11.7, diam. 4 

 mm., with 6 whorls, pale yellowish in color, and the inferior lamella 

 proper, while visible in the throat, does not extend to the lip (PI. LIT, 

 fig. 3). 



Rection STEREOPH.EDUSA Bttg. 

 Clausilia subMckonis n. sp. PI. LIV, figs. 34, 35, 36, 37, 38. 



^Shell fusiform, attenuate above, but terminating in a rather large 

 apex, solid, light yellow, rather strongly rib-striate. Whorls 12 to 12^, 

 convex, the first 3 or 4 cylindric, the penultimate whorl swollen as seen 

 dorsally, last whorl flattened, convex below, not noticeably different 

 in sculpture. Aperture ovate, subvertical, the peristome white, 

 roflexed and thickened within, continuous in a slightly raised ledge 

 across the parietal wall, a little sinuous or notched at the position of the 

 superior lamella. Superior lamella decidedly oblique, marginal, con- 

 tinuous within with the spiral lamella, which penetrates inward to the 

 middle of the ventral side. Inferior lamella appearing in front as a 

 strong, subhorizontal fold crossing a much more oblique callous colu- 

 mcllar fold wdiich continues weakly upon the lip; the whole appearing 

 as two nodules. Within the back the inferior lamella is strongly 

 spiral but not very high. It penetrates inward more deeply than the 

 supeiior lamella. The subcolumellar lamella emerges to the lip-edge. 

 The principal plica is very short and lateral. Palatal plicae 4, strong, 

 somewhat oblique and parallel, the lower one a little arcuate, the two 

 intermediate plicae shorter than the others. 



Length 21 to 22.5, diam. 5 mm. 



The clausilium (PI. LIV, figs. 34, 35) is narrower than usual in 

 Stereophcedusa; the columellar margin is straight, a little excised near 

 the filament; the palatal margin convex, contracting distally; the 

 distal end is compressed and ridged inside, and the apex is rounded 

 and noticeably thickened. 



Isobe, Shima. Types No. 86,499, A. N. S. P., from No. 1,168 of 

 Mr. Hirase's collection. 



This Stereophceclusa is related to CI. hickonis Kobelt, but hickonis is 

 more attenuate above, has more whorls, which are less convex, finer 

 sculpture, longer upper and lower palatal plicse, the latter more curved, 

 and the superior lamella in C. hickonis is visually separated from the 

 spiral lamella, or at least much lower at their junction. 



C. suhhickonis has been taken also at Gokasho-mura, Ise, a place not 

 very far from the type locality. The columella is not quite so con- 

 spicuously binodose in these specimens, two of which measure — 



