1900.] NATURAL SCIENCES OF rHILADELIMI I A. 681 



lateral position. Palatal plicje lateral, the upper rather long and 

 curved down at its outer end, lower plica shorter but well devel- 

 oped, two small, short, contiguous plicai (or sometimes one plica) 

 midway between them. Clausilium rather long, with parallel 

 sides and thin rounded apex ; posterior end tapering (PL XXV, 

 fig. 41). 



Length 12.2, diam. 2.5 mm. 



Length 10.5, diam. 2.5 mm. 



Ushirohawa, Tosa, Shikoku Island (Mr. Y. Hirase). This 

 little species differs notably from the allied C. caryostoma and 

 C. gradlispira in the produced last whorl, the aperture standing 

 out somewhat like that of a Diaphora or Urocoptis, though only 

 shortly. The spire is more attenuated than in those species. It 

 is very solid and strong for so small a Clausilia. The specimens 

 vary a good deal in size. Types are No. 79,320 coll. Acad. Nat. 

 Sciences, from No. 550 of Mr. Hirase' s register. 



(Group of C. aurantiaca.*) 

 Clausilia shikokuensis n. sp. PI. XXV. figs. 30, 31, 32. 



Shell rimate, fusiform, somewhat inflated, attenuated and with 

 concave outlines above; solid; of a rather bright orange-brown 

 color; finely, rather obsoletely striated, the last whorl more 

 strongly and sharply so. Whorls about 10J, moderately convex, 

 separated by impressed sutures, the last whorl compressed laterally, 

 shortly solute. Aperture ovate, somewhat oblique, the sinulus 

 rather high and retracted ; peristome orange-brown, reflexed and 

 thickened, continuous, slightly emarginate above. Superior 

 lamella somewhat oblique, rather strong, continuous with the spiral 

 lamella. Inferior lamella scarcely emerging, inconspicuous in 

 the front view, but becoming strong and thickened within; viewed 

 obliquely from below it is seen to be distinctly bifurcate. Sub- 

 columellar lamella not emerging, invisible from in front, but seen 

 in an oblique view. Principal plica visible within the mouth, 

 extending inward a little beyond the lunella. Lunella lateral, 

 well curved, especially above, where it is continued backward in 

 and quite united with the anterior end of a short upper palatal 

 fold, being thus somewhat irregularly bow-shaped. Clausilium 

 narrow, tongue-like. 



Alt. 16, diam. 3.8, longest axis of aperture 3.5 mm. 



