742 PROCEEDINGS OF THE ACADEMY OF [Oct.,. 



periphery; thill, amber-tinted, somewhat transparent and brilliantly 

 glossy below, opaque above, with the luster of a dull silk, the opaque 

 appearance resulting from a sculpture of excessively fine and close ver- 

 tical or radial striae which extends over the periphery and forms a band 

 at the circumference of the base around the glossy basal area, which un- 

 der a strong lens shows fine, well-spaced spiral lines. Whorls 4, convex, 

 the suture well impressed. Aperture lunate, the columellar margin 

 not perceptibly thickened, triangularly reflex ed at the insertion. 



Alt. 1.9, diam. 2.7 mm. 



Giiran, Taiwan. Types No. 89.869 A. N. S. Phila., from No. 1,368 

 of Mr. Hirase's collection. 



The dull silky surface is like that of some species of Euconulus, 

 Guppya, etc. Only four specimens were taken. The non-callous 

 columella may cause the removal of this species from Microcystina, yet 

 the number of whorls is so small that we would hardly consider it a 

 Kaliella. There are traces of spiral sculpture on the first whorl. 



Microcystina lissobasis n. sp. 



Shell minutely perforate, depressed, with low-conoid spire and con- 

 vex base; thin and fragile, pale yellow, subtransparent. Upper sur- 

 face and a zone at and below the periphery having a silky luster, the 

 rest of the base smooth and glossy. "Wlioiis 4, convex, separated b}' 

 an impressed suture, the periphery rounded. Aperture wideh' lunate, 

 columella oblique, slightly thickened within, its edge a little dilated. 



Alt. 1, diam. 2.1 mm. 



Hotawa, Taiwan. Types No. 89.870 A. N. S. Phila., from No. 1,423 

 of Mr. Hirase's collection. 



This species is related to M. lamprobasis, having the same silky upper 

 surface and glossy base. It differs by its smaller size and much wider 

 aperture. About 20 specimens^were taken. 

 Microcystina radiata n. sp. 



Shell minutely perforate, depressed, thin, yellowish-corneous, sub- 

 transparent, very glossy. Sculpture of fine, close and minute radial 

 strife and grooves above, the base smooth. Spire low-conoid, the apex 

 obtuse. Whorls 4^, moderately convex, slowl}" increasing, the last 

 much wider, rounded peripheral!}-, convex below. Aperture lunate; 

 columella dilated above, slighth" thickened within. 



Alt. 1.7, diam. 2.5 mm. 



Giiran, Taiwan. Types No. 90,224 A. N. S. Phila., from No. 1,371 

 of Mr. Hirase's collection. 



Related to M. sinapidumi, but unlike it in scul])ture. Onl}' four 

 specimens taken. 



