622 PROCEEDINGS OF THE ACADEMY OF [Sept., 



sometimes whitish. Sculpture of very fine, low and delicate vertical 

 striae, obsolete on the front of the last whorl, and often largely lost by 

 wear. AYhorls 6^, convex, the constriction at the beginning of the last 

 whorl, above the insertion of the outer lip; last whorl rounded below. 

 Aperture vertical, subcircular, the peristome reflexcd, thickened within, 

 continuous in a delicate callous with raised edge across the parietal 

 wall; somcAvhat angular at the junction of the columellar and basal 

 margins. Columellar lamella strong at the mouth and opposite the 

 palatal plica. Palatal plica strong and long, its inner end only under 

 the parietal callous. Spiral lamella long but rather low. 



Alt. 2.7, diam. 1.5 mm. 



Kagoshima, Satsuma. Types No. 81,896, A. N. S. P., from No. 702 

 of ]\lr. Hirase's collection. It has been sent also from Kami-Koshi- 

 kijima, Satsuma; Watarimura, Kij^oragi and Fukuregi in Higo; Sa- 

 ganoseki, Bungo; and Obi, Huga. 



We formerly considered these forms to belong to D. cassa; but 

 further study has shown them to be shorter and less cylindric than 

 cassa, with a more ventrally situated and more distinct constriction. 

 D. cassa has not yet been found in Kj^ushu, and D. ky^isJmeyisis has 

 not occurred in Hondo or Shikoku. The form from Kami-Ivoshiki- 

 jima, Satsuma, is slightly smaller and more slender. Most species of 

 these islets show more or less modification. 

 Diplommatina tokunoshimana n. sp. 



Shell conic above, cylindric below, dull reddish, rather closely, finely 

 and delicately striate. Whorls 6^, moderately convex, the last rounded 

 beloAv, strongly ascending in front. Constriction slight, just in front 

 of the upper insertion of the peristome. Aperture circular, with a 

 notch at the base of the columella, the peristome thick, thickened out- 

 side. Columella straight. Columellar tooth strong. Parietal cal- 

 lous large, approaching the sviture above. Palatal plica moderately 

 long, situated under the parietal callous. 



Length 3.3, diam. 2 mm. 



Tokunoshima, Osumi. Types No. 87,649, A. N. S. P. , from No. 1 ,217 

 of Mr. Hirase's collection. 



Very peculiar by the spout-like base of the aperture, unlike any 

 other species of Japan or the Riukiu Islands. 

 Diplommatina ventriosa n. sp. 



Shell obese-fusiform, the penultimate whorl large and swollen, the 

 spire conic, last whorl smaller; dull reddish-brown; evenly, closely 

 and almost obsoletely striate. Whorls 6^, very convex, the last well 

 rounded. Constriction slight, situated in front of the insertion of the 



