Fossils from the Miura Peninsula and its Immediate North. (»f, 



periphery and slightly convex smooth base, is evidently a species 

 now living near the coast of Central and Western Japan. 



Fossil occurrence. — Naganuma. 



Living. — Central and Western Japan. 



108. Umbonium costatum, (Valenciennes). 

 Pl. VI. Fig. 6. 



Umbonium costatum. Pilsbkt in Teton's Man. Conch., XI, p. 454, pl. 59, tigs. 34, 35. 

 Dünker, Index Moll., p. 134. 



Botella cos'ata. Valenciennes in Kienek, Spec, et Icon. Coq. Viv., p. 10, pt. 2, fig. 2. 



Globulus lostatus. Lischke, Jap. Meeresconch., I, p. 91. Schrenck, Moll. d. Ainurl. a. d. 

 nordjap. Meeres, p. 367. 



A large specimen measuring about '20 millirn. in diameter 

 and a much smaller one. 



This species is like the preceding in shape, but easily dis- 

 tinguished by spiral grooves running over the whorls and a 

 tendency to tuberculation of the uppermost part of the same. 

 The original colour is faintly preserved. 



Fossil occurrence. — Naganuma Zone (Naganuma). Upper 

 Musashino of Shimosa and Ka^usa. 



Living. — Northern, Central and Western Japan. 



Family Cycloslrematidae. 



Genus Ct/v/ostrettut, Marryatt. 



109. Cyclostrema duplicatum, Lischke. 



Pl. VI. Fig. 8. 



Cycloftrma dupli:utum. Lischke, Malakozool. Blatter, vol. 19, p. 101. Jap. Meereseoi 

 vol. m, p. 61, pl. Ill, figs. 9, 10. 



A single example 4 millim. in diameter agrees fairly well 

 with a species described by Lischke under the above name. It is 

 characterized by the double-keeled periphery above which there 

 are two more keels. The base was described by Liscuke as 

 having two keels and the elevation surrounding the umbilicus is 

 said to be keel-like. But in our specimen the base shows only a 

 single keel and instead of a keel-like elevation there is only a, 

 rounded swell. The round and thickened mouth and spiral striae 



