Fossils fri rn the Upper Musashino of Kazusa and Shimosa. 113 



3) living in North ein to Western Japan that it can not be considered 

 as more than a variety. The chief difference of tlie fossil is in 

 the angulation of the whorls being sharp and distinct, while it is 

 less sharp or even indistinct in the living form. Besides, the fossil 

 shows on its base spiral threads instead of distant spiral grooves. 



Fossil occurrence. — Otake (frequent), Shisui, Tega, Shito 

 (frequent). Shinagawa (rare). 



Genus BASILISSA, Watson. 



167. Hasiliss€i ? Iterittscula, Yokoyaiaa. 

 PI. V. Fig. 24. 



Shell thin, turbinate-conic W^hoiis about six of which the first 

 two are nuclear and rounded. Post-nuclear whorls convex, with 

 two faint angulations dividing the surface into three nearly equal 

 parts. Each angulation marked b}^ a fine spiral stria. Surface 

 between angulations very finely spirally striate, the striae being 

 visible only with a magnifier. Periphery sharply angulate and 

 somewhat projecting above the general surface of the body-whorl. 

 Base convex with very fine spiral lines. Umbilicus provided with 

 a chink. Aperture irregularly and roundly four-sided. Outer lip 

 very thin. Height 8 millim. Diameter 7 millim. 



A single specimen. The nuclear whorls are coloured dark 

 brown, while the remaining part is dirty light green. These colours 

 may be the remains of some original coloration. 



Fossil occurrence. — Shito. 



Genus U.'?lBf>XIUW, Link. 



16S. Uinboitiuin f/iyanteunt, (L/esson). 



Umbonium gifjanteurn. Pilsbry in Tryon's Man. Conch., XI, p. 454, pi. 58, figs. 17-19. 



Catalogue, p. 100. Dunker, Ind. Moll., p. 134. Yokoyama, Foss. Miura Penin.,. 



p. 94, pi., VI, fig. 5. 

 Txotella gigantea. Lesson, lUustr. cle Zool., tome 17, 1831. Kiener, Spec, et Icon. 



Coq. Viv., p. 16, PI. 3, fig. 7. Sowerby, Thes. Conch., V, p. 136, pi. 472, figs. 



15, 16. 

 Globulus giganteus. Lischke, Jap. Meeresconch., Ill, p. 63. 



