Fossils fr.)m the Upper Musashino of Kaziisa and Shimosa. 23 



2. Solitlula clathrata^ Yokoyama. 

 PI. I. Fig. 2. 



Shell moderate in size, solid, ovately oblong. Whorls about 

 seven, somewhat convex. Spire short and pointed, the body-whorl 

 occupying about four-fifths the height of the shell. The sculpture 

 consists of spiral sulci which number usually five on the upper 

 whorls and twenty or more on the body-whorl. These sulci which 

 are almost ahvays narrower than the flat interspaces are finely 

 latticed by raised lines of growth which, though prominent on the 

 front-side of the body-whorl, are either indistinct or obsolete on its 

 back-side and also on the upper whorls. Aperture long, equalling 

 to almost tw^o-thirds the height of the shell, widened and rounded 

 in front, narrowed and acuminate behind. Columella-folds two ; 

 the upper weak and not prominent, the lower strong and bilobed, 

 the lower lobe l)eing weaker than the upper. Sutures subchannel- 

 ed. Height ]'.). 3 millim. Diameter 9.5 millim. Height of body- 

 wliorl 1(3 millim. Length of aperture 13 miUim. 



This species is closely related to the preceding, but it grows 

 larger, and the sulci are latticed and not punctured. Also the 

 aperture is not so produced, and the two lobes of the lower 

 columella-fold ai'e unequal in size. 



Fossil occurrence : — Shito (only three specimens). 



Genus tEL'COÏINA, A. Adams. 



r$. I^ettcotinti ffigatitea. (Duiikt'r). 



PI. I. Pig. 3. 



Leucotina (fiyantea. Pilsbry, Cat. Mar. Moll. Jap., p. 7. Tryon, Man. Conch., vol. XV, 



p. 167, pi. XVIII, figs. 92, 93. 

 Act.eon i/iffanteus. Danker, Index Moll. Mar. .Jap., p. 160, pi. II, tig. 59. 

 Tornatella gUjantea. Toianiaga, Foss. Env. Tokyo, p. ol, pi. II, tig. 10. 



Many specimens. The largest measures 29 millim. in height 

 and 13 millim. in diameter. The whorls number eight with flat 

 spiral ribs on them, ten on the penultimate and twenty two on the 

 ultimate whorl. Under a lens the interspaces appear cross-striated, 



