Fossils from the Upper Musashino of Kazusa and Shimosa. 75 



grains which are round, close, more or less contiguous either direct- 

 ly or by a short prolongation sent off from their lateral sides. These 

 grains are also linked vertically by a short, somewliat oblique riblet. 

 On the last part of the body-whorl there is an interstitial spiral 

 thread also granose at the extreme end (near the aperture). Aper- 

 ture squarely rhombic. Canal bent sideward and also backward. 

 FossiJ occurrence. — Shito. 



Family Trichotropidae. 



Genus TRICHOTKOPIS, Broderip et Sowerby. 



95. Ti'iehofropis titiiearinafn, Broderip et Sowerby. 



PI. xiir. Fig. 11. 



Trichotropis iinicariitata. Sowerby, Thes. Conch , III, p. 323, pi. 285, fig. 10. Danker, 

 Index Moll., p. 105, pi. I, figs. 11, 12. Tryon, Man. Conch., IX, p. 44, pi. 7, fig. 

 56. Pilsbry, Cat., p. 59. Toknnaga, Foss. Env. Tokyo, p. '20, pi. I, tig. 38. 



Trichotropis coronata. Bmnns, Geo!. Env. Tokio, p. 34 (not T. coronata Gould). 



This is a very characteristic shell easily recognized by its 

 tabularly shouldered whorls with an elevated and crenulate keel 

 on the shoulder, a large umbilicus surrounded by a sharp and 

 elevated margin, ovate aperture and a very short straight canal. 

 The sculpture is almost absent save some faint spiral striae or 

 threads sometimes visible on the body-whorl below the shoulder. 



Fossil occurrence. — Shito (frequent). Oji and Shinagawa in 

 Musashi. 



Living. — Northern to Western Japan. 



Family Vermetidae. 



Genus THYI.At;oi>ES, (liittard. 



«i<». Thylat'odes inetlusae, Pilsbry. 



PI. ni. Fi^-. 17. 



Tlii/lacodes medusae. Pilsbry, Proc. Acad. Nat. Sei. Phil., 1891, p. 471, pis. 17, 18. 

 Catalogue, p. 59, pis IV, V. Yokoyama, Foss. Minra Penin., p. 71, pi. IV, fig. 7. 



Only a single fragment. 



Fossil occurrence. — Otake. Lowei" Musashino of Mi3-ata and 

 Yokosuka. 



