Fossils from the 'Jinn Peninsula and its [mmediate North. 35 



This species is quite like Turbo granulatus < i-melin" in form and 

 sculpture, with the only difference of being not umbilicated. On 

 this account, it is often considered as only a variety of the latter. 



Four specimens have been collected and also two opercula 

 probably belonging to the same species. These opercula are 

 calcareous, round in outline, convex and granular. 



Fossil occurrence. — Yokosuka Zone (Yokosuka and ( >tsu). 



Living. — Central and Western Japan; Corea. 



Tokunaga mentions Turbo granulatus Gm. among the fossils of 

 Tabata, giving Turbo coreensis as its synonym, but nothing is said 

 as to whether the specimens belong to the true granulatus or to 

 var. coreensis. 



Genus Leptothyra, Carpenter. 



92. Leptothyra amussitata, (Gould). 



Pl. V. Fig. 21. 



Leptothyra amussitata. Tryon, Man. Conch., X, p. 250, pl. 55, figs. 11, 72. Pilsbry, Cat. 

 Mar. Moll. Japan, p. 90. 



rrochua amussitatu*. Tokunaga, Foss. Env. Tokyo, p. 29, pl. II, fig. 2. 

 Turbo amuesitatus. Gottlt?, < >tia Concnblogica, p. 160. 



Tiiyox gives the description of this species as follows: — 

 *" Shell globose-conic, imperforate, solid, uniform dee}) 

 crimson; sutures deeply impressed; whorls 5, convex, spirally 

 Urate, the lira? large and prominent on middle portion of whorl, 

 alternating with smaller intercalated riblets; base very finely 

 concentrically striate, the whole surface decussated by numerous 

 regular oblique impressed lines in the direction of incremental 

 striae; last whorl descending anteriorly; aperture subcircular, 

 oblique, less than half the length of shell, silvery within; 

 columella slightly tuhercuiate at base. Alt. 8-10, diam. 8-10 

 millim. ' ' 



Many specimens have been collected in the Yokosuka Zone. 

 Nearly all of them retain more or less the original colour. The 

 intercalated riblets are not always observable, though distinct in 

 some. A specimen from Koshiba which is bleached is the largest, 

 measuring millim. in height and diameter. 



