]^ßß ■ Art. 1. — M. Yokoyama : 



measures 32 inillim. in length, 33.5 millim. in height and 10.5 

 miUim. in depth. 



This shell is closely allied to Corbicula sandai Reinhardt 

 (Kohelt, Fauna Moll. Extramar. Jap., p. 153, pi. 2U, fig. 3) from 

 which it differs by the presence of a posterior carina. 



Fossil occurrence. — Otake, Kamenari, Shito (common). 



Living. — Central Japan (coast of Kazusa). 



26S. dm'hicula L'obelfi, Yokoyama. 

 PI. XIII. Figs. 18, 19. 



Three left valves. The shell is decidedly longer (lower) than 

 the preceding with l)eaks smaller and less swollen. The outline is 

 ovato-trigonal, more or less rounded in front and truncate be- 

 hind. The angle at which the antero- and postero-dorsal margins 

 would meet, when produced, is somewhat greater than a right 

 angle. Convexity of shell moderate. Surface with rude lines of 

 growth which make it unequally grooved. 



The measurements of the three valves are as follows: 



Length. Height. Depth. 



29.4 millim. (10) 27.0 rniHim. (9.0) 8.8 miUim (2.9) 



22.8 „ (10) 20.5 „ (8.9) 7.1 „ (3.1) 



13.1 „ (10) 11.8 „ (9.0) 3.7 „ (2.9) 



The nearest ally of this species seems to be Corbicula pexata 

 Prime (Kobelt, loc. cit., p. 157, pi. 20, fig. 2) in which, however, 

 the beaks are more tumid. 



Fossil occurrence. — Shito, Otake. 



Living. — Central Japan. 



Family Pleurophoridae. 



Genus C0RAI.I.10PHAGA, Blainville. 



309. Coralliophaga vnvullioitUaya, (Cheuniitz). 



PL XIV. Fig. 5. 



GomUioj)haga coralUophaga. Pilsbry, Cat., p. 136. H. and A. Adams, Genera of 



Recent Mollusca, II, p. 439, pi. 109, figs. 6, 6a. 

 Goralliophaga litho])hagella. Dunker, Ind. Moll, p. 209. 



