173 269 



shell and curve over towards the front. In the right valve there is one cardinal 

 tooth, which fits into a corresponding pit in the left valve, behind which is a stout 

 process or denticle supporting the ligament. The interior of the valves, like the 

 exterior, is clear-white in colour. 



Long. 95 mm., alt. 5 mm., crass. 55 mm. 



Between Koh Kut and Koh Kahdat, 10 fathoms, shells (^/a). Koh Kahdat ("a). 

 South of Koh Kahdat, 8—10 fathoms, mud (^/a). 



This small characteristic species, which in form recalls an /Irca (ßarfca/ia), stands 

 nearest Corbula tenuis. Sow., from which it differs, however, in many points. The 

 specimens which I have before me are not well-preserved, no trace of epidermis 

 is seen upon any of them ; also, I cannot, unfortunately, state anj'thing about the 

 reciprocal size of the two valves. But in all probability, the difference in size is 

 not very great, as both right and left valves are at hand, but of different individuals. 



Corbula rugifera, A. Ad. (Smith). 



Corbula rugifera, A. Adams, MS. in Coll. Cuming. Brit. Mus. 



— — — Edg. Smith, Proc. Malacolog. Soc. London, V, isms, p. 399, No. 373, pi. 15, figs. 



9—10. 



— — H.Adams, Melvill and Standen, Proc. Zool. Soc. London, 1906, p. 843. 



Koh Kram, 20 fathoms (-/a). 



Long. 35 — 8 mm. 



Distribution: — Singapore (Sv. Gad, Zoolog. Mus. Copenhagen). Karachi 

 (Hindustan, Melvill). Umkomaas (South Africa, Burnup). 



After Edg. Smith in 1903 had published the description of the present charac- 

 teristic species from South Africa, Melvill, in 1906, recorded that it had been 

 taken at Karachi. Its occurrence at Singapore and in the Gulf of Siam, renders 

 it probable that later on it may also be found in the interjacent waters. 



Corbula Taheitensis, Lam. 



Corbula taïtensis, Lamarck, Hist. nat. d. anim. s. vert., V, 1818, p. 496, No. 5. 



— Taïtensis, — — — — éd. 2, VI, p. 139, No. 5. 



— Taheitensis, — Reeve, Conchol. icon., 11, Corbula, Sp. 15. 



— Taliitensis, — Hanley, Catal. of rec. biv. shells, p. 46, pi. 12, fig. 30. 



— Taitensis, — Hidalgo, Fauna malacol. de 1. isl. Filip., II, 1903, p. 31, No. 59. 



Koh Chuen, 30 fathoms ('/a). Between Koh Mesan and Koh Chuen, 25—38 

 fathoms, stones and shells (1 -|- ^/a). North end of Koh Chang, 12 fathoms, old 

 coral blocks ('/a). 



Long. 6—8 mm. 



Distribution— Aden. — Philippines, New Guinea, Torres Str., Tahiti, 

 Funafuti Atoll (Hedley). 



