252 156 
circular, convex, white, rather thin; umbones high and situated at the middle of 
the axis of the shell. Apex turning towards the anterior end. The whole surface 
covered with a network of close-set, fine, parallel lines, which cross each other; 
they proceed from the umbones and from the upper sides and radiate outwards 
towards both ends and towards the ventral side. Upon each valve there is a large, 
elongated, crescent-formed lunule, circumscribed by a groove; it is glossy, destitute 
of network sculpture, and striped only by the lines of growth; the brown ligament 
is external. The interior of the valves is glossy, milky white; in the right valve 
there are two diverging cardinal teeth of which the posterior is bifid; in the left 
valve there are three cardinal teeth of which the central and largest is bifid. The 
margin is smooth. The sinus is high and widely triangular. 
Note. Clementia papyracea, Gray, has been taken at Singapore in shallow 
water (by Sv. Gap). 
Venerupis Irus L. . 
Donax Irus, Linné, Syst. Nat., ed. XII, 1767, p. 1128, No. 111. 
Venerupis Irus, Linnté, L. PreirrER in Marvint u. CHemnitrz, Conchyl. Cabin., XI Bd, 1 Abth., 1869, p. 
245, pl. 31, figs. 17-19. 
“= irus, Bucquoy, DaurzENBERG et Dotirus, Moll. mar. de Roussillon, II, p. 488, pl. 67, 
figs. 9—18. 
= macrophylla, DesHayes, Catal. of the Conchifera in the coll. of the British Museum, I, 1853, 
p. 193. Proc. Zool. Soc. London, 1853, Moll. pl. XVIII, fig. 8. 
= — — Sowersy, Thesaur. Conchyl., Il, p. 763, No. 2, pl. 165, fig. 20. 
= -— — Sowersy in REEVE, Conchol. icon., XIX, Venerupis, Sp. 23. 
Rupellaria — — PAGENSTECHER, Ueber d. v. Kossmann am Rothen Meere ges. Moll. 
1877, p. 42, No. 35. 
= RocHEBRUNE, Matér. pour la faune de l’Archipel du Cap Vert. Nouv. 
Arch. du Muséum, 2 Sér., Mémoires, IV, p. 255, No. 34. 
Venerupis — A. H. Cooke, Ann. and Mag. Nat. Hist., 1886, p. 108. 
Trus - MetviLt and STanpEN, Journ. of Conchol., IX, p..84. 
Venerupis -- HipaLGo, Fauna malacol. de 1. Isl. Filipin., Il, p. 321, No. 417. 
derelicta, Proc. Zool. Soc. London, 1853, p. 4, No. 17. 
— — -- Sowersy, Thesaur. Conchyl., Il, p. 765, No. 9, pl. 164, fig. 16. 
— — _ — in Reeve, Conchol. icon., XIX, Venerupis, Sp. 8. 
- — HipaLtco, Fauna malacol. de 1]. Isl. Filipin., I, p. 320, No. 415 
fimbriata, Sowrersy, Thesaur. Conchyl., II, 1855, p. 766, No. 12, pl. 165, fig. 23. 
in Reeve, Conchol. icon., XIX, Venerupis, Sp. 25. 
= attenuata, _ Reeve, Conchol. icon., XIX, Venerupis, Sp. 7. 
Koh Mesan, 15 fathoms, stones (°/2). Between Koh Mesan and Cape Liant, 
5—9 fathoms, sand ('/2). Coast of Lem Ngob, low tide, stones (*/2). North end of 
Koh Chang, 1 fathom, coral blocks (1). Koh Chang, 1—2 fathoms, old coral blocks (6). 
Koh Kahdat (?/2). 
Long. 1—14 mm. 
Distribution: — Singapore (shallow water, Sv. Gap), Madras, Bombay, Persian 
Gulf, Karachi, Aden, Red Sea, Suez, Mediterranean, Black Sea, Atlantic Ocean (the 
coast of Europe from England and Ireland to Cape Vert), Mauritius. — Annam 
(V. attenuata, Sow.), Philippines, Japan, Aru Isl. (V. attenuata, Sow.), Funafuti Atoll. 
