126 30 



Area tjubcinaciilum, Hiiiivii, Mautini u. Chemnitz, Conchyl. Cabin,, VIII, 2 Abtli., p. 1U7, pi. 28, ligs. 5—6. 



— — — P. Fischer, Catal. d. Moll, de Ilndo-Cliine, p. 272. 



— [Antidara; giibernaculum, Rrkvk, Lamy, .louni. de Conchyl., vol. ,'>5, 19U7, p. 23!). 



— chdlciinllunn, Ki;kvi;, I'roc, Zool. Soc. London, XII, 1844, p. 44 (fide Edg. Smith). 



— — — Conchol. icon., II, Arcix, Sp. 43. 



— Lnzonica, Rkevi;, Proc. Zool. Soc. London, XII, 1844, p. 44 (fide Edg. Smith). 



— — — Conchol. icon., II, Area, S. 44. 



"Golfe de Siam," L. Morlet (P. Fischer loc. cit.). 



The Danish Expedition collected no specimens of this species in the Gnlf 

 of Siam. 



Dist libntion: — Philippines, China, Formosa, Port Jackson. 



Area (Scapharca) indica, Gm. 



(PI. II, Figs. 5-12). 



Area indica, Gmhlin, Syst. Nat., ed. XIII, 1790, p. 3312, No. 27 (excl. var.). 



( — — — Lamarck, Anim. sans vert., VI, p. 473, No. 31). 



( — — — Reevk, Conchol. icon., II, Area, Sp. .'Sfi). 



— — — Martini u. Chemnitz, Conchyl. Cabin., VIII, 2 Abth., p. 11, pi. 2, fig. 2. 



— (Argina) indica, Gmei.in, Lamy, Journ. de Conchyl., vol. 55, 1907, p. 295. 



— Inditte Orientalis, Chemnitz, Conchyl. Cabin., VII, 1784, p. 196, pi. 55, fig. 543. 



Oslindisehe Bastariaretie, Martini, Beschäftig, d. Heilin. Gesellsch. Naturf. Freunde, III, 1777, pp. 288—90, 

 pi. 6, fig. 13. 



Coast of Lem Ngob (''/a). 



Long. 21-44 mm., alt. 11—23 mm. 



Distribution: — Coromandel Coast (Tranquebar; Chemnitz). Hanley' records 

 the species from Sumatra. In the Museum in Berlin are specimens from Sumatra; 

 North-west Australia (Menke). This species is probably more widely distributed. 



By comparison with original specimens of Area indica, Gm., from Tranque- 

 bar, from Spengleh's collection in the Zoological Museum of the University of 

 Copenhagen, I have been able to identify the specimens from the Gulf of Siam. 

 The present species has hitherto been badly figured and described. Lamarck, 

 Reeve and Kobelt,^ all say, that the area is absent in the species; this is nol 

 correct (Gmelin also does not mention it). Normally, there occurs an area which 

 is rather narrow and striped' as shown in the figures, PI. II, Figs. 9 and 12; it 

 is, however, frequently reduced to a minimum, and as the valves, thereby, have 

 their unibones placed closely together, Ihe latter become much worn; [he hinge- 

 teeth also suffering by this reduction of the area. The ribs, 30 — 36 in number, 

 are flattened and broad. From the umbones downwards to the ventral margin the 

 valves are frequently somewhat concave in the middle. Reeve's figure certainly 



' Catalogue of recent bivalve shells, p. 158. As Hani.ey in mentioning this species says: "with 

 many ribs, which are grooved in the middle" it can hardly be the present species. 



'' Martini & Chemnitz, Conchyl. Cabin., loc. cit. 



^ Chemnitz (loc. cit., VII, j). 197) says: "Der kleine zwischen den Wirbehi befindliche, etwas ver- 

 tiefte Kaum wird von einen schwärzlichen lederartigen Bande bedecket." 



