160 64 



older individual of L. squamosa, Lam., in which have developed, between some of 

 the central ribs towards the ventral margin, very slight indications of a rib; the 

 lines of growth also are somewhat prominent; these being individual characters, 

 the form can by no means be maintained as a variety. 



Fam. Ostreidae. 



Ostrea cucuUata, Born. 



Ostrea cuciilhild, Born, Testacea Musei Cæsarei Vindobon., 17H(), p. 114, pi. VI, figs. 11 — 12. 



var. Barclaijana, Sowerby. 

 Reeve, Conchol. icon., XVIII, 1871, Ostrœa, Sp. 77. 



Koh Chang, on stones at the strand (many specimens). Coast of Lem Ngob (2). 

 Coast of Koh Kahdat (1). 



Long. 35 mm., alt. 42 mm. 



var. Forskâli, Chemnitz. 

 Concliyl. Cabin., VIII, 1785. p. 150, pi. 72, fig. ()71. 



South of Koh Chuen, 30 fathoms, shells ('/a). Coast of Koh Chang (2). 



Long. 37 mm., alt. 55 mm. 



"Bangkok" (Coll. Dautzenberg). 



Young individuals of both forms were found in several places in the Gulf of 

 Siani. Ed. v. Martens records' that he has taken numerous specimens of 0. cuciillata, 

 Born, at Bangpra in the Gulf of Siam. 



Distribution: — Salanga, Mergui Archip., Nicobars, Ceylon, Bombay, Persian 

 Gulf, Gulf of Aden, Red Sea, Suez, Mozambique, Queriinba Isis., Mascarenes, coast 

 of Natal, Ascension Isl. — Poulo Condor, Cochin China, China, Formosa, Loo-Choo 

 Isis., Japan, Philippines, Sumatra, Moluccas, Timor, Thursday Isl., Mast Head Reef 

 (Queensland), South Australia (?Angas), Viti Isis., New Zealand. 



Deshayes,^ characterizes this oyster very correctly when he says that it "aurait 

 mérité le nom de multiformis" because its variability is exceedingly great, and 

 consequently, as maj' be expected, it has an endless number of synonyms;'^ to 

 these the following, besides many others, may doubtless be added: — 0. circiimsuta, 

 Gould, ^ 0. attenuata, Sow.,' and perhaps 0. vitre facta. Sow." Specimens of O. t«CJ/Z- 



' Zoolog. Ergebnisse ein. Reise in Niederl. Ost-Indien brsg. v. M. Webeh, IV, 1897, p. 223. 



^ Catal. d. Mollusques de l'ile de la Réunion, 18()3, p. ;i(). 



" For further details cf. Pagenstecheh, Ucber d. v. R. Kossmann am Rothcn Meere gesamni. Mol- 

 lusken, 1877, pp. 1(1 — 24. — Sturany, Lamellibrancbiaten d. Rothen Meeres, 1899, p. 37. — Lischke, Japani.sche 

 Meeres Concliyl., 11, p. ICI. — Cooke, Ann. and Magaz. Nat. Hist., Ser. ö, vol.17, p. 134. 



* Gould, Unit. States Kxplor. E.xpedit., pi. 43, fig. 576. ~ Reeve, Concliyl. Cabin., XVIII, (hliea, 

 Sp. Ü4. Why Reeve records "Massachusetts?" as its habitat is difficult to understand, as Gould (Proc. 

 Boston See. of Nat. Hist., 1850, p. 346) says that his species was found in the "Feejee and Samoa Is- 

 lands." Angas (Proc. ZooI. Soc. London, 1867, p. 934) records it from Botany Bay. 



■' Reeve, loc. cit. Sp. 49. 



'^ Reeve, Ioc. cit. Sp. 8U. 



