17 113 



he refers Area lactea var. eryihraea, Issel, from the Red Sea to A. deciissatct. Reeve 

 (Sow.), as stated by A. H. Cooke,' it is in reality only a form of A. lactea L. — 

 Lamy in his latest revision of the gen. Arca^ regards A. complanata, Ch., somewhat 

 difVerently from the way in which I regard it here. He gives A. velata, Sow., as a 

 variety of A. complanata, Ch. (which he names A. nivea, Ch.), and places A. decassata 

 as a distinct species; but as Lamy's work was not published until I had finished 

 my work upon the Area-group, I have not been able to consider it here. 



Area (Barbatia) lima, Reeve. 



Area lima, Reeve, Proc. Zool. Soc. Lond., XII, 1844, p. 125. 



— — — Conchol. icon., II. Sp. 101. 



— {Barbatia) lima. Reeve, Martini u. Chemn., Conchyl. Cabin., VIII, 2 Abtli., p. 115, pi. 30, figs. 5-6. 



— — — — Edg. a. Smith, Lamellibrancliiata of tlie Challenger Exped., p. 2G0. 



— — — — — Report on the zoolog, collect, made during the voyage of 



H. M. S. "Alert," p. 110. 



— — — — E. Lamy, Bull, du Mus. d'Hist. Nat. Paris, 1904, p. 273. 



— decussata, Sowekby var. lima, Reeve, Lamy, Journ. de Conchyl., vol.55, 1907, p. 65. 



Koh Kram, 6—10 and 30 fathoms (3). E. of Koh Chuen, 9—10 fathoms, shells (2). 

 Koh Chuen, 10—15 fathoms (2). S. of Koh Chuen, 30 fathoms, shells (■'/a). OtT 

 Koh Kam, 10 fathoms, gravel (1). Gulf of Rayong, sand, mud and shells (1). 

 North and west coast of Koh Chang, 1 fathom, old coral blocks (12). Koh Kahdat, 

 1 fathom, sand (2). W. of Koh Kut, 30 fathoms, sand and mud ('/s). Between Koh 

 Kut and Koh Kahdat, 10 fathoms, shells (5). S. of Koh Kahdat, 8—10 fathoms, mud (2/2). 



Long. 3—45 mm. 



Distribution: — Singapore (low water, Sv. Gad), Madras, Gulf of Manaar, 

 Laccadive and Maldive Archipel., Gulf of Aden, Red Sea (pleistocene). — Philip- 

 pines, Torres Str., Port Molle, St. Vincent's Gulf, South Australia, South. Paumotu Isis. 



The following species may safely be reckoned as synonymous with Area lima, 

 Reeve: — Barbatia oblonga, Dkr. ■' (non Anomalocardia oblonga, Phil, et Dkr.), Area 

 granulata, Phi\.,^ from the Sandwich Islands, Barbatia (Acar) aeerœa, Melv. & Stand.'' 

 Edg. a. Smith "^ slates that A. trapezina, Lam. ("as determined by Reeve"), is probably 

 a form of A. lima. Reeve; how far trapezina, Lam., is on the whole a form 

 of A. lima I am not at present prepared to say; that the whole ßarZ)ah'a-group — 

 when, later, a larger quantity of material is at hand and further comparative in- 

 vestigations have been carried out — will unquestionably be reduced in many 

 respects, is practically certain. In many cases it is very difficult to determine young 

 specimens of A. lima and to keep them distinct, as for example from A. complanata, 



' Annals and Magazine of Nat. Hist., 5. ser., vol.18, 1880, p. 93. 



- Journ. de Conchyliologie, vol.55. 1907, p. 59. 



■' Novitates Conchologicae, p. 107 and p. 85. 



^ Abbild, und Beschreib, neuer od. wenig gekannt. Conchyl., Ill, p. 114 (22), pi. VI. lig. 3. 



■ Journ. Linn. Soc. Zoology, vol. XXVII, p. 180, pi. 10, lig. 15. 



'■ Proc. Zool. Soc. London, 1891, p. 431. 



I). K, II, Viilfilsk. Selsk. Skr.. 7. Ha-kke, nalurviilensk. oj! niiithem. Al'il V. 3. 15 



