97 193 



Sound of Koh Chang, 5 fathoms, soft clay ('/i). Koh Mak, sandy coast (Vi). 

 Between Koh Chuen and Koh Chang, 15 fathoms, mud (2). Between Koh Kut and 

 Koh Kahdat, 10 fathoms, shells ('/.•). W. of Koh Kut, 30 fathoms, sand and mud (Vi). 



Long. 6-5—13 mm. (long. 13 mm., alt. 10 mm.). 



Distribution: — Karachi (Melvill & Standen). — Philippines, Japan, Upolu 

 (Mus. Godeffroy). 



The figures in Römer's Monograph (pi. 24, figs. 1—3) bear no resemblance 

 whatever to T.niix, Hani.; they undoubtedly represent quite a different species. 



Tellina (Arcopagia?) casta, Hani. 



Tellina casta, Hanley, Proc. Zool. Soc. London, XII, 1844, p. 63. 



— — — SowERBY, Thesaur. Conchyl., I, p. 253, No. 57, pi. 56, fig. 9. 



— — -- Reeve, Conchol. icon., XVII, Tellina, Sp. 269. 



— (Arcopagia' casta, Hanley, Römer in Martini u. Chemnitz, Conch}'!. Cabin., X Bd., 4 Abtli., p. 95. 

 Arcopagia casta, Hanley, V. Bertin, Revision d. Tellinidés, p. 323, No. 21. 



Tellina (?) casta, — Edg. Smith, Lamellibianchiata of the Challenger Exped., p. 109. 



E. of Koh Chuen, 9-10 fathoms, shells (1). Gulf of Rayong, 7—10 fathoms, 

 sand and mud (3 + '/a). S. of Koh Samit, 20 fathoms, mud (1). Koh Kahdat, 

 1 — 10 fathoms, mud, sand and clay (5 + ^''/s). W. of Koh Kut, 15 fathoms, mud (2). 



Long. 5 — 16 mm. 



Distribution: — Singapore (Hanley; Danish Exp. to Siam, 2 — 3 fathoms, 

 coral-reef (5); Sv. Gad, shallow water), Mergui Archipel. — Torres Strait, Tonga Isis., 

 Upolu (Mus. Godeffroy). 



The present species is easily distinguishable from forms allied to it, by the 

 left valve being more convex than the right; it is always quite white in colour. The 

 specimens from the Gulf of Siam are more oblong than the figures given by Reeve 

 and SowERBV; the height of an individual, 13 mm. long, is 10 mm. 



Tellina (Arcopagia?) declivis, Sow. 



Tellina ilcclivis, Sowerhy, Reeve, Conchol. icon., vol. 17, 1868, Tellina, Sp. 261. 

 Arcopagia declii'is, Sowerry, V. Bertin, Révision d. Tellinidés, p. 324, No. 25. 



W. of Koh Chang, 30 fathoms ("«). Koh Kahdat, at the strand (^/a). Between 

 Koh Kut and Koh Kahdat, 10 fathoms, shells {"h). W. of Kut, 15 fathoms, mud ('/a). 



Long. 5 — 10 mm. (long. 10 mm., alt. 85 mm.). 



Distribution unknown. (Singapore, 2 — 3 fathoms, coral-reef (1 right valve), 

 Danish Exp. to Siam). 



My specimens exactly agree with Sowerby's description and figure; they are 

 easily distinguished from T. pudica, to which species they are most closely allied, 

 by the greater convexity, and by the predominance of the height of the valves in 

 comparison with their length. 



11 K 1>. Vi.lnisL Sclsli. Sl;r.. 7. R.eliUc nntiirviilen- 1,. n;, ni:illicni Afcl. V. 3. 25 



