97 193 
Sound of Koh Chang, 5 fathoms, soft clay (‘/2). Koh Mak, sandy coast (1/2). 
Between Koh Chuen and Koh Chang, 15 fathoms, mud (2). Between Koh Kut and 
Koh Kahdat, 10 fathoms, shells (*/2). W. of Koh Kut, 30 fathoms, sand and mud (?/2). 
Long. 65—13 mm. (long. 13 mm., alt. 10 mm.). 
Distribution:— Karachi (MeLtvitt & STanpEN). — Philippines, Japan, Upolu 
(Mus. Godeffroy). 
The figures in R6mEr’s Monograph (pl. 24, figs. 1—3) bear no resemblance 
whatever to T. nux, Hanl.; they undoubtedly represent quite a different species. 
Tellina (Arcopagia?) casta, Hanl. 
Tellina casta, HANLEY, Proc. Zool. Soc. London, XII, 1844, p. 63. 
= — -- Sowersy, Thesaur. Conchyl., I, p. 253, No. 57, pl. 56, fi 
= — — REEVE, Conchol. icon., XVII, Tellina, Sp. 269. 
_ (Arcopagia) casta, HANLEY, ROMER in MARTINI u. CHEMNiITz, Conchyl. Cabin., X Bd., 4 Abth., p. 95. 
Arcopagia casta, Haniry, V. Bertin, Révision d. Tellinidés, p. 323, No. 21. 
Tellina (?) casta, — Epe. Smiru, Lamellibranchiata of the Challenger Exped., p. 109. 
go. 
5 
E. of Koh Chuen, 9—10 fathoms, shells (1). Gulf of Rayong, 7—10 fathoms, 
sand and mud (3 + 14/2). S. of Koh Samit, 20 fathoms, mud (1). Koh Kahdat, 
1—10 fathoms, mud, sand and clay (5 + 7%/2). 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. Gap, shallow water), Mergui Archipel. — Torres Strait, Tonga Isls., 
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 Sowersy; the height of an individual, 13 mm. long, is 10 mm. 
Tellina (Arcopagia?) declivis, Sow. 
Tellina declivis, SowERBY, REEVE, Conchol. icon., vol. 17, 1868, Tellina, Sp. 261. 
Arcopagia declivis, Sowrersy, V. Bertin, Revision d. Tellinidés, p. 324, No. 25. 
W. of Koh Chang, 30 fathoms (‘/2). Koh Kahdat, at the strand (*/2). Between 
Koh Kut and Koh Kahdat, 10 fathoms, shells (7/2). W. of Kut, 15 fathoms, mud (*/2). 
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 Sowersy’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 iength. 
D. KD. Vidensk. Selsk. Skr., 7. Reekke, naturvidensk. og mathem. Afd. V. 3. 25 
