103 199 
Off Koh Kam, 10 fathoms, gravel (‘/2). Between Koh Mesan and Cape Liant, 
5—9 fathoms (‘/2). Between Koh Kut and Koh Kahdat, 10 fathoms, shells (7/2). 
Long. 6—9 mm. (long. 9 mm., alt. 7 mm.). 
Distribution: — Karachi, Mekran coast, Persian Gulf, Durban,’ — Philip- 
pines, Torres Strait, Flinders Passage, Viti Isls. 
Sowerpy’s figure in REEveE’s “Conchol. icon.” (pl. 41, sp. 232), which Epa. Smirn 
regards as “bad,” agrees fairly well with the individuals from the Gulf of Siam, 
and although it is not perfectly typical, yet it can be recognised; besides, it agrees 
well with Sowersy’s original figure in 
“er 
Phesaurus Conchyliorum.” 
Tellina (Moerella) semitorta, Sow. 
(Pl. III, Figs. 43—46). 
Tellina semitorta, SowErBy, REEVE, Conchol. icon., XVII, 1867, Tellina, Sp. 221. 
— (Mera) semitorta, Sowrrsy, ANGAS, Proc. Zool. Soc. London, 1867, p. 919. 
— (?) — — Eve. Smiru, Report on the Lamellibranchiata of the Challenger 
Exped., p. 111. 
—  (Donacilla) semilorta, Sowrersy, MEtyitt & STANDEN, Journ. Linn. Soc. Zool., XXVII, p. 201. 
_- V. Bertin, Révision d. Tellinidés, p. 263, No, 81. 
Between Koh Rin and Cliff Rock, 15 fathoms (7/2). Koh Kram, 30 fathoms (*/2). 
N. of Koh Kam, 5 fathoms, gravel (4 + */2), Off Koh Kam, 10 fathoms, gravel ('/2). 
Between Koh Mesan and Cape Liant, 5—9 fathoms (12). North side of Koh Mesan, 
10—15 fathoms, stones (*/2). Gulf of Rayong, 7—10 fathoms, sand and mud (1 +- 7/2). 
Between Koh Kut and Koh Kahdat, 10 fathoms, shells (‘/2). W.of Koh Kut, 15—30 
fathoms, mud (1 + 2/2). Koh Kahdat, 1—5 fathoms, sand (2 + */2). 
Long. 2°55—12 mm. 
Distribution: — Singapore (low water, Sv. Gap). Torres Strait, Port Jackson 
(Sydney), Watson’s Bay (New South Wales). 
This species varies considerably in form; on PI. III, Figs. 483—46, I have 
given several instances of this;* the sculpture, also, is very variable. Thus, for in- 
stance, the concentric striation may be more or less close-set; and the place where 
the less close-set, posterior striation meets the rest of the valve-sculpture is often situated 
very far back, while in other specimens it may be at about the middle of the valve; 
and often the more prominent lamellar sculpture upon the posterior end has al- 
most entirely disappeared, and the sculpture is nearly uniform over the whole 
surface of the valve. Nor is the striation, as a rule, the same on both valves. The 
tortuosity of the posterior end of the valves, mentioned by Epa. Smrru (loc. cit., p. 112), 
is in one specimen directed towards the right, and in another towards the left. 
SmirH’s statement that: “the anterior lateral teeth and the plate supporting the 
ligament are tinged with pale-red,’ is not found in the specimens from the Gulf 
1 Epa. Smiru, Proc. Malacolog. Soc. London, vol. 5, p. 400. 
2 Epc. Smiru’s criticism of Sowersy’s figure in ReEve’s “Conchol. icon.” is unjustified; several 
specimens from the Gulf of Siam have the form shown in Sowersy’s figure. 
