266 aoe 
E. of Cape Liant, 9 fathoms, shells (5). Gulf of Rayong, 7—10 fathoms, sand 
and mud (2). S. of Koh Samit, 14—20 fathoms, mud (6). S. of Koh Tulu, 10 
fathoms, mud (2). W. of Koh Chang, 20 fathoms, mud (‘/2). N. of Koh Kahdat, 
4—5 fathoms, coarse sand (1). Koh Kahdat, 1—5 fathoms, sand (1). Between Koh 
Kahdat and Koh Kut, 6—10 fathoms, mud mixed with sand (°/2). Koh Mak, sandy 
coast (7/2). S. of Koh Mak, 5—6 fathoms (2). W. of Koh Kong, 10—15 fathoms (1). 
Long. 8—24 mm. 
Distribution:— Singapore, Strait of Malacca, Mergui Archip., Andamans, off 
Port Blair, Andaman Isls., 100 fathoms (Epa. Smirn), Gulf of Manaar. — Poulo 
Condor, Philippines, Formosa, Strait of Macassar, New Guinea, Torres Str., Mast 
Head Reef (Queensland), Port Essington, Dampier’s Land (NW. Australia), NE. Australia. 
The specimens, for the most part, are thick-valved and vary greatly in form, 
but quite thin-valved specimens also occur; thus, for example (from Singapore) a 
left valve of the following dimensions:— long. 19 mm., alt. 7 mm., crass. 4 mm.;, 
it is very thin-valved, and without a trace of the denticulation upon the dorsal and 
ventral margins characteristic of the species; it greatly resembles Epc. Smirn’s 
species C. Macgillivrayi, and like the latter it has a shallow depression down the 
middle (which C. crassa also very frequently has); the hinge characters are also less 
pronounced than in the thick-valved specimens of C. crassa of the same size, from 
which it appears to differ greatly, but it is, in reality, only an unthickened individual. 
Corbula (Aloidis) tunicata, Hinds. 
Corbula tunicata, Hinps, Proc. Zool. Soc. London, 18438, p. 55. 
— — —_ Reeve, Conchol. icon., Il, Corbula, Sp. 5. 
= = Zoology of the voyage of “Sulphur,” Mollusca, p. 68, No. 281, pl. 20, figs. 4—5. 
= = = Epa. Smiru, Lamellibranchiata of the Challenger Exped.. p. 29. 
= Prircuarp and Gar irr, Proc. Roy. Soc. Victoria, vol. 16, 1903, p. 101. 
- scaphoides, — Proc. Zool. Soc. London, 18438, p. 56. 
- = ReEEve, Conchol. icon., IH, Corbula, Sp. 24. 
Epa. Smirn, Lamellibranchiata of the Challenger Exped., p. 32, pl. 7,, fig. 3. 
- Prircuarp and Gariirr, Proc. Roy. Soc. Victoria, vol. 16, 1903, p. 101, 
NW. of Koh si Chang, 10 fathoms, mud (1). Gulf of Rayong, 7—10 fathoms, 
mud (‘/2). Sound of Koh Chang, 5 fathoms, soft clay (‘/2). West coast of Koh 
Chang, 10 fathoms, mud (7/2). S. of Koh Bidang, 9 fathoms, mud (1). S. of Koh 
Mak, 5—6 fathoms (4). Between Koh Kahdat and Koh Kut, 6—10 fathoms, mud 
mixed with sand (*/2). N. of Koh Kut, 10 fathoms, mud (7/2). W. of Koh Kut, 
15 fathoms, mud (3). 
Long. 7—25 mm. (long. 25 mm., alt. 17 mm., crass. 14 mm.). 
Distribution: — (t. = tunicata, Hinds; s. = scaphoides, Hinds). Singapore (s.), 
Mergui Archip. (¢.), Ceylon (s.), Cape of Good Hope (¢.). — Philippines (1. s.), China 
Sea (¢.), Hong Kong Harbour (s.), Amboina (t.), Strait of Macassar (¢.), Arafura 
Sea (t.), Torres Strait (t.s.), Cape York (s.), Port Jackson, Sydney (¢.s.), Mast Head 
Reel, Queensland (s.), Port Molle, Queensland (¢. s.), Victoria (t. s.), Port Darwin, 
NW. Australia (1), Tasmania (s.). 
