134 38 
fathoms, soft clay (1). W. of Koh Chang, 20 fathoms, clay (1). S. of Koh Kahdat, 
8—10 fathoms, mud (2). W. of Koh Kut, 30 fathoms, sand and mud (1). 
Long. 4—35 mm. 
Distribution: — Mergui Archip., Suez. — Canton, East Australia (the districts 
around Sydney). ! 
The specimens from the Gulf of Siam are all provided with a very shiny, 
greenish epidermis and several were either completely or partly hidden in their 
“nest” of byssus-threads, and fragments of shells, pebbles, ete. were partly attached 
to and partly entangled in these threads. Modiola perfragilis, Dunk.,” M. Japonica, 
Dunk., M. angusta, Cless.,* and M. cultellus, Desh.,* are closely allied species. Pro- 
fessor Ep. v. MarTENS, to whom I sent some specimens of the present species from 
Koh Samit, writes as follows: “Modiola perfragilis “Reeve” von d. Molukken ‘ist 
wohl Jugendzustand von glaberrima.”’ 
Brachyodontes (Hormomya) subramosus, Hanl. 
Modiola subramosa, HANLEY, Proc. Zool. Soc. London, XII, 1844, p. 14. 
== = — Catalogue of rec. bivalve shells, 1842—56, p. 241, pl. 24, fig. 30. 
— — Reeve, Conchol. icon., X, Modiola, Sp. 43. 
— -= — Marrini u. CHemnitTz, Conchyl. Cabin., Vill, 3 Abth., p. 121, pl. 31, fig. 11. 
= -= — vy. Martens, Siiss- u. Brackwasser Moll. d. Ind. Archip., 1897, p. 226. 
—_— ramosa, CLESSIN, Martini u. CHEMNITZ, Conchyl. Cabin., VIII, 3 Abth., p. 134, pl. 26, fig. 8. 
West coast of Koh Chang, 1 fathom, old coral ‘blocks (4). Koh Kahdat, 1 
fathom, sand (1). 
Long. 7 mm. 
Distribution:— Mindanao and Samar, Philippines (Cumrne and Jacor), 
Ternate, Moluccas (DuUNKER’s collect.), Celebes (PATEL’s collect.), the Gulf of Amboina 
(Rumpu and vy. Martens), Sorong (TAPPARONE CANEFRI), New Caledonia (FRAUENFELD). 
According to y. MARTENS,’ it is said to be able to live in brackish water and 
(in the Phillipines) perhaps even in freshwater. F.P. Marratr® records it (but this 
is surely an error) as obtained by the “Argo Expedition” at Abaco (Bahama Islands). 
Swartnson’s name Brachidontes, as a sub-genus of Modiola, was altered to Brachy- 
dontes by P. Fiscuer, and afterwards by JuKkEs-BRowNE’ to the generic name 
Brachyodontes. 
1 FE. vy. Marrens, Stss- u. Brackwasser Mollusken d. Indisch. Archipels, p. 87. 
’ It is strange that Dunker (Proc. Zool. Soc. Lond., 1856, p. 362) in his diagnosis of this species 
from Cumine’s collection says: “testa... parum splendida.” Rerrve, on the contrary, characterizes the 
same specimens as “shining” (nitente). 
’ Probably identical with M. perfragilis, Dunk. 
4 Magaz. de Zoologie éd. p. Guérin-Méneville, II, 1840, pl. 13, “from Kamtschatka” is undoubtedly 
synonymous with M. glaberrima, Dunk. 
5 Loc. cit. p. 226. 
® Hiaains and Marrarr, Mollusca of the Argo Expedition to the West Indies, 1876, Liverpool 
Museum Report, No. 1, 1878, p. 423. 
7 Proceed. Malacolog. Soc. London, vol. VI, 1905, pp. 221—23. 
