A MONOGRAPH OF THE SEA-SNAKES (HYDROPHTINM). 



231 



juxtaposed, and ventrals 427. The latter is from another specimen of mine from the 

 same locality in which the costals are anterior 38, midbody 48, posterior 42 juxtaposed , 

 and ventrals 398. Rostral, — the portion visible above from half to three-fifths the 

 internasal suture. Praef r on tals,— touch the second supralabial. (This contact 

 fails in one example on both sides, and in two others on one side). Postoculars, 

 — one. (In one example there are two on one side, and in another three on one side). 

 Temporals,— usually one large anterior shield, and sometimes a subequa 1 posterior 

 one. (There are two superposed anterior on one side in two specimens, and on both 

 sides in one). Supralabials, — seven or eight, the anterior four, five or six entire ; 

 the third and fourth touch the eye (The fifth also in at least four examples). 

 Inf r a labials,— four, the last in contact with three or four scales behind, the suture 

 between the first usually less than that between the anterior sublinguals. Marginals, 

 one or more after the third (sometimes the second) infralabial. Sublinguals, — 

 two well-developed pairs, the fellows of the posterior as frequently separated as in 

 contact. Costals ,— anterior 30 to 41, midbody 37 to 54, posterior 34 to 46; 

 subimbricate, or juxtaposed posteriorly. Ventrals, — 310 to 438; mostly entire; 

 twice or less than twice the breadth of the last costal row. 



Colour. — Olivaceous dorsally merging to yellow ventrally. From 40 to 65 black 

 rings surround the body, which gradually lack definition with increasing age. Some 

 of these are interrupted costally sometimes, especially the posterior ones. At midcosta 

 the rings are about as broad as the spaces. Head mottled above with yellow and black. 



Habitat. — All are from coasts between the Gangetic Delta and Borneo. By far 

 the majority of specimens are from the Burmese Coast. 



DlSTIRA C^RTJLESCENS (Shaw). 



Hydrus caerulescens, Shaw , Zool., 1802, iii, 561. 



Hydrophis cserulescens, Gray in Zool. Misc., 1842, p. 62, and Cat., 1849, P- 55- 

 tJ Gilnther, Rept. Brit. Ind., 1864, p. 365, pi. xxv, fig C. 



Boulgr. in Blanford, Fauna Brit. Ind. Rept and Batrach , 

 1890, p. 400. 

 ,, Boulgr., Cat. Brit. Mas., 1896, iii, p. 275. 



f} ,, Sclater, List Snakes Ind. Mus., 1891, p., 62. 



Hydrophis obscurus, Sclater, loc. cit., p. 63, Nos. 11498 and 11499. 

 cyanocincta, Sclater , loc. cit., p. 66, No. 8242. 



B 



Fig. 45. — Distira caerulescens. 



