n9 



DESCRIPTION OF A NEW SEA-SNAKE FROM RANGOON. 



By G. a. Boulenger, f.r.s. 



( With a Plate). 



(Read before the Bombay Natural History Society on 12th 



August 1902). 



DISTIRA HENDERSONI. 



Head small ; body much elongate ; neck slender, its diameter about 

 one-third the greatest depth of the body. Rostral much broader than 

 deep; nostril pierced between two nasals and an internasal; the internasals 

 small, separating the posterior nasals and followed by a small azygous 

 shield separating the praafrontals anteriorly ; frontal hexagonal, large, 

 nearly three times as long as the anterior nasals, one and a half as long 

 as broad, as long as its distance from the end of the snout ; parietals a 

 little longer than the frontal ; two prse and two postoculars ; two subocu- 

 lars, on the left side, separate the eye from the labials ; two or three 

 superposed anterior temporals ; eight upper labials, second largest, 

 fourth, on the right side, entering the eye ; two pairs of very short 

 chin-shields, the second pair separated by scales. 32 scales round the 

 neck, 44 round the body ; scales feebly imbricate, feebly but very 

 distinctly keeled. Ventrals very feebly enlarged, feebly bicarinate, 817. 

 Olive above, bright yellow on the sides and beneath ; 54 regular black 

 rings, about half as wide as the spaces between them, on the body, 

 these rings widening into rhombs on the back; 7 black rings on the tail ; 

 a regular pt.ttern of black streaks on the head, one across the occiput 

 connected with the first riug by a median streak and sending forwards 

 two loop-shaped streaks, one on each parietal shield ; a curved black 

 streak from the first labial shield to the angle of the mouth, bordering 

 the eye below ; a black cross-bar on each side of the throat, behind the 

 occipital bar. 



Total length 940 millimetres. 



A single specimen, a gravid female from the Coast of Rangoon 

 presented to the British Museum by Dr. T. Beath Henderson, of 

 Glasgow, who received it from a friend. This is a very well-marked 

 new species, in its aberrant upper head-shields connecting Distira with 

 Thalassophis and recalling Platurus in its bright, regular colouration. 

 Its nearest allies appear to be Thalassophis anomalus, Schmidt, from 

 Java, which is only known to me from the descriptions and figures, 



and Distira lapemidoides. 

 11 



