6 Journal of the F.M.S. Museums. [Vol. X, 



colour form (bicolor), the yellow merging by every degree 

 of intensity into brown. 



(Straits of Malacca series). Two out of the nine 

 examples obtained (Nos. 3903, 3915) are coloured as 

 above, but the remaining seven are quite different. They 

 have a narrowish black dorsal band occupying about ten 

 scales, while the rest of the body is yellow, thickly spotted 

 with black. In the fore-part of the body the upper spots 

 have coalesced to form a narrow stripe, so that there is 

 alternately a dorsal band, a narrow yellow stripe, and then 

 a black one. The dorsal band in the hinder part of the 

 body is sinuous in out-line or is broken into large spots. 

 Tail thickly spotted, with the central or ventral part entirely 

 black. In some examples the whole head is dark brown or 

 black. 



I regard these as Boulenger's form B (Jan's maculata) . 

 They shew no tendency whatever to intergrade with the 

 previous form. 



In addition to the difference in colour, the Straits series 

 shews a higher average number of scale rows round the 

 neck and body, than those from the Gulf. The variatiqc 

 is as follows : — 



Gulf of Siam. 



39 to 50 round the neck ; 48 to 60 round the body. 



Straits of Malacca. 



44 to 55 round the neck ; 52 to 68 round the body. 



The question of racial distinction in this widely 

 distributed snake is a complex one. Boulenger describes 

 seven colour varieties, but does not attempt to connect them 

 in any way with geographical areas. Barbour, with the 

 additional material available in the Harvard College 

 Museum says "nine easily distinguishable color phases 

 may be recognized." Six of these, he adds, occur in and 

 about the Bay of Panama. 



I do not tliink he has sufficiently proved that his Hydrus 

 platurus ornatus is entitled to subspecific rank. Its habitat 

 he defines as the East Indian Archipelago, and his own 

 specimen (No. 938) came from Singapore. But, as shewn 

 by my two series, we may expect to find in the same 

 locality at least three other colour forms, namely, 

 Boulenger's B. D. and E. 



Hydrophis lamberti Smith. 



Journ. N. H. S. Siam, ii, p. 340 (1917). 



Description of the type. — Head rather large, neck 

 thick, body moderately elongate. Eye a little larger than 

 its distance from the niouth ; rostral considerably broader 

 than deep, the portion visible above equal to one-third the 

 length of the internasal suture ; frontal once and a half 

 as long as broad, much shorter than its distance from the 



