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



I recognize two forms which I define as follows : — 



Hydrophis fasciatus fasciatus. 

 27 to 33 scales round the neck. 47 to 58 round the 

 body. Ventrals 400 to 504 (531, Wall). Av. 455. 



Habitat. Coasts of India and Burma to the Malay 

 Archipelago. 



Hydrophis fasciatus atriceps. 



25 to 30, usually 27 to 29, scales round the neck. 40 

 to 49, usually 43 to 45, round the body. Ventrals 327 to 

 452. Av. 366. 



Habitat. Gulf of Siam and South China Sea to Malay 

 Archipelago. 



Both forms appear to extend their distribution into the 

 seas of the Indo-Australian Archipelago, but the particular 

 range of each one has yet to be determined. 



Hydrophis fasciatus fasciatus. 



The type specimens are in the Berlin Museum. Their 

 habitat is unknown. Dr. Nelly de Rooy has kindly made 

 enquiries for me and she is informed that they have 29 and 

 30 scales round the neck, 52 and 53 round the body, and 

 457 ventrals. This description accords with the form found 

 west of the Malay Peninsula, and shoukl therefore be 

 designated the typical one. 



The figures I have given above for this form, are based 

 chiefly upon my series from the Straits of Malacca, but all 

 the specimens that I have examined from the Indian coast 

 also agree with them. Wall records examples from India 

 with a lower body count, but as he enumerates at mid-body, 

 another 3 or 4 may be added to his figures to arrive at the' 

 maximum number. Boettger records two specimens from 

 Madras with 52 and 56 respectively. 



This range of variation will also include H. rhombifer 

 BIgr., (56 scales round the body, type locahty coast of 

 Perak), and //. leptodira Blgr. (58 scales round the body, 

 type locality Mouth of the Ganges* ?), and that his two 

 forms should now become synonyms of fasciatus, Mr. 

 Boulenger is agreed. Wall, in his Monograph, came to this 

 same conclusion, but in his conception of the species has 

 included H. hrookii Giinther, a snake which I believe to be 

 quite distinct. 



Further collections from the coast of India may possi- 

 bly inodify the definition of this form as given above, but 

 it will not alter the separation of the Malaccan race as 

 distinct from that found in the Gulf of Siam. 



Variation. — The following remarks concern my series 

 from the Straits of Malacca. The rostral is as high as 

 broad in one example ; the frontal is shorter than its dis- 

 tance to the rostral in two examples ; two postoculars occur 

 in two examples ; the praefrontal shields fail to touch the 

 supralabials on both sides in three examples, and on one 



*Tlie record is Cantor's and possibly in error. 



