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



Hudrophis viperinus, N. de Rooij, Kept. Ind. Aust. Archipet. 

 il, p. ^31 C1917). 



Gulf of Siam, 17 exs. Cap St. Jacques, Cochin China, 

 2 exs. 



One of the specimens was seen to fall from the claws 

 of a fishing eagle, and was picked up still alive and quite 

 undamaged at some distance inland. This incident possibly 

 explains the records of sea snakes which have been occa- 

 sionally discovered at a considerable distance from their 

 natural habitat.* 



For a small series, mine shew a wide range in the 

 number of scale rows. They vary from 27 to 34 at the 

 neck and from 37 to 50 round the body. Ventrals 181 to 

 264. A reference to the table will show that the extremely 

 low ventral count of 181 is confined to a single individual. 

 No. 2716. But for this specimen the variation in the 

 number of these shields would be 232—264, a range which 

 is almost exactly in accordance with what has been already 

 given by Boulenger and Wall. It is an excellent example 

 of the abnormality in ventral shields to which I have refer- 

 red in the preliminary remarks. 



As shewn by the table, the two specimens from Cochin 

 China have a higher body count than any found in the Gulf. 



Colouration. — Grey above, white below, with from 28 

 to 34 dark grey dorsal rhombs which are usually confluent 

 vertebrally. My one juvenile is beautifully and con- 

 spicuously marked, but with age the pattern becomes 

 obscured, and in some individuals has entirely disappeared, 

 leaving the back of a uniform grey colour, which is 

 separated from the white of the belly by a clear line of 

 demarcation. 



Dentition. — Posterior maxillary, 5 ; palatine, 7 or 8 ; 

 pterygoid, 14 to 17 ; mandibular, 17 (4 specimens 

 examined) . 



Hydrophis jerdonii (Gray); 



Hydrophis jerdonii, Giinther, Rept. Brit. Ind., p. 362 (1864) ; 

 Bouleng., Cat. Sn. B. M., Ill, p. 299 (1896) ; idem, Fauna Malay 

 Pen., Rept. and Batr., p. 186 (1912) ; N. de Rooij, Rept. Ind. Aust. 

 Archipel., II, p. 232 (1917). 



Distira jerdonii. Wall, Mem. Asiat. Soc. Bengal, II (8), p. 241 

 (1909). 



Singgora, 3 exs. 



Variation. — The anterior temporal reaches the labial 

 margin on both sides in one example, and on one side in 

 another. Chin-shields well developed (as figured by 

 Giinther, pi. XXV, fig. B), in all three examples. Wall 



* That numbers of sea snakes fall victim to birds of prey, was 

 once demonstrated to me on visiting a large flat-topped buoy lying 

 some miles out to sea in the Bight of Bandon. The top of this 

 structure was covered with the dried bodies of snakes — chiefly 

 Enhijdris hnrcfyvickii — the birds having brought their victims 

 there, and i'.fter devourin,' the internal organs, left the remainder 

 to be disposed of by the elements. 



