1847.] Malayan Peninsula and Islands. 1049 



abdominal scales are hexagonal, with or without a small tubercle on 

 each side. The anus is covered by three or four excessively large 

 scales. The larger individual of two was of the following dimensions : 



Length of the head, ft. If inch. 



Ditto ditto trunk, 5 6f 



Ditto ditto tail, 4f 



6 ft. Of inch. 

 Circumference of the neck, 3f, greatest do. of the trunk, 4f inch. 



Hydrus nigrocinctus, (Daudin.) 



Syn.*— Russell, II. PI. 6. Kerril Pattee, 1801. 

 Hydro phis nigrocinctus, Daudin, 1803. 

 Hydrophis melanurus, Wagler, 1828. 

 Polyodontes annulatus, Lesson, 1833. 

 Hydrophis nigrocincta, Schlegel, 1837. 

 Hydrophis nigrocincta, Schlegel, apud Cantor, 1. c. 



New horn. — Ground colour buff or bluish-white ; upper-lips and 

 muzzle black, and a transversal band across the hind head, from whence 

 proceeds a triangular or cross mark towards the vertex ; gular and 

 inferior labial shields edged and spotted with black ; trunk and tail with 

 numerous black transversal bands, either encircling the body, or inter- 

 rupted on the abdominal ridge, where appear a few indistinct black 

 spots ; apex of the tail black. Entire length 8f inch. 



Older. — Greyish green olive above, yellowish on the sides, buff be- 

 neath ; the bands less intense black, often placed obliquely so as to 

 join each other on the back. Iris grey ; pupil circular, black ; tongue 

 buff. Central abdominal series of larger scales, 281-f- 41 ; 284 4- 43 ; 

 289+ 39. 



Habit. — Sea of Malayan Peninsula, Pinang, Singapore. 

 Estuaries of the Ganges, Bay of Bengal. 



This species greatly resembles H. striatus, from which it differs in 

 the more compressed general form ; the eye though small, is of a larger 

 diameter than the nostril, and it is surrounded by a single post-orbital 

 shield, which beneath is wedged in between the fourth and fifth upper 

 labial, and the prse-orbital between the second and third. The orbit is 

 bordered beneath almost entirely by the fourth upper labial. The 



* Doubtful Syn.— Russell, II. PL 13, Kaddell Nagam, 1801. (Enhydris gracilis, 

 Merrem, 1820.) Hydrus spiralis, Shaw, 1802. 



