366 OPHIDIA. 



neck. Scales but very little imbricate, strongly keeled, the keel of each scale having two 

 tubercular prominences ; the scales on the posterior half of the body are as high as long, and 

 subtruncated behind. Ventral shields 340 in number, twice as broad as the scales of the 

 adjoining series, and each with several minute tubercles on each side. Terminal scale of the 

 tail of moderate size. Dirty yellowish : trunk with forty-seven large rhombic black cross 

 bands, broadest and nearly touching one another on the back, tapering and faint on the 

 sides. Upper side of the head uniform blackish in the adult. 



The typical specimen is the only example I have seen of this species ; it is said to be 

 from Singapore, and 43 inches long, the tail measuring 4^ inches. It is a male, and has a 

 thick tail. 



Hydrophis spiralis. (Plate XXV. fig. D.) 



?? Shiddil, Russell, Ind. Serp. ii. tab. 12. 

 Hydrus spiralisj Shaiv, Zool. iii. p. 564. tab. 125. 

 Hydrophis melaniirus, Wagl. Ic. Ainjjh. tab. 3. 

 ■ • spiralis. Gray, Viper. Snakes, p. 54. 



Head of moderate size and width ; neck and body somewhat elongate. The thii'd and 

 fourth labial shields enter the orbit ; one postocular ; three temporal shields on the side of 

 each occipital, the anterior being the largest. Two pairs of chm-shields, which are in contact 

 with one another. Twenty-nine to thirty-three series of scales round the neck. Scales im- 

 bricate, each with a central tubercle, those on the posterior half of the trunk as high as long, 

 and rounded behind. Ventral shields 320 in number, twice or thrice as large as the scales 

 of the adjoining series, nearly all being undivided. Prseanal shields of moderate size. Trunk 

 surrounded by from forty-two to forty-eight black rings, which are scarcely broader on the 

 back than on the sides and belly, and about half as broad as the interspaces of the ground- 

 colour. A series of round black spots alternating with the black rings, along the vertebral 

 line ; this series commences either before, or on, or behind the middle of the length of the 

 animal. Head black above, with a horseshoe-shaped yellow mark, the convexity of which 

 rests on the frontal shields ; the lower half of the upper lip, the chin, and throat yellowish ; 

 belly black, at least along its anterior half; posterior part of the tail black. 



I have examined seven specimens of this species, which has been confounded with other 

 sea-snakes by Schlegel and Fischer. Five of them, including the typical specimen, are 

 young, showing an open umbilical aperture, and 15 inches long ; the others are adult, one 

 being 6 feet long. They are from the Indian Ocean, but the localities where they were 

 captured ai'e not mentioned. It is extremely doubtful whether Russell's Sldddil is identical 

 with this species; it differs not only in coloration, but it appears to be also of a much 

 stouter habit. 



We have given three ^dews of the head, and one of a portion of the body, to show the 

 coloration. These figures are taken from a young specimen, and are of the natural size. 



