92 SNAKES OF CEYLON. 



History. — First referred to and figured by Russell in 1796 

 (Vol. I., Plates XX., XXVIII., XXXIII., and Vol. II., Plates 

 III., XIV., and XV.). Christened by Schneider in 1799. 



General Characters. — A moderate -sized species growing to 

 over 3 feet in length. Head ovate, and snout subacute, 

 with an indistinct obtusely rounded canthus. Neck fairly 

 evident. Eye with a decided inclination upwards, an iris 

 speckled with greenish -gold, and a round pupil. Nostril 

 slit-like, and placed unusually high on the snout, thus 

 approximating to the condition seen in the true fresh-water 

 snakes of the Sub -family Homalopsinse. Body stout and 

 muscular ; cylindrical ; attenuating slightly towards the 

 neck and posteriorly, and rough from the keeling of 

 the costals. Belly rounded. Tail longish, being more than 

 one-fourth, and approaching one -third the total length. 



Identification. — The costals 19 two heads -lengths behind 

 the head, 19 at midbody, and 17 two heads-lengths before 

 the vent, and the rostro-internasal sutures half or less than 

 half the rostro -nasals will serve to identify this among Ceylon 

 snakes. 



Colouration. — A variable snake. In Ceylon there are at 

 least three varieties. 



(a) "Variety flavipunctata (Gunther) : Olive -brown or 

 olive -green dorsally, with one or more lateral series of pale 

 spots. 



(b) Variety quincunciata (Schlegel) : Olive-brown or olive- 

 green dorsally, with six series of black spots forming a 

 chequered pattern. These spots are more pronounced 

 anteriorly. 



(c) Variety asperrima (Boulenger) : Like the last 

 posteriorly, but with a single series of very large lateral 

 black blotches anteriorly, those of one side more or less 

 confluent with those of the other. 



In all the head is olive -brown or olive -green, with two 

 narrow, black, oblique streaks from the eye, the upper longer, 

 passing across the front of the gape, and the lower to the lip 

 on the 5th and 6th supralabial shields. Belly pearly-white, 

 sometimes with a pinkish suffusion laterally. Young are 

 marked like adults, except that they have a small light dot 



