SNAKES OF CEYLON. 197 



Dentition . — Maxillary : 12 to 24 ; syncranterian, anododont, 

 isodont, or scaphiodont. Palatine : 9 to 13 ; anododont, 

 isodont, or scaphiodont. Pterygoid: 12 to 27; anododont, 

 scaphiodont. Mandibular : 21 to 31 ; anododont, scaphiodont. 



Distribution. — Europe, Asia, North and Tropical America. 



When Boulenger's Catalogue appeared in 1894 forty -five 

 species were recognized. Of these, one occurs in Ceylon, viz., 

 Helena. 



CoLtTBEE HELENA Daudin. 



(Named on account of its beauty after Helen, the wife 

 of the Spartan King Menelaus.) 



Davdin's Coluber (or The Trinket Snake). 



Sinhalese : " mudu karawala " (Willey). Tamil : " kattu 

 pambu " (banded snake). 



Synonymy. — Herpetodryas helena, H. malabaricus, Gynophis 

 bistrigatus, G. malabarica, G. helena, Plagiodon helena. 



History, — Russell first referred to the species in 1796, and 

 gave a good illustration of it in Plate XXXII. of his first 

 volume. Christened by Daudin in 1803. 



General Characters. — ^Head rather narrow, with a somewhat 

 elongate and bluntly-rounded snout. There is little or no 

 indication of acanthus. Nostril fairly large, occupying about 

 three-fourths of the upper part of the suture between the nasal 

 shields. Eye moderately large, rather less than half the 

 length of the snout, and placed laterally. Pupil round, or 

 horizontally elliptical , and the iris adorned with gold. Tongue 

 pinkish at the base, becoming bluish-black, except at the Very 

 tips, which are white. I noted in a specimen from the Nilgiris 

 that the mucous membrane of the mouth was blackish. Neck 

 fairly evident. Body robust, compressed somewhat, and 

 smooth. Bellyangulated obtusely on either side. Tail short 

 and about one-fifth the total length of the snake. 



