SNAKES OF OBYLON. 231 



The genus comprises about forty species, four of which 

 occur in Ceylon, viz., arnensis, tasniolatus templetoni, and 

 sublineattis. 



Oligodon arnensis (Shaw).* 



(Latin, denoting an inhabitant of Arni in South India, 

 where the type specimen was found.) 



The Common Kukri Snake,. 



Synonymy. — Coluber arnensis, C. russelius, C. monticolu^s, 

 Coronella russeli, Simotes russellii, 8. albiventer, S. arnensis. 



History. — ^It was first figured by Seba in 1735. (Thesaurus 

 II., Plate LXII., Fig. 4.) In 1796 Russell figured it twice 

 in his first volume (Plates XXXV. and XXXVIII.). 



General Characters. — As detailed under the genus. A neck 

 is fairly evident. The tail is about one-seventh the total 

 length. 



Identification. — ^The costals 17 two heads-lengths behind 

 the head, 17 at midbody, 15 two heads-lengths before vent, 

 and the supralabials seven, with the 3rd and 4th only touching 

 the eye, will distinguish this from other Ceylon snakes. 



Colouration. — The ground colour is brown of various hues, 

 incUned sometimes to a ruddy or a purplish tint. It fades 

 to a more or less degree in the flanks. The back is crossed 

 with black bars which are narrowly, but usually distinctly, 

 outlined with whitish or pale yellow. They do not reach 



* This snake has since 1854 been included in the genus Simotes- 

 The genus, however, was separated from Oligodon by Dumeril and 

 Bibron on the erroneous observation that the species of Oligodon had 

 no teeth in the palate. Later, Boulenger, while admitting that some 

 species had palatine teeth, retained the genus on the erroneous obser- 

 vation that species of Oligodonhad no pterygoid teeth. All the species, 

 included in the two genera that I have been able to obtain skulls of, 

 have pterygoid teeth, except templetoni, so that the grormds fo^ sepa- 

 rating the two are without foundation. All should, therefore, be 

 included in a single genus, and for this Oligodon has priority, dating 

 as it does from 1827. 



