268 SNAKES OF CEYLON. 



Identification. — The compressed body, narrow neck, large 

 eye with vertical pupil, the enlarged vertebral row of 

 scales, and the entire anal shield (with rare exceptions, 

 none of which are Ceylonese) constitute a syndrome, 

 by which the representatives of the genus are easily 

 recognized. 



Habits. — Arboreal. Nocturnal. Active. Fierce, when 

 provoked. 



Food. — Small mammals, birds, lizards, batrachians. 



Breeding. — Oviparous so far as is known. 



Poison. — Feebly poisonous, producing at the worst some 

 trifling local effects. 



Lepidosis (for Indian species). — Rostral : Touches six 

 shields. Internasals : A pair. Prefrontals : A pair. Fron- 

 tal : Touching six shields. Nasals : Divided. Loreal : 

 Present, shorter than the nasals. Prseoculars : One to three. 

 Postoculars : Two. Temporals : Two or three ; small, 

 scale like. Supralabials : Eight to ten ; three touching the 

 eye. Sublinguals : Two pairs ; subequal, or the posterior 

 rather shorter. Infralabials : The last about as broad 

 as the posterior sublinguals, but shorter than those 

 shields. 



Costals : Longer than broad ; smooth or feebly keeled ; with 

 apical facets. Vertebrals : Enlarged, rectiform ; originating 

 on the nape by a confluence of three rows, terminating in 

 the supra-anal region. Last three rows rectiform, progres- 

 sively increasing in breadth. The rows between the third 

 and the vertebral oblique, and their breadth about half 

 their length. Ultimate row broadest. In 13 to 31 rows at 

 midbody. Ventrals : Rounded. Anal : Entire or divided. 

 Supracaudals : In even rows ; vertebrals not enlarged. Sub- 

 caudals : Divided. 



Dentition. — Maxillary : Opisthoglyphous, diacranterian. 

 Praecranterian : Feebly kumatodont. Cranterian ; Two or 

 three ; enlarged ; grooved on their anterior faces ; obliquely 



