16 



Head shields — The nasals are contiguous, there being no 

 internasals. The supra- and post-oculars are 

 confluent. No temporals. Upper labials 

 four. 



locales — 17, round and polished. 



FeniraZ.s — 193 to234. Very narrow. Sub-caudals 6— 1 1. 



Colour — Yellowish ; or brown above usually with numer- 

 ous transverse series of small, yellow black- 

 edged ocelli. Belly brown with large yellow 

 spots or cross-bands ; or yellow mottled or 

 blotched. , 



Habitat — These small burrowing snakes are fairly com- 

 mon in the hills of Southern India at a height 

 from 2,000 to 4,500 feet. 



RUSSELL'S WATER SNAKE {Cerberus rhynchops). 



This snake is about the commonest and most typical 

 of the river snakes. 



The river snakes live in rivers and estuaries and rarely 

 come to land. 



Length— Grows to 3 feet or more. Tail one-fifth of 

 length. 



Shape — Head : small, not very distinct from neck. Cleft 

 of mouth turned up behind the eye. 



Body : cylindrical. 



Tail : moderate, slightly compressed. 



Eye : small, pupil vertically elliptic. 



Nostrils small, placed on the top of the head 



and valvular. 'This feature is characteristic 



of the river snakes. 



Head shields — The head is shielded but irregularly (as 

 in all the river snakes)., 

 The frontal may be broken up into small shields. 



