REPTILES 



233 



by the markings on its upper side, consisting of a dark blotch 

 on the neck and a double series of brown spots running down 

 the body. It feeds on other reptiles. 



Both these British species, especially the Grass Snake, have 

 a wide distribution outside of Great Britain. 



Fig. 146 

 I. Grass Snake {Tropidonottts natnx). z. Smooth Snake [CoroTtella Itzvis). 3. Adder {Pelias herus). 



2. Whip-Snakes and their allies are green tree-inhabiting 

 forms, native to the tropical regions of Asia, Africa, and America. 

 The head is small and pointed, the body extremely slender. But 

 the most remarkable peculiarity is seen in a varying number of 

 the hinder teeth of the upper jaw, each of which has a groove 

 in front. Such grooves on the upper teeth of serpents generally 



