52 BRITISH SERPENTS. 



confinement occasionally devoured spiders, but blue- 

 bottle flies whenever given ; so finding that the snakes 

 throve on this diet, we did not try them with other 

 kinds of food. Mice, slow-worms, and the viviparous 

 lizard are comparatively scarce on our heaths ; its food, 

 therefore, with us probably is for the most part the 

 sand-lizard. 



"A correspondent ('Zool.,' 9559) states that Cor- 

 onella Icevis emits a strong odour for defence ; but 

 Dr Blackmore (' Zool.,' 9735) says it emits no smell 

 at all, even when irritated. I myself have never 

 noticed any odour in either of the examples I have 

 obtained, so I conclude that if it does emit an odour 

 it is of rare occurrence. Opel states ('Zool.,' 9511) 

 that its colour after sloughing is a beautiful steel 

 blue for six or seven days. Each of the two we had 

 in confinement changed its skin, but the only differ- 

 ence I noticed was that they were of somewhat 

 brighter and clearer hue than before. In one of 

 the examples the spots and markings were scarcely 

 visible until after the change of skin. This snake 

 is of a bold and fearless nature ; one of those I 

 captured (having come upon it suddenly) reared itself 

 erect on its tail to its full height, hissing and darting 

 out its forked tongue in a very pugnacious way. It 

 certainly seems to me to be much more frequent on 

 our heaths than it was when I first discovered it 

 there ; and I often hear of its being seen by others. 

 Its usual habitat is, no doubt, dry sandy spots, but I 



