REPTILES. 201 



Rev. J. T. Lea, who dissected a large number of speci- 

 mens, found near his residence (Far Forest Vicarage), in 

 the Wyre Forest, the difference coincides with the sex ; 

 the grey ones being males, and the coppery ones females. 

 At a meeting of the Caradoc and Severn Valley Field 

 Club, held January i8th, 1897, Mr. Harold Peake, of 

 Ellesmere, sent for exhibition three very young Vipers 

 (taken near that town), each of which had two small 

 hind legs : these are believed to be unique, and are 

 highly interesting, since (according to the doctrine of 

 evolution), rudimentary organs found in the young, in- 

 dicate that the ancestral type possessed those organs in 

 a more perfect form ; that is to say, these rudimentary 

 legs indicate that the Viper has descended from ancestors 

 which possessed legs. This accords with the belief of 

 most modern biologists that snakes are descended from 

 lizards. The poison apparatus of the Viper is similar 

 to that of others of the venomous tribe of Snakes. It 

 consists of two poison fangs only, found in the upper 

 jaw, and these are very different from ordinary teeth. In 

 most poisonous snakes there are ordinary teeth in the 

 lower jaw, but none in the upper. The poison fangs, 

 unlike ordinary teeth, are hollow, and hinged at the base. 

 When not in use they each lie in a groove along the 

 upper jaw, with their points directed backwards, but at 

 the will of the animal they can be erected by a small 

 muscle, and then stand at right angles to the jaw, with 

 their points directed downward. When a Viper intends 

 to strike, it gathers itself together in a heap on the 

 ground, with the neck raised in the centre and the head 

 drawn back ; it then suddenly uncoils itself, like a spring, 

 throwing the body forward with extreme rapidity, though 



