COMMON VIPER. 65 



from it ; the poison eitlier does not exist at all, or it is 

 inert. 



It frequents dry sandy heaths and waste places, not re- 

 quiring, like the Snake, the neighbourhood of water, nor 

 swimming so readily as that species. In many parts of the 

 country it is even more common than the Snake. 



The name Adder, by which it is known in many parts of 

 England and Scotland, is anciently written nedre, and after- 

 wards eddre, the initial 7i being dropped. It is from the 

 Anglo Saxon yiadre, — nether, lower, — from its creeping po- 

 sition, and the name was applied to all the Serpent tribe. 

 The word Viper, Latin Vi'pera, is derived from its viviparous 

 habit. 



The head is somewhat depressed, almost oval, slightly 

 widening behind the eyes. Gape as long as the head, as- 

 cending behind. No teeth in the upper maxillary bones, 

 excepting the poison-fangs ; a row of small teeth in the pala- 

 tine bone on each side. Neck rather smaller than the back of 

 the head, from which the body increases to nearly the middle 

 of the entire length ; the rest of the body to the vent scarcely 

 diminishing ; the tail becoming almost abruptly smaller, and 

 tapering to its extremity, which is pointed ; the tail varies in 

 its proportion to the body, but is generally not more than 

 one-eighth of the total length, and in some even less. The 

 head is covered with small squamous plates, which in some 



