1 70 THE RIVER-SIDE NATURALIST. 



in the hot weather, when probably the virulence of the 

 poison is more effective. The viper is ovo- viviparous, thus 



differing from the common snake, 

 and produces as many as from 

 twelve to twenty young ones 

 at each birth. It hibernates in 

 the winter months. The general 

 colour varies considerably in 

 some olive or a rich brown, in 

 others a dirty yellow-brown, in 

 others again extremely dark, 

 FIG - * almost black. This variation of 



colour has led some to suppose that there were different 

 species, but this is not the case. Adders vary much 

 in length, but any over 24 inches must be considered as 

 great rarities. The best remedy for the bite is ammonia, 

 employed both externally and taken internally. The common 

 form of sal volatile will do. A mark between the eyes, a 

 spot on each side of the hinder part of the head, and a 

 zigzag line running the whole length of the body and tail, 

 as well as a row of small triangular spots on each side, 

 all of a much darker colour than the ground of the body, 

 easily distinguishes the viper from the RINGED or COMMON 

 SNAKE, Fig. 2 (Natrix torquata; family, Colubridce), which 

 is plentifully distributed over all 

 parts of England. It swims with 

 ease and rapidity, and we have 

 often seen this snake cross a river ; 

 its fondness for frogs as food may 

 account for its resorting to moist 

 places and streams. This snake 

 is oviparous, and generally deposits 

 its eggs either in a hotbed of leaves 

 FIG. 2. or in dunghills. It hibernates in 



winter. The upper parts of the body and head are of a 

 light brownish-grey, with a green or olive tinge. Behind 

 the head is a broad band of yellow, and close behind two 

 broad spots of black. Two rows of small black spots are 

 arranged alternately down the back, and larger ones at 



