CHAPTER VII. 
VIPERA BERUS, OR ADDER. 
DISTRIBUTION — DESCRIPTION — AVERAGE SIZE—MARKINGS AND 
COLOURS—HAUNTS 
FOOD, 
WE now come to the consideration of our. sole 
venomous serpent in these islands— Vipera berus, the 
adder, or, as it is often called, the viper. It has 
been explained in chap. i. of this book why this 
species will he discussed somewhat more fully than 
was the case in the two serpents already considered. 
Distribution.— Vipera berus is distributed over 
almost the whole of the European continent, the 
extreme north exeepted, where the cold is too in- 
tense for serpents to flourish. In Scotland it is 
much more common than the ring snake, while in 
England its distribution is very various, and will be 
found under the head of the separate counties, in a 
later chapter. In Wales it is very common in some 
places, rare in others. Like the other ophidians, it 
