THE ADDER. 113 



conditions can hardly be so diverse as to influence the 

 colours of animals. Hot climates are often associated 

 with brilliant colouring; but this is a matter of pro- 

 tective resemblance, and not the point under discus- 

 sion. Even if it were shown that adders in one comity 

 differed from those in another, climate in this country 

 could not be held responsible for that difference. 



3. Food. — A striking resemblance is seen in some of 

 the lower animals between the creature and its food, 

 in the matter of colour, especially in insects ; but 

 this, again, is protective colouration. There is no 

 evidence that I am aware of to indicate that the 

 food of British adders has any connection with their 

 varying colours. 



4. Locality. — Locality in this connection means the 

 exact nature of the soil and vegetation in a given area. 

 This at first sight seems to afford the explanation 

 sought for; and it should be stated at once that the 

 theory that adders vary in colour according to the 

 place they haunt is the one generally accepted. 

 Personally, I do not believe it to be true, and shall 

 attempt to give good reasons for that disbelief. It 

 comes to this, if the varying colours of adders are due 

 to the locality they haunt, then there is found in a 

 single species an immense variety of instances of pro- 

 tective colouration within a very limited area. Still, 

 it is very natural to suppose that adders vary accord- 

 ing to their surroundings. The adder whose habitat 

 is light sandy soil easily answers to the coppery -red or 



H 



