Chapter V 

 INSECTS AND THEIR SURROUNDINGS 



Ye insects small, to which one leaf 



Within its narrow sides 

 A vast extended world displays 



And spacious realms provides. — Skelton. 



Abundance of Insect-Life. — Hitherto we have 

 considered Insects mainly with regard to the form 

 and structure of their parts, and the process of 

 growth by which these parts have been developed. 

 In discussing the uses of the various organs it has 

 been necessary to touch upon the relations of the 

 individual insect with the outside world. With a 

 general knowledge of the structure, life-history, and 

 classification of insects, we can now pursue this 

 subject more fully, and study some of the chief 

 points of correspondence between living insects and 

 their surroundings,^ 



A fact early forced on the attention of the 

 observer of living insects is their abundance. If 

 in our countries we cannot make acquaintance with 

 the hordes of ants and swarms of locusts described by 

 travellers in the tropics, we are soon led to see 

 that, both in the number of individuals and of 

 kinds, insects exceed all other animals. This fact 

 can be brought home by the zoological exploration 

 of an ordinary dwelling-house. A number of animals 



1 This special study of living animals in relation to their sur- 

 roundings is distinguished by naturalists as " bionomics," 



