CHAPTER XI 



CLASSIFICATION IN GENERAL AND OF INSECTS IN 

 PARTICULAR 



WHEN one has a large number of different kinds of objects be- 

 fore him, it is but natural for him to try to arrange them in some 

 orderly fashion. If a person unacquainted with insects were 

 given several hundred of them, he would have little difficulty 

 in separating them into groups of butterflies, beetles, flies, etc., 

 which would, at least approximately, coincide with the groups 

 in which these insects are placed by scientists. What such a 

 person does is to pick out some characteristic that seems to be 

 general, such as the large, beautifully colored wings of the butter- 

 fly or the hard, sheathlike wings of the beetle. 



Artificial Classification. A study of the habitats of insects has 

 shown that (i) some live on the surface of the ground ; (2) some 

 burrow in the ground; (3) some live in the waters of ponds 

 and streams; (4) some fly about in the air much of the time; 

 (5) and many live on or in the bodies of other animals. We can 

 classify these insects according to their habitats as terrestrial, 

 sub terrestrial, aquatic, aerial, and parasitic, but a group col- 

 lected from any one habitat will exhibit among themselves a 

 great diversity in characteristics. This sort of classification is 

 called artificial. 



Natural Classification. A natural classification attempts to 

 place every animal in its proper place according to its kinship 

 with other kinds of animals. The grouping of insects employed 

 in the preceding chapters is artificial since, for example, under the 

 heading of insects of the household we mentioned among others 



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