CHAPTER II 



THE BUTTERFLY AND ITS ALLIES 



Systematic Position. Butterflies belong to the insect 

 order Lepidoptera, 1 characterized by the possession of a 

 long, coiled, sucking proboscis; large, membranous wings, 

 covered with colored scales; and a complete metamorphosis. 

 They occur over the whole globe, but become more numer- 

 ous in species in the tropics of South America and Africa. 

 The number of known species is about twenty-five 

 thousand. 2 



The Habits and Food of Butterflies. The idea of a 

 butterfly should not be limited to the winged adult called 

 the imago, for strictly we may call a caterpillar a larval 

 butterfly, and a pupa an adolescent butterfly. But in its 

 different stages the habits and food of a butterfly change. 

 Caterpillars feed, for the most part, upon plants. A few 

 such as the clothes-moth and certain enemies of scale in- 

 sects feed upon animal matter. Any single species of 

 caterpillar feeds upon the foliage of a restricted number of 

 kinds of plants. At one extreme we have forms which 

 starve unless they can reach their own particular food 

 plant; at the other extreme there are caterpillars which 

 can live upon the foliage of many kinds of plants, and 

 these are consequently called polyphagous. Certain fami- 



1 Xe7r/s, scale ; irrepbv, wing. 



2 The principal families of Lepidoptera may be distinguished by the 

 key in the Appendix to this Chapter, p. 41. 



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