ORDER IV. MOTHS AND BUTTERFLIES. 133 



colors, and even the plainest looking will appear handsome 

 upon a close examination with a magnifying glass. The 

 size of their bodies varies very much in proportion to the 

 size of the perfect insect, and their exterior surface is either 

 smooth, as that of the Asterias on the parsnep (Fig. 29), or 

 that of the Danaus on the milk-weed, or it is hairy like that 

 of the Saturnia (Fig. 26) on Indian corn and other grasses. 



The food of caterpillars, with a few exceptions, is taken 

 from the vegetable kingdom. Some feed exclusively on one 

 species of plant, as the silk- worm on the white mulberry ; 

 others on all the species of one genus, as the potato worm 

 on the tomato, potato, etc. ; others eat any kind of vege- 

 table, as the woolly-bear {Arctia). The periods of taking 

 their meals is also different ; some eat only in the morning 

 and evening ; others during the whole day ; and others only 

 at night, while they conceal themselves during the day, and 

 their depredations only are visible. But if by night we ex- 

 amine our cabbage, cauliflowers, and turnips with a lan- 

 tern, we shall often find them covered with a host of these 

 noxious individuals. 



Many of the caterpillars live like hermits, a solitary life, 

 and pay no attention to their brothers and sisters ; while, on 

 the contrary, many species are real socialists, and build in 

 common their comfortable silk dwellings, with which, if not 

 prevented by man, they sometimes cover entire trees. Here 

 they live, and feed together at regular hours ; as, for in- 

 stance, the Tent Caterpillar (Clisiocampo Americana, Har- 

 ris) on apple, pear, or cherry trees, and by such confrater- 

 nities the trees of an entire orchard are ruined, unless the 

 destructive intruders are destroyed in April or the begin- 

 ning of May. 



Single j^arts of Caterpillars. 



Head. — The head of a caterpillar is horny, of a globular 

 or oblong form : it contains a mouth with an upper and 



