ARTHROPOD A 187 



important pests. The cotton-boll worm and the cotton worm cause 

 millions of dollars loss annually to the cotton growers. The 

 Bombycidae include the coinmon silk-worm moth. The silk worm has 

 been artificially bred in China for over five thousand years. 



Some of the largest and most showy of the moths belong to the 

 giant silk worm family, the Saturniidae. These include the Poly- 

 phemus, the Cecropia, and the Luna moths. The Cecropias are a 

 trifle injurious to shade trees, but in general these species are 

 interesting only on account of their size. The carpenter moths 

 (Cossidae) are wood-borers attacking trees. 



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Fig. 86. yf, clothes moth. 5, larva of clothes moth. (After Riley. U. S. Dept. Agr.) 



The Geometridae are called " measuring worms " when in the 

 larval state. An extremely important species is the spring canker 

 worm (Paleacrita vernata) whose larvae feed on the leaves of fruit 

 trees. The Liparidae or tussock moths injure shade trees. The 

 white marked tussock moth is a native form injurious to fruit and 

 shade trees, while the antique or rusty tussock moth is a European 

 species found in Nova Scotia, New England and the West. The 

 brown tail moth attacks shade and forest trees, but avoids the 

 conifers. The gypsy moth has spread from the New England states 

 into some of the Middle Atlantic states. The Sphingidae include 

 the hawk moths or humming bird moths. They have long tongues 

 adapted for sucking nectar from flowers like honeysuckles. The 

 butterflies have their antennae enlarged at the tips, and fly exclu- 

 sively in the daytime^ while moths fly at night and have threadlike 

 or feathery antennae. There are two great super-families, the 

 Papilionina or true butterflies and the Hesperina or skippers. 



The Nymphalidae include forms with poorly developed front 

 legs, not adapted to walking. Some of the more common forms are 

 the thistle butterfly, the Admiral, the wood nymph and the viceroy. 

 The viceroy is interesting because it closely resembles the bad tasting 



