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TWIG-WEEVILS. 



This is a class of snout beetles or so-called weevils which deposit 

 their eggs in the living, dying, and dead twigs of trees, and the larvae 

 mine in the bark and pith. When they infest the twigs of living trees 

 the}^ often do considerable damage. 



TWIG CATERPILLARS. 



These are the larvae of moths, which burrow into the terminal twigs 

 of pine and other conifers and often cause serious harm. There are 

 also certain kinds which attack the bark of the twigs and cause masses 

 of pitch to form, in which they live. 



SCALE INSECTS. 



This is an extensive class of insects which infest the bark of all sorts 

 of trees and are often very injurious. The young, after hatching 

 from the eggs or mother scales, crawl about and attach themselves to 

 the bark by means of their long, slender beaks. Many species exude 

 a kind of wax which forms a scale-like covering which protects them 

 during their period of growth. 



PLANT-LICE. 



These are similar to the plant-lice which infest the leaves, but cer- 

 tain kinds confine their attack to the twigs, especially some of those 

 belonging to the genus Lachnus. Some of them are covered with a 

 cottony or wool-like substance, while others are large, black, and 

 shining. 



GALL INSECTS. 



There are . many kinds of gall insects which produce galls on the 

 twigs of forest trees, and like those causing galls on the leaves 

 represent several orders and families. 



CICADAS. 



This is a class of insects of which the periodical cicada is a Common 

 example. They often cause serious injury to the twigs, which they 

 puncture for the purpose of depositing their eggs. 



INSECTS INJURIOUS TO FRUIT OR SEEDS. 



This designation refers to insects which attack the } 7 oung to matured 

 fruit and seeds on the living tree, or after they have fallen. 



WEEVILS. 



This is a class of snout-beetles which are often very injurious to 

 acorns and various kinds of nuts. The eggs are deposited in the young 

 fruit and the young larvae live on the inner portion until the nut or 

 fruit has matured and falls to the ground, when they burrow their way 

 out and go into the ground to transform to adults, which come out 

 the next year in time to repeat the operation. 



