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other beneficial. In cultivating plants for fruit, as in all other 

 lines of cultivation, we are trespassing certain laws of nature, and 

 the increase of the plant feeding species of insects is one of the 

 difficulties resulting therefrom. To off-set this disturbance, the 

 fruit grower must be prepared to protect his trees from the 

 ravages of insect enemies, or wage war against them if they have 

 already gained a foothold in the orchard. To do this intelligently 

 and with economy of time and expense, something must be known 

 of insects in general and the insects injurious to fruits in particu- 

 lar, 



WHAT AN INSECT IS. 



The terms "insect" and "bug" are commonly applied to all 

 minute organisms or anything that crawls ; properly, an insect 

 is a member of a certain class of lower animals, while a *'bug" is a 

 member of a certain order of insects. The term ''blight" is in- 

 correct, it being the common name of the fungus diseases of 

 plants, themselves low parasitic forms of plant life. Insects con- 

 stitute the class Hexopoda or Insecta, and the derivation of the 

 former Greek word gives the chief distinctive characteristic of 

 insects, that is, they possess six feet. Insects are, zoologically, 

 closely related to spiders, scorpions and centipedes, lower forms 

 of invertebrate animals, but further distinguished from them by 

 having the body segments divided into three well defined parts, 

 and supplied with certain appendages. 



STRUCTURE OF INSECTS. 



The body of an insect is made of a series of segments or "body 

 rings" divided into the head, the thorax and the abdomen. The 

 first two divisions of the body bear certain appendages char- 

 acteristic of all insects, namely the antennae or "feelers" and the 

 mouth-parts of the head, and the legs and wings of the thorax ; 

 there being always in the adult insect three pairs of legs and 

 usually one or two pairs of wings. The segmentation of an in- 

 sect is well shown in the abdomen, not so clearly indicated in the 

 thorax, and in the head fusion has progressed to such an extent 

 that this part of the body appears as a box-like structure. The 

 skeleton is external, that is, the internal organs of digestion, the 

 nervous system and the repiratory system, as well as the muscles 

 of the body-wall, are supported and protected by a hard shell-like 

 covering. This covering or chitin is so deposited in certain places 



