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quiescent state, in vvhich the inject, except in a few orders, 

 lies quiet and has no power of motion ; (4) the perfect insect. 



Some are injuiious in all their stages, but the larger 

 number in only one, so that unless we know them in all 

 their stages, we lose opportunities for destroj'ing them by 

 not recognizing them as enemies. 



lujurious insects may be divided into two classes: (1) 

 those which possess jaws, by means of which they consume 

 their food ; (2) those which have instead a hollow tube by 

 which they suck up their food in the shape of liquid juice. 

 Now it is apparent that for insects of the first class, as the 

 potato bug, all that is necessary to do is to apply to the 

 foliage some poisonous material that will not injure the 

 plant, but which will destroy the insects while devouring the 

 leaves. For the second class, however, these »emedies are 

 u.seless, for they are able to pierce through the poisonous 

 material, and extract the juices upon which they live from 

 the interior of the leaf. With these insects it is necessary 

 to make use of such poisons as act by mere contact with 

 their bodies and do not require to be eaten. 



Then again, there is another class that may be termed 

 insect friends, as they prevent other species from doing 

 harm. In these man finds his greatest protection from the 

 countless hordes that rob him of so much of his produce. 

 They are known as Ichneumon flies and Tachina flies. 

 The forujer belong to the same order as the wasp and 

 the bee, and may be recognized by being very active, and 

 having two pairs of wings. The female lavs its eggs 

 beneath the skin of a caterpillar or soft-bodied insect, 

 l^hese hatch inside the victim and live upon the juices of its 

 body. When full grown it eats its way out through the skin. 



The Tachina flies have only one pair of wings. They 

 belong to the same order as the house fly, which they much 

 resemble. These lay their eggs on the outside of the skin 

 of the victim, and the young maggot eats its way into 

 its host. 



It is well that the farmer should know the appearance of 

 these insects, so that he may not destroy his friends as well 

 as his enemies. This is sometimes a diflficult matter ; but 

 as a general rule, if an insect is active and has well-devel- 

 oped running powers, it is harndess ; if slow and heavy in 

 its movements, it is probably injuiious. . . ; 



^ ''^ ' THE ROUND HEADED BORER " ^^ ,,,,,.■ 



is one of the most destructive insects with which we have 

 to contend. It is always worse in orchards that hav j not 



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