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ELEMENTARY STUDIES IN INSECT LIFE 



similar to the parent ; what they feed upon and the 

 time when they mature ; how their food is procured, 

 whether !>y grasping and chewing with jaws, or by 

 sucking through a beak. These things he can learn from 

 books, but he can learn them far better, just as he has 

 gained his best knowledge in horticulture, by the vigilant 

 use of his eyes while following his chosen profession. 

 If the insect, eats the leaves, as caterpillars do, the 

 successful horticulturist knows that this insect can be 

 reached by poisonous sprays thrown upon the leaves. 

 If the insect procures its fond by inserting its beak into 

 the leaf, the fruit-grower will readily understand that 

 a poisonous spray will not kill this insect, since it does 

 not eat the leaf spread with Paris green, but pushes its 

 beak down through the poison into the leaf and with- 

 draws its sustenance unharmed. 



One of the earliest instances of successfully combat- 

 ting an insect took place in Sweden. In the time of 

 Linnaeus the Swedish ship-builders were seriously both- 

 ered by a borer destroying the ship timbers in their 

 yards. They applied to Linnaeus for assistance. This 

 noted naturalist, after Diving the subject of the life 

 history of the insect careful study, told the ship- 

 builders that if they would submerge the timbers in 

 the sea during the month of May they would have no 

 further trouble from the pest. The naturalist had found 

 that these borers were the larva 1 or grubs of a beetle 

 which lays eggs upon the wood only in the month of 

 ~Mi\\. lie readily perceived that if this wood could be 

 placed where the beetles could not find it during this 

 month they would be compelled to deposit their eggs 

 elsewhere. Then when the eggs hatched, the young 



