OUTLINE OF CHAPTER XII. 



ENEMIES OF PLANTS. 



y^.— INJURIOUS INSECTS. 



I. General Characters of Insects. 

 II. Metamorphosis. 



III. Apparatus Needed in Collectinc" .-^r J Rcarin? 

 Insects. 



1. Net. 



2. Cyanide />oftle. 



3 . Byecding -J a rs. 



IV. Field Trip. 



V. Laboratory Studies. 



1 . Stitdy of the Live Insect. 



2. Grasshopper. 



3. Nymph. 



4. Butterfly, or M'th. 



5. Caterpillar. 



VI. Economic Classification of Insects. 



1. Group I.— With Bitini:: Mouth- parts. 



2. Grcup If. — IVith Sucking Mouth-parts. 



VII. Preventives. 



1 . Removal of Debris. 



2. Change of Crops. 



VIII. Insecticides. 



1. Group I. — Poisonous Insecticides. 



2. Group II. — Contact Insecticides. 



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