OUTLINE OF CHAPTER XII. 



ENEMIES OF PLANTS. 



^.INJURIOUS INSECTS. 



I. General Characters of Insects. 

 II. Metamorphosis. 

 HI. Apparatus Needed in Collecting ^rd Rearing 



Insects. 



1. Net. 



2. Cyanide Bottle. 



3. Breeding-jars. 



IV. Field Trip. 



V. Laboratory Studies. 



i . Study of the Live Insect. 



2. Grasshopper. 



3. Nymph. 



4. Butterfly, or Moth. 



5. Caterpillar. 



VI. Economic Classification of Insects. 



1. Group I. With Biting Mouth-parts. 



2. Group II. With Sucking Mouth-parts. 



VII. Preventives. 



1. Re moral of De'bris. 



2. Change of Crops. 



VIII. Insecticides. 



1. Group I. Poisonous Insecticides. 



2. Group II. Contact Insecticides. 



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