INSECTS AND THEIR CONTROL 245 



EXERCISE IV. Study other insects common in your locality, follow- 

 ing the above methods. 



Make studies of the egg, larva, pupa, and adult stages wherever 

 possible. 



EXERCISE V. Study of insecticides. 



Materials. As many insecticides as possible; glass jars or glass 

 cylinders; water. 



Procedure. Study each material as to the following: Form, whether 

 solid or liquid; color, fineness, solubility in water, precipitation. 



EXERCISE VI. Test for inert material in paris green. 



Materials. Samples of paris green, strong ammonia, test-tubes. 



Procedure. Dissolve a small amount of paris green in a test-tube 

 half filled with strong ammonia. The paris green dissolves but inert 

 material remains in the form of a precipitate. 



