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How Insects Breathe. 



The familiar grasshoppers, or locusts as they are better called, 

 can be found along roadsides, and in pastures and meadows. 

 Have some energetic and interested small boy catch alive and 

 bring to the school as many live locusts as there are children in 

 the nature study class. Any species of locust will do, the speci- 

 mens need not all be of the same species even. The locust hunter 

 should carry a small closed wooden or paste-board box with a 

 hole in the top just large enough to admit a single locust. If he 

 can take with him a butterfly net he may be able to get his speci- 

 mens in shorter time, tho the usual small boy can catch the most 

 active sort of locust without artificial equipment. 



Let each child of the class have a live locust. It should be 

 held so that the long, strong hind legs are kept quiet. When the 

 locust has stopped struggling to free itself and is apparently 

 motionless, let all look sharply for any signs of movement. Give 

 especial attention to the hinder half of the body. 



Is there any movement here ? Yes, a distinct tho slight, 

 regularly-recurring contracting and swelling of the body. What 

 is the locust doing ? Breathing. Notice this movement of the 

 body very carefully in all its details. What parts of the body 

 surface move the most ? Of what is this part of the locust's body 

 composed ? Of a series of rings or segments with distinct lines 

 separating them. Note that the under surface of the body is 

 separated from the lateral and upper parts of the body by a little 

 longitudinal furrow on each side. It is at these furrows that the 

 breathing motion is most pronounced. Feel the surface of the 

 body; it is rather hard. The outer skin, or surface of the grass- 

 hopper's body is composed of a thin layer of a horny substance 

 which serves as a sort of coat of armor and protects the soft parts 

 inside. But just at the furrows the body wall is thin and soft. 



