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CHAPTER VIII

INSECTS


The Grasshopper


Suggestions.—Collect grasshoppers, both young and full-grown, and keep alive in broad bottles or tumblers and feed on fresh grass or lettuce. When handling a live grasshopper, never hold it by its legs, as the joints are weak. To keep them for some time and observe their molts, place sod in the bottom of a box and cover the box with mosquito netting or wire gauze.


What is the general shape of its body? (Fig. 106.) Where is the body thickest? Is it bilaterally symmetrical, that is, are the two sides of the body alike? Is the skeleton, or hard part of the body, internal or external? Is the skeleton as stiff and thick as that of a crawfish? What is the length of your specimen? Its color? Why does it have this coloration? In what ways does the grasshopper resemble the crawfish? Differ from it?

Fig. 106.—A Grasshopper.

The Three Regions of the Body.—The body of the grasshopper is divided into three regions,—the head, thorax, and abdomen. Which of these three divisions has no distinct subdivisions? The body of the grasshopper, like that of the earthworm, is made of ringlike segments. Are the segments most distinct in the head, thorax, or abdomen? Which region is longest? Shortest? Strongest? Why? Which region bears the chief sense organs? The appendages for taking food? The locomotory appendages? Which division of the body is most active in breathing?