CHAPTER III 



SOME INSECT ADAPTATIONS 



Our knowledge of the activities of the grasshopper and the 

 structure of this insect will enable us to understand the modi- 

 fications that serve to adapt other insects to their various modes 

 of life. The number of these adaptations is legion and we shall 

 therefore have to select a few of the most interesting ones that 

 can be observed in the laboratory. 



Fro. p. — A, a back-swimmer. Notice the oar-like hind legs. (After Weed.) 



B, a mole-cricket with front legs fitted for digging. (After Barret.) 



C, young of the Cicada with front legs fitted for digging. (After Marlatt 

 and Riley.) 



Locomotion. — First, as regards locomotion, we may refer to 

 the insects that spend their lives in the water or underground. 

 Many aquatic insects are excellent swimmers, with legs specially 

 constructed for use as oars. This is true of the whirligig 



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