THE MICROSCOPE AND INSECT LIFE 



More easily found insects, in this country, at any 

 rate, are the cricket and the grasshopper. The 

 cricket we all know is a persistent songster. Let 

 us examine him closely. We shall find, that the 

 house cricket has two pairs of wings ; the fore wings 

 are leathery, the hind wings membranous. If we 

 watch a male in the act of chirping, the male 

 crickets like the male Cicadas are the songsters, we 

 shall observe that he moves his wings slightly. If 

 now we examine a dead male, we shall find, on the 

 under surface of the fore wing, a rough patch. Let 

 us examine this patch under the microscope, it re- 

 minds us of nothing so much as a file : it is a file 

 in fact, and sound is produced by rubbing this rough 

 file against a ridge, which we can easily see, on the 

 upper surface of the hind wing. 



It would be a useless accomplishment for the 

 cricket to be able to sing, if there were no ears to 

 hear its song. Nature has arranged that his song 

 shall not go unheard and if we examine a female 

 cricket, that is to say a cricket which has no sound- 

 producing apparatus, we shall find an oval depres- 

 sion, covered by a membrane, on each of her front 

 legs ; these are her ears and they enable her to hear 

 her mate calling to her. 



We have often heard the song of the grasshopper 

 as we have walked through the fields and he too 

 will occupy our time for a few moments. When he 

 sings, he kicks his legs rather violently and this 

 gives us a clue to the situation of his vocal organs. 

 The inside of each of his hind thighs is ridged and 



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