THE MICROSCOPE AND INSECT LIFE 



shaped. At length the time comes when they 

 straighten their tails somewhat violently, their skin 

 splits along the back and out comes the perfect 

 gnat. We can use him for further microscopic work, 

 so we will not let him go. If he be a male, his 

 beautiful feathered feelers or, if a female, her thread- 

 like feelers will make good objects for us, the scales 

 from head and body, the wings and feet are all 

 worth the time we may spend in examining them. 

 The mouth parts, too, are interesting but rather 

 complicated. 



Many insects are capable of emitting more or less 

 musical sounds. In some countries these so-called 

 singing insects are kept as pets, in other countries 

 the same insects are voted a nuisance; it is all a 

 matter of taste. Of all musical insects, the most 

 noted is the Cicada and its sound organs are easily 

 seen; they occur only in the male, for the female 

 never sings. The Cicada belongs to the same great 

 order of insects as the green fly, which we have 

 already mentioned. There is one British species, 

 and our readers who visit the New Forest may come 

 upon it. On the under side of one of these insects 

 the beak, very similar to the beak of the green fiy, 

 may be plainly seen. On either side of the insect, 

 just below the bases of the wings there are two 

 nearly round discs. These discs cover the sound 

 organs, which are two ear shaped membranes. By 

 means of muscles the insect can cause the mem- 

 branes to vibrate and thus produce the sound which 

 once heard, can never be forgotten. 



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