THE SENSES OF INSECTS. 31 



the drum-like space to the body of the violiu. Thus, most 

 grasshoppers are fiddlers, and during the summer, both by 

 day and night, the air resounds with the music of these 

 primitive violinists. This noise may add to our pleasure, or 

 become tedious and disagreeable. This makes little differ- 

 ence, for insect-music is all-important. It is the cricket's 

 love-call; and were crickets, etc., deaf and dumb, we are 

 safe in saying the breed would soon run out, because they 

 would not otherwise readily mate. 



Insects also have the sense of touch highly developed; its 

 seat is in the numerous hairs and bristles which clothe the 

 antennae and palpi, as well as the legs and the body itself.* 



The hairs of insects form an interesting subject for micro- 

 scopic study, since they vary so much in shape. The simplest 

 are seen in the smaller caterpillars, and the larger naked 

 kinds, in which the hairs are minute and very slender; 

 while in the hairy species, as the arctians, they are densely 

 barbed ; in certain caterpillars, as those of the maia, io, and 

 the native silk-worm moths, the hairs are spine-like, with 

 sharp spinules, and are poisonous, having at their base a 

 minute poison-gland. Hairy or spiny caterpillars are not 

 eaten by birds, or so easily molested by ichneumon-flies. 

 The hairs sometimes become flat and broad as in the scales 

 of moths and butterflies, as well as certain flies and beetles. 



* To examine the heads of insects in order to watch the movements 

 of the appendages and mouth-parts, we may sometimes follow with 

 advantage Mr. E. T. Draper's recommendation of using a cone of 

 pasted paper to be made rather larger than the specimen, with the 

 apex cut off. A vigorous insect will soon project its head through 

 the aperture. When in this position it should be blocked behind 

 with cotton wool slightly wetted. The cone can then be gummed 

 to a slip, apex upward. Insects held in this way will allow one to 

 observe the movements of the antenna?, palpi, jaws, etc., and the 

 effects produced by excitation with saccharine or nitrogenous fluids, 

 administered with a sable pencil. (Science- Gosx/'p, 1884, 26.) 



