158 EVENINGS AT THE MICROSCOPE. 



CHAPTER X. 



INSECTS : THEIR EARS AND EYES. 



A VERY wide field of observation, and one easily culti- 

 vated, is presented by the organs of sense in the Insect 

 races, and in particular by those curious jointed threads 

 which proceed from the front or sides of the head, and 

 which are technically called antenna. These may some- 

 times be confounded with the jmlpi, examples of which 

 organs we have been lately looking at ; for in a carnivor- 

 ous Beetle, for instance, both palpi and antenna are 

 formed of a number of oblong, polished hard joints, set 

 end to end, like beads on a necklace. And it is probable 

 there may be as much that is alike in the function as in 

 the form of these two sets of appendages ; that both are 

 the seats of some very delicate perceptive faculty allied to 

 touch, but of which we cannot, from ignorance, speak 

 very definitely. It is likely, indeed, that sensations of a 

 very variable character are felt by them, according to their 

 form, the degree of their development, and the habits of 

 the species. 



It is not impossible, judging from the very great diver- 

 sity which we find in the form and structure of these and 

 similar organs in this immense class of beings, compared 

 with the uniformity that prevails in the organs of sense 

 bestowed on ourselves and other vertebrate animals, that 

 a far wider sphere of perception is open to them than to 

 us. Perhaps conditions that are perceptible to us only by 

 the aid of the most delicate instruments of modern science 

 may be perceptible to their acute faculties, and may 



