ORGANS OF HEARING. 181 



with nerves of an extraordinary thickness in pro- 

 portion to their own size, there cannot remain a 

 doubt that they are organs of some sense, and that 

 too a very acute one. 



" I have said, that insects are proved by obser- 

 vation to be furnished with an organ of hearing. It 

 is, indeed, scarcely probable that creatures such as 

 the tree-hopper (Cicada), and the locust (Locusta), 

 to which nature has given the faculty of producing 

 a peculiar sound, by means of an appropriate organ, 

 should, at the same time, be deprived of the means 

 of hearing such sounds, inasmuch as these can have 

 reference only to their own kindred. It is still 

 farther proved, that these insects share the faculty 

 of hearing, along with all other living beings, by 

 their ceasing to sing the instant they fear they 

 have been discovered." * 



" I once was observing," says Kirby, " the mo- 

 tions of a weevil (Apion) under a pocket micro- 

 scope : on seeing me, it receded. Upon my making 

 a slight but distinct noise, its antennae started : I 

 repeated the noise several times, and invariably 

 with the same effect. A beetle (Harpalus,') which 

 I was holding in my hand, answered the sound in 

 the same manner repeatedly. I will now mention 

 another effect that I observed, still more remark- 

 able. A little moth was reposing upon my window ; 



* See Field Naturalist's Magazine, i. pp. 59, 60, 



