SENSES OF INSECTS. 255 



posed to admit that the primary and most universal 

 function of the antennae is to be the organs of a sense, if 

 not the same, at least analogous to hearing, and answer- 

 ing the same end; something perhaps between it and 

 touch. In some, however, as has been found in the 

 Crustacea, an organ of hearing, in the ordinary sense, 

 may exist at the base of the antennae, which may act the 

 part in some measure of the external ear, and collect 

 and transmit the sound to such organ a . 



That numerous antennae, as a secondary function, ex- 

 plore by touch, is admitted on all hands, and therefore I 

 need not enlarge further upon this point ; but shall pro- 

 ceed to inquire whether insects do not possess some 

 other peculiar organs that are particularly appropriated 

 to this sense. First, however, I must make some gene- 

 ral observations upon it. Of all our senses, touch is the 

 only one that is not confined to particular organs, but 

 dispersed over the whole body : insects, however, from 

 the indurated crust with which they are often covered, 

 feel sensibly, it is probable, only in those parts where 

 the nerves are exposed, by being covered with a thinner 

 epidermis, to external action. Not that they cannot feel 

 at all in their covered parts ; for as we feel sufficiently for 

 walking, though our feet are covered by the thick sole 



a Marcel de Serres thinks he has discovered an organ of hearing 

 in most insects, but he does not state its situation. Mem. du Mus. 

 1819. 99. Treviranus, with regard to the Blattina, suspects it to be 

 situated between the eye and the base of the antennas, perhaps al- 

 luding to the spot noticed above. (VoL. III. p. 505.) Carus, who 

 mentions the above, says, " Is it not reasonable to ask if the sense 

 of hearing may not reside in the membrane which connects the an- 

 tennae with the head ?" Introd. to Comp. Anat. i. 80 . 



