296 ANATOMY. 



individual insects, to which cavities nervous filaments were said to be 

 distributed*. It is evident that some misconception was here at work, 

 for no entomotomist, either before him or since, has seen any thing of the 

 kind. But as insects doubtlessly hear, as some, for example, the Cicada, 

 grasshoppers, many beetles, &c., produce a peculiar sound, which serves 

 to attract the attention of the female, they must evidently be provided 

 with an organ of hearing, which is either very recondite, or referred to 

 organs whose form does not evince their function. The antennae are 

 doubtlessly of this class, and, indeed, Sulzer, Scarpa, Schneider, 

 Borkhausen, Reaumur, and Bonnsdorf, considered them as organs of 

 hearing. That they are not organs of touch, is proved anatomically by 

 their horny hard upper surface, and physiologically by the observation 

 that insects never use them as such, this function being exercised by 

 other organs, namely, the palpi. Besides, the analogy of the crabs, in 

 which it is well known that the organ of hearing lies at the base of the 

 large antennae, speaks in favour of the adoption of the opinion of their 

 being in general organs of hearing. If after this hint we look to the 

 insertion of the antenna?, we likewise detect here a soft articulating 

 membrane, which lies exposed, and which is rendered tense by the 

 motion of the antennae. This membrane, beneath which the nerve of 

 the antennae runs, might, without much inconsistency, be explained as 

 the drum of the ear, and thus would the antennae be transformed pelices, 

 which, as very moveable parts, would receive the vibrations of the air, 

 caused by sound, and act as a conductor to it. Whoever has observed 

 a tranquilly proceeding Capricorn beetle, which is suddenly surprised 

 by a loud sound, will have seen how immoveably outwards it spreads 

 its antennae, and holds them porrect as it were with the greatest atten- 

 tion as long as it listens, and how carelessly the insect proceeds in its 

 course when it conceives that no danger threatens it from the unusual 

 noise. CarusJ, Straus Durkheim , and Oken ||, are of the same 

 opinion, and which I have entertained for years, and endeavoured to 

 confirm myself in by numerous experiments. 



* Schelver, as above, p. 51. f Ib. p. 24. J Zootomie, p. 65. 



Consid. Generates, p. 415, &c. 



|| It was not unpleasing to me to find in the recent edition of Okeu's Naturphilosophie, 

 my opinion stated in almost the same words in which I wrote them down. Consult that 

 work, p. 421, No. 3355. The earlier edition of this work did not contain the idea. See 

 Vol. iii. p. 274, No. 3100. 



