HEARING IN INSECTS. 



97 



the body are held firmly down. Reaumur, after 

 many experiments, concludes, that " in the more 

 minute parts of Nature's works there is always some- 

 thing which we cannot explain." It appeared to him 

 most probable that the cry came from the head, per- 

 haps from the mouth, or rather from the tongue, and 

 it mio;ht be by friction of the palpi against the tongue ; 

 for when he unfolded the spiral tongue with a pin, 

 the cry ceased, but was renewed the instant it was 

 coiled up again between the palpi. He then pre- 

 vented the palpi from touching the tongue, which 

 also stopt the sound, and when only one was per- 

 mitted to touch it, the sound was much more feeble* 



■Reaumur's experiments on tlie death's-head hawk-moth, a, the tongue 

 unfolded with a pin ; b, the palpi prevented from touching the tongue. 



Huber, without mentioning the particulars, says 

 he has ascertained that Reaumur was quite mis- 

 taken t- En2:ramelle informs us that M. de Johet 

 plucked out the jaws {maxillcE) and cut off the palpi 

 of one of these moths, and yet the noise was pro- 

 duced when the wings were agitated. Being thence 

 led to examine the wings, he found two concave 

 scales at their base, which he supposes may be the 

 organs of sound ; and when the scales were cut otF, 

 the insect, he says, became mute. M. de Johet 

 thinks the sound is produced by the air being 



Memoires, ii. 293, 



f On Bees, p. 313, Note. 

 K 



