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LETTER XXIV. 
ON THE NOISES PRODUCED BY INSECTS. 
Trar insects, though they fill the air with a variety of sounds, have no 
voice, may seem to you a paradox, and you may be tempted to exclaim with 
the Roman naturalist, What, amidst this incessant diurnal hum of bees ; 
this evening boom of beetles; this nocturnal buzz of gnats; this merry 
chirp of crickets and grasshoppers; this deafening drum of Cicade, have 
insects no voice! If by voice we understand sounds produced by the air 
expelled from the lungs, which, passing through the larynx, is modified by 
the tongue, and emitted from the mouth,—it is even so. For no insect, 
like the larger animals, uses its mouth for utterance of any kind: in this 
"respect they are all peey mute ; and though incessantly noisy, are ever- 
lastingly silent. Of this fact the Stagyrite was not ignorant, since, deny- 
ing them a voice, he attributes the sounds emitted by insects to another 
cause. But if we feel disposed to give a larger extent to this word ; if we 
are of opinion that all sounds, however produced, by means of which ani- 
mals determine those of their own species to certain actions, merit the 
name of yoice; then I will grant that insects have a voice. But, decide 
this question as we will, we all know that by some means or other, at 
certain seasons and on various occasions, these little creatures make a 
great din in the world. I must therefore now bespeak your attention to 
this department of their history. 
In discussing this subject, [ shall consider the noises insects emit — 
during their motions — when they are feeding, or otherwise employed — 
when they are calling or commanding—or when they are under the in- 
fluence of the passions ; of fear, of anger, of sorrow, joy, or love. . 
The only kind of ocomotion during which these animals produce sounds 
is flying: for though the hill-ants (Formica rufa), as I formerly observed, 
make a rustling noise with their feet when walking over dry leayes, I know 
of no other insect the tread of which is accompanied by sound — except 
indeed the flea, whose steps, a lady assures me, she always hears when it 
paces over her night-cap, and that it clicks as if walking on pattens! That 
the flight of numbers of insects is attended by a humming or booming is 
known to almost every one; but that the great majority move through 
the air in silence, has not perhaps been so often observed. Generally 
apephing, those that fly with the greatest force and rapidity, and with wings 
seemingly motionless, make the most noise ; while those that fly gently and 
leisurely, and visibly fan the air with their wings, yield little or no sound. 
Amongst the beetle tribes (Coleoptera) none is more noticed, or more 
celebrated for “wheeling its droning flight,” than the common dung- 
chafer (Geotrupes stercorarius) and its affinities. Linné affirms—but the 
