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MEANS OF DEFENCE OF INSECTS. 



when I found several feeding in a ram's horn. 1 The " drowsy 

 hum " of beetles, humble-bees, and other insects, in their 

 flight, may tend to preserve them from some of their aerial 

 assailants. And the angry chidings of the inhabitants of the 

 hive, which are very distinguishable from their ordinary 

 sounds, may be regarded as warning voices to those from 

 whom they apprehend evil or an attack. I have before ob- 

 served that the death's-head hawk-moth (Acherontia Atropos), 

 when menaced by the stings of ten thousand bees enraged at 

 her depredations upon their property, possesses the secret to 

 disarm them of their fury. This insect, when in fear or 

 danger, is known to produce a sharp, shrill, mournful cry, 

 which with the superstitious has added to the alarm produced 

 by the symbol of death which signalises its thorax. This 

 cry, there is reason to believe, affects and disarms the bees, 

 so as to enable her to proceed in her spoliations with im- 

 punity. 2 One of these insects being once brought to a 

 learned divine, who was also an entomologist, when he was 

 unwell, he was so much moved by its plaintive noise, that, 

 instead of devoting it to destruction, he gave the animal its 

 life and liberty. I might say more upon this subject of 

 defensive noises, but I shall reserve what I have further to 

 communicate, to a letter which I purpose devoting to the 

 sounds produced or emitted by insects. 



You are acquainted with the singular property of the 

 skunk ( Viverra putorius L.), which repels its assailants by 

 the fetid vapour that it explodes ; but perhaps are not aware 

 that the Creator has endowed many insects with the same 

 property, and for the same purpose, some of which exhale 

 powerful or disagreeable odours at all times, and from the 

 general surface of their body ; while they issue from others 

 only through particular organs, and when they are attacked. 



Of the former description of defensive scents there are 

 numerous examples in almost every order; for, next to 



1 Numerous other beetles make the same kind of sound, either by the friction 

 of the head in the anterior prothoracic cavity, or by rubbing the narrowed front 

 of the mesothorax against the sides of the posterior prothoracic cavity, or the 

 abdomen against the elytra. 



2 Huber appears to be of this opinion ; he does not, however, lay great stress 

 upon it. Yet there seems no other way of accounting for the impunity with 

 which this animal commits its depredation. Huber, ii. 299. 



