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Article XVI. 



Remarks on the cause of the Sound produced by Lisects in 

 jiying ; hy Dr. Hermann Burmeister, of the University 

 of Berlin. 



From Poggendorff 's Annalen derPhysik und Chemie, vol. xxxviii. No. 6. p. 283.* 



It is ail opinion generally entertained by natural philosophers, that 

 the sound which insects produce during their flight arises from a vibration 

 of the wings. This notion can have had its origin only in the circum- 

 stance that no one had taken the trouble to examine sufficiently into the 

 mechanism which produces the sound. I feel myself the more justified 

 in making this assertion, as I find merely incidental remarks on the 

 buzzing of insects recorded by naturalists, who notice the phsenomenon 

 only for the purpose of illustration. Baumgaertner in his " Naturlehre," 

 (3rd edit. 1829, p. 229,) expresses himself thus : "Therefore an insect 

 can produce a sound through the rapid vibration of the wings :" — and 

 Wilh. Weber says in his essay on tubes with tongues (Zungenpfeifen), 

 {Leges OsciUationis oriundce, si dico corpora diversa celeritate oscillantia 

 ita conjunguntur ut oscillare non possunt nisi simul et synchronice, ex- 

 emplo illustratcB tubulorum linguatorum — Halse 1827, "tto,) Page 1 : 

 "Insecta v, c. qucedam volantia motu alarum sonum certce ultitudinis pro- 

 ferunt : alcE vero neutiquam i?i ipsis insita earumque partes ad cequili- 

 brium repelknte agitantur, sedvi extra alas posita, musculorum nimirum 

 etnervorumr In both cases, therefore, the cause of the sound is referred 

 to the motion of the wing as a vibrating body. 



In the course of an investigation of the different methods by which 

 insects produce sound, with the view of communicating them in my 

 Manual of Entomology (vol. i. p. 509, Berlin, 1 832), my attention was first 

 directed to this subject, and I soon found that the wings have no part 

 whatever in the formation of the sound, for the hum of the insect 

 continues even when its wings are entirely cut away. I perceived, 

 however, a different pitch of the sound ; and remarked that the more 

 of the wing was taken away the higher this became. The insect on 

 which I made my experiments was Eristalis tenax. I have at this time 

 no living specimen of this species at hand, but have now another dipte- 

 rous insect still larger, the Tabanus bovimis, on which I have repeated 

 all my experiments, and obtained precisely the same result. It appeared to 



• The Editor is indebted for the translation to Mr. W. Francis of Berlin. 



