98 INSECT MISCELLANIES. 



suddenly propelled against these scales by the ac- 

 tion of the wings. M. Lorrey again states that the 

 sound arises from the air escaping rapidly through 

 peculiar cavities communicating with the spiracles, 

 and furnished with a fine tuft of hairs on the sides 

 of the abdomen *. M. Passerini, curator of the 

 Museum of Natural History at Florence, has lately 

 investigated the subject more minutely. He traced 

 the origin of the sound to the interior of the head, 

 in which he discovered a cavity at the passage where 

 muscles are placed for impelling and expelling the air. 

 M. Dumeril has since discovered a sort of membrane 

 stretched over this cavity like, as he says, to the head 

 of a drum. M. Duponchel has also confirmed by 

 experiment the opinions of Passerini and Dumeril, 

 and confutes Lorrey, by stating that the noise is pro- 

 duced from the head when the body of the insect is 

 removed t- 



The death's-head moth is not the only insect whose 

 sound alarms the superstitious. Insects, which are 

 much more common, though from their minuteness 

 not so often seen as heard, often strike the unedu- 

 cated with terror as the messengers of death. We 

 refer to the sound which most of our readers may 

 have heard issuing from old timber or old books, 

 resembling the ticking of a watch, and hence popu- 

 larly called the death-watch. Some writers, who 

 are desirous of being thought very accurate, are 

 particular in distinguishing a certain insect as the 

 genuine death-watch, while others are held to be 

 spurious ; yet there can be no doubt that the same 

 sort of ticking is produced by several species. La- 

 treille, indeed, seems to say that it is common to a 

 whole genus (Anobium, FABR. J) ; and besides these, 



* Stephens's Illustr. (Haust.) i. 116. 



k t Annales des Sciences Naturelles, Mars., 1828. 



J Families Naturelles, i. 484, ed. 1829. 



