Generation of Sounds by Canadian Insects. 125 



rity of Captain Hancock, that the Brazilian Cicadas, sing so loud 

 as to be heard at the distance of a mile, which is as if a man of 

 ordinary stature possessed a voice that could be heard all over the 

 world. That its voice is very much louder than our Canadian 

 species, may very well be understood, when it is remembered that 

 the Brazilian Cicada is a much larger species, and I am informed 

 that its drum is similar to the one which has been described. 

 The use of the music, as in crickets, and other insects, is for the 

 the purpose of attracting the female sex, and it conclusively shows 

 that if the precise organ of hearing has not been definitely recog- 

 nized in them, it at any rate is most assuredly not absent. New- 

 man has observed, "to what purpose would the merry cricket sing 

 his evening song, if there w T ere none of his kind to listen to and 

 admire it ?" 



Any one who has walked across a Canadian meadow or pasture 

 land, in the summer time, or over a hay field, particularly after 

 the hay has been cut and removed, must have observed the count- 

 less numbers of grass-hoppers, locusts, crickets, and other insects, 

 which hop across his path, and produce with their united voices 

 a chirping noise not easily forgotten. Some of the locusts pos- 

 sess yellow wings with a black border, and as they fly, produce a 

 sort of loud snapping noise, which is very peculiar.* This is pro- 

 duced by the attrition of the anterior pairs of wings against each 

 other, one of the nervures being furnished with a rough file-like 

 edge, which is made to pass over the nervures of the opposite 

 wing ; and the sound is augmented by the resonance of a certain 

 part of the wing, that is surrounded by peculiarly strong nervures, 

 between which the thin membrane is tightly stretched, so that it 

 acts as a tympanum or drum. In other species of Canadian lo- 

 custs there exists on each side of the body near the base of the 

 abdomen, a large cavity, closed on the inside by a very thin pelli- 

 cle, which has some influence in the production of chirping, or 

 possibly as has been supposed in flight. It is in this respect an- 

 alogous to the tree-hoppers, and may be compared to a kind of 

 tambour or drum. The opening left by the pellicle, which answers 

 the purpose of a lid, is crescentic in shape, and at the bottom of 

 the cavity may be seen a white membrane shining like a mirror 



* This insect is called the Rattling Locust JEdipoda sulphured, and 

 possesses dusky elytrae. I have noticed the wing3 vary in colour, but the 

 yellow are the commonest with a black border. 



