NOISES OF INSECTS. 5S3 



as well as that of other Diptera. The warmer the 

 weather, the greater is their thirst for blood, the more 

 forcible their flight, the motion of their wings more ra- 

 pid, and the sound produced by that motion more in- 

 tense. In the night — but perhaps this may arise from 

 the universal stillness that then reigns — their hum ap- 

 pears louder than in the day: whence its tones may 

 seem to be modified by the will of the animal. 



Sounds also are sometimes emitted by insects when 

 they are feeding or otherwise etnploj/ed. The action of 

 the jaws of a large number of cockchafers produces a 

 noise resembling the sawing of timber ; that of the 

 locusts has been compared to the crackling- of a flame 

 of fire driven by the wind ; indeed the collision at the 

 same instant of myriads of millions of their powerful 

 jaws must be attended by a considerable sound. The 

 timber-borers also — the Bupresfes ; the stag-horn bee- 

 tles (Lucani) ; and particularly the capricorn-beetles 

 (Cerambj/cidce) — the mandibles of whose larvae resem- 

 ble a pair of mill-stones^ — most probably do not feed in 

 silence. A little wood-louse (Psociis pidsatorius, Latr.) 

 — which on that account has been confounded with the 

 death-watch — is said also, when so engaged, to emit a 

 ticking noise. — Certain two-winged flies seen in spring-, 

 distinguished by a very long proboscis (Bomhi/lms, L.), 

 hum all the time that they suck the honey from the 

 flowers ; as do also many hawk-moths, particularly that 

 called from this circumstance the humming-bird (Sp/»"//.r 

 Stellatarum L.), which, while it hovers over them, un- 

 folding its long tongue, pilfers their sweets without in- 

 terrupting its song. — The giant cock-roach {Blatla 



" Linn. Tram. v. 255. i, x\\. f. 7. b. 



