486 NOISES OF INSECTS. 



them, as well as the Trichoptera and Neuroptera, which are equally barren 

 of insects of sounding wing, and proceed to an order, the Hymenoptera, 

 in which the insects that compose it are, many of them, of more fame for 

 this property. 



The indefatigable hive-bee, as she flies from flower to flower, amuses the 

 observer with her hum, which, though monotonous, pleases by exciting the 

 idea of happy industry, that wiles the toils of labour with a song. When 

 she alights upon a flower, and is engaged in collecting its sweets, her hum 

 ceases; but it is resumed again the moment that she leaves it. The wasp 

 and hornet also are strenuous hummers ; and when they enter our apart- 

 ments, their hum often brings terror with it. But the most sonorous flies 

 of this order are the larger humble-bees, whose bombination, booming, or 

 bombing, may be heard from a considerable distance, gradually increasing as 

 the animal approaches you, and when, in its wheeling flight, it rudely passes 

 close to your ear, almost stunning you by its sharp, shrill, and deafening 

 sound. Many genera, however, of this orcfer fly silently. 



But the noisiest wings belong to insects of the dipterous order, a majority 

 of which probably give notice of their approach by the sound of their 

 trumpets. Most of those, however, that have a slender body, the gnat 

 genus (Culex) excepted, explore the air in silence. Of this description 

 are the Tipularice, the Asilidce, the genus Empis, and their affinities. The 

 rest are more or less insects of a humming flight ; and with respect to 

 many of them, their hum is a sound of terror and dismay to those who hear 

 it. To man, the trumpet of the gnat or mosquito, and to beasts, that of 

 the gad-fly, of various kinds of horse-flies, and of the Ethiopian zimb, as I 

 have before related at large, is the signal of intolerable annoyance. Homer, 

 in his Batrachomyomachia, long celebrated the first of these as a trum- 

 peter : 



" For their sonorous trumpets far renown'd, 

 Of battle the dire charge mosquitos sound." 



Mr. Pope, in his translation, with his usual inaccuracy, thinking, no doubt, 

 to improve upon his author, has turned the old bard's gnats into hornets. 

 In Guiana these animals are distinguished by a name still more tremendous, 

 being called the devil's trumpeters. 1 I have observed that early in the 

 spring, before their thirst for blood seizes them, gnats when flying emit 

 no sound. At this moment (Feb. 18.)'two females are flying about my 

 windows in perfect silence. 



After this short account of insects that give notice when they are upon 

 the wing by the sounds that precede them, I must inquire by what means 

 these sounds are produced. . Ordinarily, except perhaps in the case of the 

 gnat, they seem perfectly independent of the will of the animal; and in 

 almost every instance, the sole instruments that cause the noise of flying 

 insects are their wings, or some parts near to them, which, by their friction 

 against the trunk, occasion a vibration as the fingers upon the strings of 

 a guitar yielding a sound more or less acute in proportion to the rapidity 

 of their flight, the action of the air perhaps upon these organs giving it 

 some modifications. Whether, in the beetles that fly with noise, the elytra 

 contribute more or less to produce it, seems not to have been clearly ascer- 

 tained : yet, since they fly with force as well as velocity, the action of the air 



* Stedman's Surinam, i. 24. 



