The merry inhabitant of our dwellings, the house-cricket (Gryllus domesticus), though it is often heard by day, is most noisy in the night. As soon as it grows dusk, its shrill note increases till it becomes quite an annoyance, and interrupts conversation. When the male sings, he elevates the elytra so as to form an acute angle with the body, and then rubs them against each other by a horizontal and very brisk motion[650]. The learned Scaliger is said to have been particularly delighted with the chirping of these animals, and was accustomed to keep them in a box for his amusement. We are told that they have been sold in Africa at a high price, and employed to procure sleep[651]. If they could be used to supply the place of laudanum, and lull the restlessness of busy thought in this country, the exchange would be beneficial. Like many other noisy persons, crickets like to hear nobody louder than themselves. Ledelius relates that a woman, who had tried in vain every method she could think of to banish them from her house, at last got rid of them by the noise made by drums and trumpets, which she had procured to entertain her guests at a wedding. They instantly forsook the house, and she heard of them no more[652].
The field-cricket (Gryllus campestris) makes a shrilling noise—still more sonorous than that of the house-cricket—which may be heard at a great distance. Mouffet tells us, that their sound may be imitated by rubbing their elytra, after they are taken off, against each other[653]. "Sounds," says Mr. White, "do not always give us pleasure according to their sweetness and melody; nor do harsh sounds always displease.—Thus the shrilling of the field-cricket, though sharp and stridulous, yet marvellously delights some hearers, filling their minds with a train of summer ideas of every thing that is rural, verdurous, and joyous." One of these crickets when confined in a paper cage and set in the sun, and supplied with plants moistened with water—for if they are not wetted it will die—will feed, and thrive, and become so merry and loud, as to be irksome in the same room where a person is sitting[654].
Having never seen a female of that extraordinary animal the mole-cricket (Gryllotalpa vulgaris), I cannot say what difference obtains in the reticulation of the elytra of the two sexes. The male varies in this respect from the other male crickets, for they have no circular area, nor do the nervures run so irregularly; the areolets, however, toward their base are large, with very tense membrane. The base itself also is scarcely at all elevated. Circumstances these, which demonstrate the propriety of considering them distinct from the other crickets. This creature is not however mute. Where they abound they may be heard about the middle of April singing their love-ditty in a low, dull, jarring, uninterrupted note, not unlike that of the goat-sucker (Caprimulgus europæus), but more inward[655]. I remember once tracing one by its shrilling to the very hole, under a stone, in the bank of my canal, in which it was concealed.
Another tribe of grasshoppers (Acrida, Pterophylla, &c.[656])—the females of which are distinguished by their long ensiform ovipositor—like the crickets, make their noise by the friction of the base of their elytra. And the chirping they thus produce is long, and seldom interrupted, which distinguishes it from that of the common grasshoppers (Locusta). What is remarkable, the grasshopper lark (Sylvia locustella), which preys upon them, makes a similar noise. Professor Lichtenstein in the Linnean Transactions has called the attention of naturalists to the eye-like area in the right wing of the males of this genus[657]; but he seems not to have been aware that De Geer had noticed it before him as a sexual character; who also, with good reason, supposes it to assist these animals in the sounds they produce. Speaking of Acrida viridissima—common with us—he says, "In our male grasshoppers, in that part of the right elytrum which is folded horizontally over the trunk, there is a round plate made of very fine transparent membrane, resembling a little mirror or piece of talc, of the tension of a drum. This membrane is surrounded by a strong and prominent nervure, and is concealed under the fold of the left elytrum, which has also several prominent nervures answering to the margin of the membrane or ocellus. There is," he further remarks, "every reason to believe that the brisk movement with which the grasshopper rubs these nervures against each other, produces a vibration in the membrane augmenting the sound. The males in question sing continually in the hedges and trees during the months of July and August, especially towards sun-set and part of the night. When any one approaches they immediately cease their song[658]."
The last description of singers that I shall notice amongst the Locustina, and which includes the migratory locust, are those that are more commonly denominated grasshoppers. To this genus belong the little chirpers that we hear in every sunny bank, and which make vocal every heath. They begin their song—which is a short chirp regularly interrupted, in which it differs from that of the Acridæ—long before sun-rise. In the heat of the day it is intermitted, and resumed in the evening. This sound is thus produced:—Applying its posterior shank to the thigh, the animal rubs it briskly against the elytrum[659], doing this alternately with the right and left legs, which causes the regular breaks in the sound. But this is not their whole apparatus of song—since, like the Tettigoniæ, they have also a tympanum or drum. De Geer, who examined the insects he describes with the eye of an anatomist, seems to be the only entomologist that has noticed this organ. "On each side of the first segment of the abdomen," says he, "immediately above the origin of the posterior thighs, there is a considerable and deep aperture of rather an oval form, which is partly closed by an irregular flat plate or operculum of a hard substance, but covered by a wrinkled flexible membrane. The opening left by this operculum is semi-lunar, and at the bottom of the cavity is a white pellicle of considerable tension, and shining like a little mirror. On that side of the aperture which is towards the head, there is a little oval hole, into which the point of a pin may be introduced without resistance. When the pellicle is removed, a large cavity appears. In my opinion this aperture, cavity, and above all the membrane in tension, contribute much to produce and augment the sound emitted by the grasshopper[660]." This description, which was taken from the migratory locust (L. migratoria), answers tolerably well to the tympanum of our common grasshoppers, only in them the aperture seems to be rather semicircular, and the wrinkled plate—which has no marginal hairs—is clearly a continuation of the substance of the segment. This apparatus so much resembles the drum of the Cicadæ, that there can be little doubt as to its use. The vibrations caused by the friction of the thighs and elytra striking upon this drum, are reverberated by it, and so intenseness is given to the sound. In Spain, we are told that people of fashion keep these animals—called there Grillo—in cages, which they name Grilleria, for the sake of their song[661].
I shall conclude this diatribe upon the noises of insects, with a tribe that have long been celebrated for their musical powers: I mean the Cicadiadæ, including the genera Fulgora, Cicada, Tettix, and Tettigonia[662]. The Fulgoræ appear to be night-singers, while the Cicadæ sing usually in the day. The great lantern-fly (Fulgora laternaria), from its noise in the evening—nearly resembling the sound of a cymbal, or razor-grinder when at work—is called Scare-sleep by the Dutch in Guiana. It begins regularly at sun-set[663]. Perhaps an insect mentioned by Ligon as making a great noise in the night in Barbadoes, may belong to this tribe. "There is a kind of animal in the woods," says he, "that I never saw, which lie all day in holes and hollow trees, and as soon as the sun is down begin their tunes, which are neither singing nor crying, but the shrillest voices I ever heard: nothing can be so nearly resembled to it as the mouths of a pack of small beagles at a distance; and so lively and chirping the noise is, as nothing can be more delightful to the ears, if there were not too much of it; for the music hath no intermission till morning, and then all is husht[664]."
The species of the other genus, Cicada, called by the ancient Greeks—by whom they were often kept in cages for the sake of their song—Tettix, seem to have been the favourites of every Grecian bard from Homer and Hesiod to Anacreon and Theocritus. Supposed to be perfectly harmless, and to live only upon the dew, they were addressed by the most endearing epithets, and were regarded as all but divine. One bard entreats the shepherds to spare the innoxious Tettix, that nightingale of the Nymphs, and to make those mischievous birds the thrush and blackbird their prey. Sweet prophet of the summer, says Anacreon, addressing this insect, the Muses love thee, Phœbus himself loves thee, and has given thee a shrill song; old age does not wear thee out; thou art wise, earth-born, musical, impassive, without blood; thou art almost like a god[665]. So attached were the Athenians to these insects, that they were accustomed to fasten golden images of them in their hair, implying at the same time a boast that they themselves, as well as the Cicadæ, were Terræ filii. They were regarded indeed by all as the happiest as well as the most innocent of animals—not, we will suppose, for the reason given by the saucy Rhodian Xenarchus, when he says,
"Happy the Cicadas' lives,
Since they all have voiceless wives."
If the Grecian Tettix or Cicada had been distinguished by a harsh and deafening note, like those of some other countries, it would hardly have been an object of such affection. That it was not, is clearly proved by the connexion which was supposed to exist between it and music. Thus the sound of this insect and of the harp were called by one and the same name[666]. A Cicada sitting upon a harp was a usual emblem of the science of music, which was thus accounted for:—When two rival musicians, Eunomus and Ariston, were contending upon that instrument, a Cicada flying to the former and sitting upon his harp, supplied the place of a broken string, and so secured to him the victory[667]. To excel this animal in singing seems to have been the highest commendation of a singer; and even the eloquence of Plato was not thought to suffer by a comparison with it[668]. At Surinam the noise of the Cicada Tibicen is still supposed so much to resemble the sound of a harp or lyre, that they are called there harpers (Lierman)[669]. Whether the Grecian Cicadæ maintain at present their ancient character for music, travellers do not tell us.