The Life of the Grasshopper

by Jean-Henri Fabre

With this same mechanism of a drum and file, which of them will achieve any progress? Not one of the large-winged Locustidæ succeeds in doing so. All, from the biggest, the Grasshoppers, Dectici and Conocephali, down to the smallest, the Platycleis, Xiphidion and Phaneropteron, set in motion with the teeth of a bow the frame of a vibrating-mirror; all are, so to speak, left-handed, that is to say, they carry the bow on the lower [[267]]surface of the left wing-case, overlapping the right, which is furnished with the tympanum; all, lastly, have a thin, faint trill which is sometimes hardly perceptible.

One alone, modifying the details of the apparatus without introducing any innovation into the general structure, achieves a certain power of sound. This is the Vine Ephippiger, who does without wings and reduces his wing-cases to two concave scales, elegantly fluted and fitting one into the other. These two disks are all that remains of the organs of flight, which have become exclusively organs of song. The insect abandons flying to devote itself the better to stridulation.

It shelters its instrument under a sort of dome formed by the corselet, which is curved saddlewise. As usual, the left scale occupies the upper position and bears on its lower surface a file in which we can distinguish with the lens eighty transversal denticulations, more powerful and more clearly cut than those possessed by any other of the Grasshopper tribe. The right scale is underneath. At the top of its slightly flattened dome, the mirror gleams, framed in a strong nervure.

For elegance of structure, this instrument [[268]]is superior to the Cicada’s, in which the contraction of two columns of muscles alternately pulls in and lets out the convex surface of two barren cymbals. It needs sound-chambers, resonators, to become a noisy apparatus. As things are, it emits a lingering and plaintive tchi-i-i, tchi-i-i, tchi-i-i, in a minor key, which is heard even farther than the blithe bowing of the White-faced Decticus.

When disturbed in their repose, the Decticus and the other Grasshoppers at once become silent, struck dumb with fear. With them, singing invariably expresses gladness. The Ephippiger also dreads to be disturbed and baffles with his sudden silence whoso seeks to find him. But take him between your fingers. Often he will resume his stridulation with erratic strokes of the bow. At such times the song denotes anything but happiness, fear rather and all the anguish of danger. The Cicada likewise rattles more shrilly than ever when a ruthless child dislocates his abdomen and forces open his chapels. In both cases, the gay refrain of the mirthful insect turns into the lamentation of a persecuted victim.

A second peculiarity of the Ephippiger’s, [[269]]unknown to the other singing insects, is worthy of remark. Both sexes are endowed with the sound-producing apparatus. The female, who, in the other Grasshoppers, is always dumb, with not even a vestige of bow or mirror, acquires in this instance a musical instrument which is a close copy of the male’s.

The left scale covers the right. Its edges are fluted with thick, pale nervures, forming a fine-meshed network; the centre, on the other hand, is smooth and swells into an amber-coloured dome. Underneath, this dome is supplied with two concurrent nervures, the chief of which is slightly wrinkled on its ridge. The right scale is similarly constructed, but for one detail: the central dome, which also is amber-coloured, is traversed by a nervure which describes a sort of sinuous line and which, under the magnifying-glass, reveals very fine transversal teeth throughout the greater part of its length.

This feature betrays the bow, placed in the inverse position to that which is known to us. The male is left-handed and works with his upper wing-case; the female is right-handed and scrapes with her lower wing-case. [[270]]Besides, with her, there is no such thing as a mirror, that is to say, no shiny membrane resembling a flake of mica. The bow rubs across the rough vein of the opposite scale and in this way produces simultaneous vibration in the two fitted spherical domes.

The vibrating part is double, therefore, but too stiff and clumsy to produce a sound of any depth. The song, in any case rather thin, is even more plaintive than the male’s. The insect is not lavish with it. If I do not interfere, my captives never add their note to the concert of their caged companions; on the other hand, when seized and worried, they utter a moan at once. It seems likely that, in a state of liberty, things happen otherwise. The dumb beauties in my bell-jars are not for nothing endowed with a double cymbal and a bow. The instrument that moans with fright must also ring out joyously on occasion.

What purpose is served by the Grasshopper’s sound-apparatus? I will not go so far as to refuse it a part in the pairing, or to deny it a persuasive murmur, sweet to her who hears it: that would be flying in the face of the evidence. But this is not its principal [[271]]function. Before anything else, the insect uses it to express its joy in living, to sing the delights of existence with a belly well filled and a back warmed by the sun, as witness the big Decticus and the male Grasshopper, who, after the wedding, exhausted for good and all and taking no further interest in pairing, continue to stridulate merrily as long as their strength holds out.