Social Life in the Insect World

by Jean-Henri Fabre

If the twig is irregular in shape, or if several Cigales have been working successively at the same point, the distribution of the punctures is confused; the eye wanders, incapable of recognising the order of their succession or the work of the individual. One characteristic is always present, namely, the oblique direction of the woody fragment which is raised by the perforation, showing that the Cigale always works in an upright position and plunges its rostrum downwards in the direction of the twig.

If the twig is regular, smooth, and conveniently long the perforations are almost equidistant and lie very nearly in a straight line. Their number varies; it is small when the mother, disturbed in her operations, has flown away to continue her work elsewhere; but they number thirty or forty, more or less, when they contain the whole of her eggs.

Each one of the perforations is the entrance to an oblique tunnel, which is bored in the medullary sheath of the twig. The aperture is not closed, except by the bunch of woody fibres, which, parted at the moment when the eggs are laid, recover themselves when the double saw of the oviduct is removed. Sometimes, but by no means always, you may see between the fibres a tiny glistening patch like a touch of dried white of egg. This is only an insignificant trace of some albuminous secretion accompanying the egg or facilitating the work of the double saw of the oviduct.

Immediately below the aperture of the perforation is the egg chamber: a short, tunnel-shaped cavity which occupies almost the whole distance between one opening and that lying below it. Sometimes the separating partition is lacking, and the various chambers run into one another, so that the eggs, although introduced by the various apertures, are arranged in an uninterrupted row. This arrangement, however, is not the most usual.

The contents of the chambers vary greatly. I find in each from six to fifteen eggs. The average is ten. The total number of chambers varying from thirty to forty, it follows that the Cigale lays from three to four hundred eggs. Réaumur arrived at the same figures from an examination of the ovaries.

This is truly a fine family, capable by sheer force of numbers of surviving the most serious dangers. I do not see that the adult Cigale is exposed to greater dangers than any other insect: its eye is vigilant, its departure sudden, and its flight rapid; and it inhabits heights at which the prowling brigands of the turf are not to be feared. The sparrow, it is true, will greedily devour it. From time to time he will deliberately and meditatively descend upon the plane-trees from the neighbouring roof and snatch up the singer, who squeaks despairingly. A few blows of the beak and the Cigale is cut into quarters, delicious morsels for the nestlings. But how often does the bird return without his prey! The Cigale, foreseeing his attack, empties its intestine in the eyes of its assailant and flies away.

But the Cigale has a far more terrible enemy than the sparrow. This is the green grasshopper. It is late, and the Cigales are silent. Drowsy with light and heat, they have exhausted themselves in producing their symphonies all day long. Night has come, and with it repose; but a repose frequently troubled. In the thick foliage of the plane-trees there is a sudden sound like a cry of anguish, short and strident. It is the despairing lamentation of the Cigale surprised in the silence by the grasshopper, that ardent hunter of the night, which leaps upon the Cigale, seizes it by the flank, tears it open, and devours the contents of the stomach. After the orgy of music comes night and assassination.

I obtained an insight into this tragedy in the following manner: I was walking up and down before my door at daybreak when something fell from the neighbouring plane-tree uttering shrill squeaks. I ran to see what it was. I found a green grasshopper eviscerating a struggling Cigale. In vain did the latter squeak and gesticulate; the other never loosed its hold, but plunged its head into the entrails of the victim and removed them by little mouthfuls.