I have just been practising on insects tricks which to all appearances are as puerile as those which we practised on the Turkeys in the days when the farmer's wife used to run after us cracking her whip. Do not laugh: a serious problem looms behind this artlessness.
My insects' condition bears a strange resemblance to that of my poultry. Both present the image of death, inertia, the contraction of convulsed limbs. In both again the immobility is dispelled before its time by the agency of a stimulus, by sound in the case of the bird, by light in that of the insect. Silence, darkness and tranquillity prolong it. Its duration varies greatly in different species and appears to increase with corpulence.
Among ourselves, who are very unequal subjects for induced sleep, the hypnotist is obliged to pick and choose. He succeeds with one and not with another. Similarly, among the insects, a selection is necessary, for they do not all of them, by a long way, respond to the experimenter's attempts. My best subjects have been the Giant Scarites and the Cloudy Buprestis; but how many others have resisted quite indomitably, or remained motionless for only a few seconds!
The insect's return to the active state presents certain peculiarities which are well worthy of attention. The key to the problem lies here. Let us return for a moment to the patients who have been subjected to the ordeal of ether. These are really hypnotized. They do not remain motionless by way of a ruse, there is no doubt upon that point; they are actually on the threshold of death; and, if I did not take them in good time out of the flask in which a few drops of ether have been evaporated, they would never recover from the torpor whose last stage is death.
Now what symptoms herald their return to activity? We know the symptoms: the tarsi tremble, the palpi quiver, the antennæ wave to and fro. A man emerging from a deep sleep stretches his limbs, yawns and rubs his eyes. The insect awaking from the etheric sleep likewise has its own fashion of marking its recovery of consciousness: it flutters its tiny digits and the more mobile of its organs.
Let us now consider an insect which, upset by a shock, perturbed by some sort of excitement, is believed to be shamming dead, lying on its back. The return to activity is announced exactly in the same fashion and in the same order as after the stupefying effect of ether. First the tarsi quiver; then the palpi and antennæ wave feebly to and fro.