On the 2nd of July I witness a migration. At the hottest time of the day, about two o’clock, the new-born Lice leave their fortress in an innumerable swarm. The young Kermes emerge hastily from the door of their dwelling, the button-hole-shaped cleft; many of them dragging behind them the discarded husk of the egg. For a moment they stand motionless on the domed roof of their spherical house; then they scatter over the neighbouring twigs. Several of them climb upwards and reach the summit of the plant, without appearing to gain much satisfaction from their ascent; some of them climb downwards along their twig, so that I cannot possibly guess what objective the swarm is seeking. It may be that we are witnessing a brief period of disorder, due to the joy of the first few steps in a world of unrestricted freedom; the tiny creatures may be wandering at random, abandoned to the delights of emancipation. Let them do as they will; they will soon quiet down. On the following day, indeed, I can no longer see a single Louse on the tree; all have found their way downwards to the black leaf-mould in the flowerpot, not far from the main stem. This mould, recently watered, is rich in the savours of foliage which has rotted and fallen into dust. There, on a surface barely larger than one’s fingernail, the little creatures have gathered into a closely packed flock. Not one of them moves, so well satisfied do they seem with their pasture, or rather their watering-place. As far as I can see they are feeding, motionless in their well-being. I do what I can to increase their felicity. To keep the place cool and to provide a little shadow I cover it with a few dead leaves from the evergreen oak, previously moistened in a glass of water. And now, little Lice, you must proceed after your own fashion; I have done for you all that I can! I have just learned of one essential point of your history, one detail, without which all the rest of my investigations must inevitably have come to naught. My first conjectures, although perfectly reasonable, were unfounded. Instead of settling down on some twig, as their mother did before them, the young Lice descend to the ground at the foot of their natal tree. There, in the midst of the mosses and dead leaves, they find a shelter offering some degree of coolness, which will nourish them with its exudations, at all events at the outset. And what do they live upon later?—I am not in a position to say. For five or six days I find them on the same spot, a motionless flock. Not one of them leaves the flock, not one of them descends underground. Then their numbers begin to diminish; little by little they all disappear, evaporating as it were, returning to that nothingness from which they were so little removed. The flock of atomies has left not a trace.