What will the little Louse do in her isolated retreat? Feed, and, above all, multiply. If one is to become legion a few months hence, matters brook no delay. Here, then, there is no father, a mere superfluity and waste of time. So many Lice, so many mothers; no more is needed. Nor is there any laying, for the egg would take too long to develop. Nothing short of direct procreation, unfettered by any preliminaries, is acceptable to the Louse’s ardour. The young are born alive and like their mother, except in point of size. As soon as they are brought into the world, they insert their suckers, absorb a little sap, increase in size, and in a few days become capable of continuing the race by the same rapid method, without fathers. Until the end of the annual colonization the offspring, including the remotest degrees of descent, will maintain the process of genesis by direct parturition and will know no other method. When the time has come for a more convenient examination, we shall return to this amazing method, which completely upsets our ideas. On the 1st of May I open some of the purple swellings which have formed on the tips of the burgeoning leaflets. Sometimes I find the maker of the capsule alone, just as she was on the tips of the buds; sometimes she has undergone a moult and is accompanied by the beginnings of a family. After discarding her black slough, she has become greenish, corpulent and lightly dusted with flour. Her youngsters, at the moment one or at most two, are brown, slender and bare-skinned. In order to follow the progress of the family, I place under a glass a couple of capsules which so far contain only the founder. Two days later I have a dozen young Lice, who soon desert the natal pocket and make for the cotton-wool closing the glass tube. This hasty migration indicates that the young Lice have their function elsewhere, on the tender, already unfolded leaves. Detached from its fostering support, the little purple cell dries up and its inhabitant dies. My census can no longer be continued. No matter: I have learnt that one day is enough to produce three births. If this birth-rate persists for a fortnight, the maker of the capsule will have brought forth a handsome family, gradually scattered over the wide field of exploitation offered by the terebinth. A fortnight later the red eggs hatch out, when the young twigs are already shooting and unfolding their leaves. As far as I could judge from my highly unreliable observations of these swarming insects, which are not clearly distinguishable one from the other, the later generation begins as did the earlier. It causes purple nodules to appear on the tips of the leaflets, little wallets similar in shape and size to a grape-stone. Like those already mentioned, these cells are inhabited at first by a single Plant-louse.