The Pine Processionary knows nothing of privation. He knows as little of family ties, another source of unrelenting competition. To make ourselves a place in the sun is but a half of the struggle imposed upon us by life: we must also, as far as possible, prepare a place for our successors; and, as the preservation of the species is of greater importance than that of the individual, the struggle for the future is even fiercer than the struggle for the present. Every mother regards the welfare of her offspring as her primary law. Perish all else, provided that the brood flourish! Every one for himself is her maxim, imposed by the rigours of the general conflict; every one for himself is her rule, the safeguard of the future. With maternity and its imperious duties, communism ceases to be practicable. At first sight, certain Hymenoptera [10] seem to declare the contrary. We find, for instance, the Mason-bees of the Sheds [11] nesting in myriads on the same tiles and building a monumental edifice at which all the mothers work. Is this really a community? Not at all. It is a city in which the inhabitants have neighbours, not collaborators. Each mother kneads her pots of honey; each amasses a dowry for her offspring and nothing but a dowry for her offspring; each wears herself out for her family and only for her family. Oh, it would be a serious business if some one merely came and alighted on the brim of a cell that did not belong to her; the mistress of the house would give her to understand, by means of a sound drubbing, that manners such as those are not to be endured! She would have to skedaddle very quickly, unless she wanted a fight. The rights of property are sacred here. Even the much more social Hive-bee is no exception to the rule of maternal egoism. To each hive one mother. If there be two, civil war breaks out and one of them perishes by the other’s dagger or else quits the country, followed by a part of the swarm. Although virtually fit to lay eggs, the other Bees, to the number of some twenty thousand, renounce maternity and vow themselves to celibacy in order to bring up the prodigious family of the one and only mother. Here, communism reigns, under certain aspects; but, for the immense majority, motherhood is forthwith abolished. Even so with the Wasps, the Ants, the Termites [12] and the various social insects. Life in common costs them dear. Thousands and thousands remain incomplete and become the humble auxiliaries of a few who are sexually endowed. But, whenever maternity is the general portion, individualism reappears, as among the Mason-bees, notwithstanding their show of communism.