What can this shutter be which, descending or ascending in the cylinder of the pit, after the fashion of a piston, opens and closes the house at each departure and at each arrival? It is an Halictus, who has become the portress of the establishment. With her large head, she makes an impassable barrier at the top of the entrance-hall. If any one belonging to the house wants to go in or out, she “pulls the cord,” that is to say, she withdraws to a spot where the gallery widens and leaves room for two. The other passes. She then at once returns to the orifice and blocks it with the top of her head. Motionless, ever on the look-out, she does not leave her post save to drive away importunate visitors. Let us profit by her brief appearances outside. We recognize in her an Halictus similar to the others, who are now busy harvesting; but the top of her head is bald and her dress is dingy and threadbare. The handsome striped belts, alternately brown and ruddy-brown, have almost vanished from her half-stripped back. Her old, tattered clothes, well-worn with work, explain the matter clearly. The Bee who mounts guard and performs the office of a portress at the entrance to the burrow is older than the others. She is the foundress of the establishment, the mother of the actual workers, the grandmother of the present grubs. In the spring-time of her life, three months ago, she wore herself out in solitary works. Now that her ovaries are dried up, she takes a well-earned rest. No, rest is hardly the word. She still works, she assists the household to the best of her power. Incapable of being a mother for the second time, she becomes a portress, opens the door to the members of her family and makes strangers keep their distance. The suspicious kid, looking through the chink, said to the wolf: “Show me a white foot, or I shan’t open the door.” No less suspicious, the grandmother says to each comer: “Show me the yellow foot of an Halictus, or you won’t be let in.” None is admitted to the dwelling unless she be recognized as a member of the family. See for yourself. Near the burrow passes an Ant, an unscrupulous adventuress, who would not be sorry to know the meaning of the honeyed fragrance that rises from the bottom of the cellar. “Be off, or mind yourself!” says the portress, with a movement of her neck. As a rule, the threat suffices. The Ant decamps. Should she insist, the watcher leaves her sentry-box, flings herself upon the saucy jade, buffets her and drives her away. The moment the punishment has been administered, she returns on guard and resumes her sentry-go.