_Lasius something_ is the name of the ant which _Antennophorus_ utilises in this way, and it is, I think, a European species. Another one—_Pachycondyla harpax_—the large, black ant of America—wears its parasite round its neck, like an Elizabethan ruff. In this case both host and guest are in the larval state, and the involuntary partnership between them—involuntary probably on the part of either—is not dissolved until both have attained full maturity. The position of affairs is this: the ant larva apparently lies on its back upon earth a little hollowed, to receive it, by the workers of the nest. The parasitic larva—that of an unknown species of fly—has a long, slender neck, as we may call the anterior part of the body, and whilst this is wound about the corresponding portion of its host, the body, which broadens out after the manner of an oil-flask, is affixed by a disc at its end to some part of the back of the latter. When the ants feed the larvæ, they place the food—which consists either of grain that has been stored, or of insects captured and torn up by them—on the broad surface of the abdomen, which forms a sort of trough for its reception. Immediately upon feeling the welcome load, the hungry larva stretches down its head to the banquet, but that of the parasite moves with it, and its small, sharp jaws take eager toll of each dish. Thus the two feed together, cheek by jowl, and should what has been provided prove insufficient for this double onslaught, the unbidden guest will stretch its snake-like neck, and move it ceaselessly until the ever-ready jaws come into contact with a second feast, upon the table next it. Should none, however, be within reach, the guest will give vent to its irritated feelings by biting the bodies of such unbounteous Timons, or even that of its own host. They wriggle with pain, and this may possibly induce the ants to bring them fresh supplies, under the impression that they are hungry, as indeed they may be, with meals shared in this way. If so, we can hardly suppose a parasitic larva to act with such a motive, but as the best biters would in this case get the most food, natural selection may possibly have helped to develop the habit, which would have a compensating advantage for the wrigglers too. As the French say, “_Il y a compensation en tout._”