Let us watch the Wasp as she returns to the burrow with her capture held under her abdomen between her legs. Here comes one, the Tarsal Bembex (B. tarsata), who arrives laden with a Bee-fly. The nest is situated at the sandy foot of a steep bank. The huntress announces her approach by a shrill humming, which has something plaintive about it and which continues until the insect sets foot to earth. We see the Bembex hover above the bank and then dip straight down, very slowly and cautiously, all the time emitting her shrill hum. Should her keen eye descry anything unusual, she slackens her descent, hovers for a second or two, goes up again, comes down again and flies away, swift as an arrow. After a few moments, here she is once more. Hovering at a certain height, she appears to be inspecting the locality, as if from the top of an observatory. The vertical descent is resumed with the most cautious slowness; finally, the Wasp alights with no hesitation whatever at a spot which to my eye has naught to distinguish it from the rest of the sandy surface. At that instant the plaintive whimper ceases. The insect, no doubt, has landed more or less on chance, since the most practised eye cannot distinguish one spot from the other on that expanse of sand; it has alighted somewhere near its home, of which it will now seek the entrance, concealed after its last exit not only by the natural falling-in of the materials but also by the Wasp’s own careful sweeping. But no: the Bembex does not hesitate at all, does not grope about, does not seek. By common consent the antennæ are looked upon as organs for guiding insects in their searches. At this moment of the return to the nest, I see nothing particular in the play of the antennæ. Without once letting go her prey, the Bembex scratches a little in front of her, at the very spot where she has alighted, gives a push with her head and straightway enters, with the Fly under her abdomen. The sand falls in, the door closes and the Wasp is at home.