3. The operator grips the caterpillar by the skin of the back, a little lower than before, and pricks the second segment, still on the ventral surface. I then see her gradually recoiling along the Grey Worm, each time seizing the back a little lower down, clasping it with the mandibles, those wide pincers with the curved jaws, and each time driving the sting into the next segment. This recoil of the insect and this gradual clasping of the back, a little farther down on each occasion, are effected with methodical precision, as though the huntress were measuring her prey. At each step backward the dart stings the following segment. In this way are wounded the three thoracic segments, with the true legs; the next two segments, which are legless; and the four segments with the pro-legs. In all, nine stings. The last four segments are disregarded: they consist of three without legs and the last, or thirteenth, with pro-legs. The operation is accomplished without serious difficulty: after the first prick of the needle, the Grey Worm offers but a feeble resistance. 4. Lastly, the Ammophila, opening the forceps of her mandibles to their full width, seizes the caterpillar’s head and crunches it, squeezes it with a series of leisurely movements, without creating a wound. These squeezings follow upon one another with deliberate slowness: the insect seems to try each time to learn the effect produced; it stops, waits, and then resumes the attack. This manipulation of the brain, to attain the desired end, must have certain limits which, if exceeded, would bring about death and speedy putrefaction. And so the Wasp regulates the force of her compressions, which, moreover, are numerous: about a score, in all. The surgeon has finished. The patient lies on the ground on its side, half doubled up. It is motionless, lifeless, incapable of resistance during the traction-process that is to bring it home, unable to harm the grub that is to feed upon it. The Ammophila leaves it at the place where the operation was performed and goes back to her nest. I follow her. She makes certain improvements in view of the coming storage. A pebble projecting from the roof might impede the warehousing of the bulky quarry. The lump is forthwith removed. A rustle of grazed wings accompanies the arduous task. The back-room is not large enough: it is widened. The work is long-drawn-out; and the caterpillar, which I have neglected to watch, lest I should miss any of the Wasp’s doings, is invaded by the Ants. When the Ammophila and I return to it, it is black all over with busy carvers. This is a regrettable incident for me and a grievous event for the Ammophila; for it is the second time that she has met with the same mishap.