For a good quarter of an hour, the captive clambers up the sides of the bell-glass, crawls down again and up again, seeking an outlet whereby to escape, and seems to pay no attention to the game. I was already despairing of success when suddenly the huntress falls upon the larva, turns it over, belly upwards, clasps it and stings it thrice in succession in the thorax, particularly under the neck, in the median region, a point at which the sting is more insistent than elsewhere. The close-clasped larva does its utmost to protest, emptying its scent-bottles and oiling itself with petrol; but these defensive tactics have no effect. Indifferent to the heady perfume, the Odynerus performs her operation, wielding her lancet with the same certainty as if the patient were scentless. Thrice the sting is driven in, to kill the motor nerves in the three ganglia of the thorax. I repeat the experiment with other subjects. Few refuse to attack the prey; and each time three stings are administered with marked insistence at the point under the neck. What I saw under artificial conditions Claire, on her side, saw under conditions of liberty, in the open air, on the leaves of the transplanted poplar. The two collaborators, she and I, arrived at precisely the same result. The operation is rapidly performed. Then the Odynerus, while dragging her prey along, belly to belly, munches at its neck for a considerable time, but without causing any wound. This action may well be equivalent to the practice of the Languedocian Sphex and the Hairy Ammophila, [61] when, without inflicting a bruise, the one nibbles at the neck of her Ephippiger and the other at that of her Grey Worm, in order to compress and paralyse the cervical ganglia. I of course take possession of the torpid larvæ. The victim is absolutely inert, save for a slight quivering of the legs, which soon ceases. When laid upon its back, the larva no longer stirs. It is not dead, however; that I have been able to prove. Its dull vitality is affirmed in another manner. During the first few days of this lethargy which knows no awakening, droppings are ejected until the intestine is empty. On renewing my experiments, I witness something so singular that I am at first baffled. This time the prey is seized by the anal extremity and the sting is driven several times into the last segments, underneath the abdomen. This is the usual operation reversed and performed upon the hinder segments, instead of those of the thorax. The surgeon and the patient, who are head to head in the normal method, are in the present instance head to tail. Can it be by inadvertence that the operator is confusing the two ends of the grub and stinging the tip of the abdomen under the impression that she is stinging the neck? I believe it for a moment, but am soon undeceived. Instinct does not make mistakes of this sort.