The victim, lying on its back, cannot escape by using its hind levers, for want of anything to spring from, as of course it would were it attacked in its normal position, as are the big Weevils by Cerceris tuberculata. Its spiny legs, mastered by the forefeet of the Sphex, cannot be used as offensive weapons, and its mandibles, held at a distance by the hind-feet of the Hymenopteron, open threateningly but can seize nothing. But it is not enough for the Sphex to render it impossible for her victim to hurt her: she must hold it so firmly garrotted that no movement can turn the sting from the points where the drop of poison must be instilled, and probably it is in order to hinder any motion of the abdomen that one of the end segments is grasped. If a fertile imagination had had free play to invent a plan of attack it could not have devised anything better, and it is questionable whether the athletes of the classic palestra when grappling an adversary would have assumed attitudes more scientifically calculated. I have just said that the dart is plunged several times into the victim’s body, once under the neck, then behind the prothorax, lastly near the top of the abdomen. It is in this triple blow that the infallibility, the infused science of instinct, appear in all their magnificence. First let us recall the chief conclusions to which the preceding study of the Cerceris have led us. The victims of Hymenoptera whose larva live on prey are not corpses, in spite of entire immobility. There is merely total or partial paralysis, and more or less annihilation of animal life, but vegetative life—that of the nutritive organs—lasts a long while yet, and preserves from decomposition the prey which the larvæ are not to devour for a considerable time. To produce this paralysis the predatory Hymenoptera use just those methods which the advanced science of our day might suggest to the experimental physiologist—namely, wounding, by means of a poisoned dart, those nervous centres which animate the organs of locomotion. We know too that the various centres or ganglia of the nervous chain in articulate animals act to a certain degree independently, so that injury to one only causes, at all events immediately, paralysis of the corresponding segment, and this in proportion as the ganglia are more widely separated and distant from each other. If, on the contrary, they are soldered together, injury to the common centre causes paralysis of all the segments where its ramifications spread. This is the case with Buprestids and Weevils, which the Cerceris paralyses by a single sting, directed at the common mass of the nerve centres in the thorax. But open a cricket, and what do we find to animate the three pairs of feet? We find what the Sphex knew long before the anatomist, three nerve centres far apart. Thence the fine logic of the three stabs. Proud science! humble thyself.