In the end, another idea occurred to me and made me doubt whether my rebuffs were always due to clumsy accidents. The Eumenes' cells are crammed with game: there are ten caterpillars in the cell of Eumenes Amedei and fifteen in that of Eumenes pomiformis. These caterpillars, stabbed no doubt, but in a manner unknown to me, are not entirely motionless. The mandibles seize upon what is presented to them, the body buckles and unbuckles, the hinder half lashes out briskly when stirred with the point of a needle. At what spot is the egg laid amid that swarming mass, where thirty mandibles can make a hole in it, where a hundred and twenty pairs of legs can tear it? When the victuals consist of a single head of game, these perils do not exist; and the egg is laid on the victim not at hazard, but upon a judiciously chosen spot. Thus, for instance, Ammophila hirsuta fixes hers, by one end, cross-wise, on the Grey Worm, on the side of the first prolegged segment. The eggs hang over the caterpillar's back, away from the legs, whose proximity might be dangerous. The worm, moreover, stung in the greater number of its nerve-centres, lies on one side, motionless and incapable of bodily contortions or said an jerks of its hinder segments. If the mandibles try to snap, if the legs give a kick or two, they find nothing in front of them: the Ammophila's egg is at the opposite side. The tiny grub is thus able, as soon as it hatches, to dig into the giant's belly in full security. How different are the conditions in the Eumenes' cell. The caterpillars are imperfectly paralysed, perhaps because they have received but a single stab; they toss about when touched with a pin; they are bound to wriggle when bitten by the larva. If the egg is laid on one of them, the first morsel will, I admit, be consumed without danger, on condition that the point of attack be wisely chosen; but there remain others which are not deprived of every means of defence. Let a movement take place in the mass; and the egg, shifted from the upper layer, will tumble into a pitfall of legs and mandibles. The least thing is enough to jeopardize its existence; and this least thing has every chance of being brought about in the disordered heap of caterpillars. The egg, a tiny cylinder, transparent as crystal, is extremely delicate: a touch withers it, the least pressure crushes it.