Things are different with a corpse. The tension is relaxed, the muscles become slack, the resistance of the stomach ceases and the bag of honey is emptied by the robber's vigorous pressure. You see, therefore, that the Philanthus is expressly obliged to inflict a sudden death, which will do away at once with the elasticity of the organs. Where is the lightning stroke to be delivered? The slayer knows better than we do, when she sticks the Bee under the chin. The cerebral ganglia are reached through the little hole in the neck and death ensues immediately.
The relation of these acts of brigandage cannot satisfy my distressing habit of following each reply obtained with a fresh question, until the granite wall of the unknowable rises before me. If the Philanthus is an expert in killing Bees and emptying crops swollen with honey, this cannot be merely an alimentary resource, especially when, in common with the others, she has the banqueting-hall of the flowers. I cannot accept her atrocious talent as inspired merely by the craving for a feast obtained at the expense of an empty stomach. Something certainly escapes us: the why and wherefore of that crop drained dry. A creditable motive may lie hidden behind the horrors which I have related. What is it?
Any one can understand the vagueness of the observer's mind when he first asks himself this question. The reader is entitled to be treated with consideration. I will spare him the recital of my suspicions, my gropings and my failures and will come straight to the results of my long investigation. Everything has its harmonious reason for existence. I am too fully persuaded of this to believe that the Philanthus pursues her habit of profaning corpses solely to satisfy her greed. What does the emptied crop portend? May it not be that...? Why, yes.... After all, who knows?... Let us try along these lines.
The mother's first care is the welfare of the family. So far, we have seen the Philanthus hunting only for her stomach's sake; let us watch her hunting as a mother. Nothing is easier than to distinguish the two performances. When the Wasp wants a few good mouthfuls and nothing more, she scornfully abandons the Bee after picking her crop. The Bee is to her a worthless remnant, which will shrivel where it lies and be dissected by the Ants. If, on the other hand, she wants to stow away the Bee as a provision for her larvae, she clasps her in her two intermediate legs and, walking on the other four, goes round and round the edge of the bell-glass, seeking for an outlet through which to fly off with her prey. When she recognizes the circular track as impossible, she climbs up the sides, this time holding the Bee by the antennae with her mandibles and clinging to the polished and perpendicular surface with her six feet. She reaches the top of the glass, stays for a little while in the hollow of the knob at the top, returns to the ground, resumes her circling and her climbing and does not decide to relinquish her Bee until she has stubbornly attempted every means of escape. This persistence on her part to retain her hold on the cumbrous burden tells us pretty plainly that the game would go straight to the cells if the Philanthus had her liberty.
Well, these Bees intended for the larvae are stung under the chin like the others; they are real corpses; they are manipulated, squeezed, drained of their honey exactly as the others are. In all these respects, there is no difference between the hunt conducted to provide food for the larvae and the hunt conducted merely to gratify the mother's appetite.
As the worries of captivity might well be the cause of a few anomalies in the insect's actions, I felt that I ought to enquire how things happen in the open. I lay in wait near some colonies of Philanthi, for longer perhaps than the question deserved, as it had already been settled by what had happened under glass. My tedious watches were rewarded from time to time. Most of the huntresses returned home immediately, with the Bee under their abdomen; some halted on the brambles hard by; and here I saw them squeezing the dead Bee and making her disgorge the honey, which was greedily lapped up. After these preliminaries the corpse was stored. Every doubt is therefore removed: the provisions of the larva are first carefully drained of their honey.
Since we are on the spot, let us prolong our stay and enquire into the customs of the Philanthus in a state of liberty. Serving dead prey, which goes bad in a few days, the Bee-huntress cannot adopt the method of certain insects which paralyse a number of separate heads of game and fill the cell with provisions, completing the ration before laying the egg. She needs the method of the Bembex, whose larva receives the necessary nourishment at intervals, as it grows larger. The facts confirm this deduction. Just now I described as tedious my watches near the colonies of the Philanthi. They were tedious in fact, even more so perhaps than those which the Bembeces used to inflict upon me in the old days. Outside the burrows of the Great Cerceris and other Weevil-lovers, outside those of the Yellow-winged Sphex, the Cricket-slayer, there is plenty of distraction, thanks to the bustling movement of the hamlet. The mother has hardly come back home before she goes out again, soon returning laden with a new prey and once more setting out upon the chase. The going and coming is repeated at close intervals until the warehouse is full.
The burrow of the Philanthus is far from showing any such animation, even in a populous colony. In vain were my watches prolonged for whole mornings or afternoons; it was but very rarely that the mother whom I had seen go in with a Bee came out again for a second expedition. Two captures at most by the same huntress was all that I was able to see during my long vigils. Feeding from day to day involves this deliberation. Once the family is supplied with a sufficient ration for the moment, the mother suspends her hunting-trips until further need arises and occupies herself with mining-work in her underground house. Cells are dug; I see the rubbish gradually pushed up to the surface. Beyond this there is not a sign of activity; it is as though the burrow were deserted.
The inspection of the site is no easy matter. The shaft descends to a depth of nearly three feet in a compact soil, either vertically or horizontally. The spade and pick, wielded by stronger but less expert hands than mine, are indispensable, for which reason the process of excavation is far from satisfying me fully. At the end of this long tunnel, which the straw which I use for sounding despairs of ever reaching, the cells are at last encountered, oval cavities with a horizontal major axis. Their number and general arrangement escape me.
Some of them already contain the cocoon, which is slender and semitransparent, like those of the Cerceris, and, like them, suggests the shape of certain homoeopathic phials, with oval bellies surmounted by a tapering neck. The cocoon is fastened to the end of the cell by the tip of this neck, which is darkened and hardened by the larva's excrement; it has no other support. It looks like a short club fixed by the end of the handle along the horizontal axis of the nest. Other cells contain the larva in a more or less advanced stage. The grub is munching the last morsel served to it, with the scraps of the victuals already consumed lying around it. Others lastly show me a Bee, one only, still untouched and bearing an egg laid on her breast. This is the first partial ration; the others will come as and when the grub grows larger. My anticipations are thus confirmed: following the example of the Bembeces, the Fly-killers, the Philanthus, the Bee-killer, lays her egg on the first piece warehoused and at intervals adds to her nurselings' repast.