Two hours elapse, exhausting my patience. I make arrangements with my household. Three of us will relieve one another in turn, keeping an uninterrupted watch on the obstinate creature, whose secret I must have at all costs.
I was well-advised to call in helpers to lend me their eyes and their attention. After eight hours, eight endless hours, the sentry on the watch summons me. The insect appears to have finished. It does in fact step back, it withdraws its drill, [[79]]carefully, lest it should bend it. The tool is now outside, once more pointing forwards, in a straight line.
This is the moment.… Alas, no! Once again I am cheated: my eight hours’ watch has led to nothing. The Weevil decamps, abandons the acorn without making use of her boring. Yes, I was certainly right to distrust observation in the woods. Such a period of waiting among the ilexes, under the scorching sun, would have been an unbearable torture.
All through October, with the aid of helpers when needful, I remark numerous borings not followed by any laying. The operation varies greatly in length. Generally it lasts a couple of hours; sometimes it takes half the day or even more.
What is the object of these shafts, made at such cost of time and labour and very often left unstocked? Let us first look for the site occupied by the egg and forming the grub’s earliest mouthfuls; then perhaps the reply will come.
The inhabited acorns remain on the oak, encased in their cups as though nothing abnormal were happening to injure the seed-lobes. They are easily recognized with a little attention. Not far from the cup, on the smooth and still green shells, a little speck shows, just like the prick of a fine needle. Soon it is surrounded by a narrow brown ring, the result of mortification. This is [[80]]the mouth of the hole. At other times, but less often, the opening is made through the cup itself.
We will take the acorns recently perforated, that is to say, those with a pale puncture, not yet surrounded by the brown ring which will appear in time. Shell them. Several contain no foreign matter: the Weevil has bored them without laying her eggs in them. These represent the acorns worked for hours and hours in my cages and not afterwards used. Many contain an egg.
Now, however far above the cup the entrance to the pit may be, this egg is always right at the bottom, at the base of the seed-lobes. There is here, provided by the cup, a soft, blanket-like layer which imbibes the sapid exudations from the tip of the peduncle, the source of nourishment. I see a young grub, hatched before my eyes, nibble as its first mouthfuls this tender woolly mass, this moist cake flavoured with tannin.
This dainty, juicy and easy of digestion, like all nascent organic matter, is found only at this particular spot; and it is solely here, between the cup and the base of the seed-lobes, that the Weevil lodges her egg. The insect knows to a nicety the position of the morsels best-suited to the feeble stomach of the new-born larva.
Above this is the comparatively coarse bread of the seed-lobes. Refreshed by its first meal at the drinking-bar, the grub enters it, not directly, but through the tunnel opened by the mother’s [[81]]probe, a tunnel littered with crumbs, with half-masticated fragments. This light farinaceous food, prepared in a column of appropriate height, gives strength; and the grub next penetrates right into the firm substance of the acorn.