Another and still more eloquent fact will finally convince whoso may yet be doubting. The ration of honey stored up in a cell is evidently measured by the needs of the coming larva. There is neither too much nor too little. How does the Bee know when the proper quantity is reached? The cells are more or less constant in dimension, but they are not filled completely, only to about two-thirds of their height. A large space is therefore left empty; and the victualler has to judge of the moment when the surface of the mess has attained the right level. The honey being perfectly opaque, its depth is not apparent. I have to use a sounding-rod when I want to gauge the contents of the jar; and I find, on the average, that the honey reaches a depth of ten millimetres. (.39 inch.—Translator's Note.) The Bee has not this resource; she has sight, which may enable her to estimate the full section from the empty section. This presupposes the possession of a somewhat geometric eye, capable of measuring the third of a distance. If the insect did it by Euclid, that would be very brilliant of it. What a magnificent proof in favour of its little intellect: a Chalicodoma with a geometrician's eye, able to divide a straight line into three equal parts! This is worth looking into seriously.
I take five cells, which are only partly provisioned, and empty them of their honey with a wad of cotton held in my forceps. From time to time, as the Bee brings new provisions, I repeat the cleansing-process, sometimes clearing out the cell entirely, sometimes leaving a thin layer at the bottom. I do not observe any pronounced hesitation on the part of my plundered victims, even though they surprise me at the moment when I am draining the jar; they continue their work with quiet industry. Sometimes, two or three threads of cotton remain clinging to the walls of the cells: the Bees remove them carefully and dart away to a distance, as usual, to get rid of them. At last, a little sooner or a little later, the egg is laid and the lid fastened on.
I break open the five closed cells. In one, the egg has been laid on three millimetres of honey (.117 inch.—Translator's Note.); in two, on one millimetre (.039 inch.—Translator's Note.); and, in the two others, it is placed on the side of the receptacle drained of all its contents, or, to be more accurate, having only the glaze, the varnish left by the friction of the honey-covered cotton.
The inference is obvious: the Bee does not judge of the quantity of honey by the elevation of the surface; she does not reason like a geometrician, she does not reason at all. She accumulates so long as she feels within her the secret impulse that prompts her to go on collecting until the victualling is completed; she ceases to accumulate when that impulse is satisfied, irrespective of the result, which in this case happens to be worthless. No mental faculty, assisted by sight, informs her when she has enough, or when she has too little. An instinctive predisposition is her only guide, an infallible guide under normal conditions, but hopelessly lost when subjected to the wiles of the experimenter. Had the Bee the least glimmer of reason would she lay her egg on the third, on the tenth part of the necessary provender? Would she lay it in an empty cell? Would she be guilty of such inconceivable maternal aberration as to leave her nurseling without nourishment? I have told the story; let the reader decide.
This instinctive predisposition, which does not leave the insect free to act and, through that very fact, saves it from error, bursts forth under yet another aspect. Let us grant the Bee as much judgment as you please. Thus endowed, will she be capable of meting out the future's larva's portion? By no means. The Bee does not know what that portion is. There is nothing to tell the materfamilias; and yet, at her first attempt, she fills the honey-pot to the requisite depth. True, in her childhood she received a similar ration, but she consumed it in the darkness of a cell; and besides, as a grub, she was blind. Sight was not her informant: it did not tell her the quantity of the provisions. Did memory, the memory of the stomach that once digested them? But digestion took place a year ago; and since that distant epoch, the nurseling, now an adult insect, has changed its shape, its dwelling, its mode of life. It was a grub; it is a Bee. Does the actual insect remember that childhood's meal? No more than we remember the sups of milk drawn from our mother's breast. The Bee, therefore, knows nothing of the quantity of provisions needed by her larva, whether from memory, from example or from acquired experience. Then what guides her when she makes her estimate with such precision? Judgment and sight would leave the mother greatly perplexed, liable to provide too much or not enough. To instruct her beyond the possibility of a mistake demands a special tendency, an unconscious impulse, an instinct, an inward voice that dictates the measure to be apportioned.
CHAPTER 8. PARASITES.
In August or September, let us go into some gorge with bare and sun-scorched sides. When we find a slope well-baked by the summer heat, a quiet corner with the temperature of an oven, we will call a halt: there is a fine harvest to be gathered there. This tropical land is the native soil of a host of Wasps and Bees, some of them busily piling the household provisions in underground warehouses: here a stack of Weevils, Locusts or Spiders, there a whole assortment of Flies, Bees, Mantes or Caterpillars, while others are storing up honey in membranous wallets or clay pots, or else in cottony bags or urns made with the punched-out disks of leaves.
With the industrious folk who go quietly about their business, the labourers, masons, foragers, warehousers, mingles the parasitic tribe, the prowlers hurrying from one home to the next, lying in wait at the doors, watching for a favourable opportunity to settle their family at the expense of others.
A heart-rending struggle, in truth, is that which rules the insect world and in a measure our own world too. No sooner has a worker, by dint of exhausting labour, amassed a fortune for his children than the non-producers come hastening up to contend for its possession. To one who amasses there are sometimes five, six or more bent upon his ruin; and often it ends not merely in robbery but in black murder. The worker's family, the object of so much care, for whom that home was built and those provisions stored, succumb, devoured by the intruders, directly the little bodies have acquired the soft roundness of youth. Shut up in a cell that is closed on every side, protected by its silken covering, the grub, once its victuals are consumed, sinks into a profound slumber, during which the organic changes needed for the future transformation take place. For this new hatching, which is to turn a grub into a Bee, for this general remodelling, the delicacy of which demands absolute repose, all the precautions that make for safety have been taken.