If it ate into its heap of provisions at random, it would expose itself to serious risks from the outside; at the very least it would be liable to slip out of its cradle and tumble to the ground through the open window. Once [[84]]it falls out of its cell, there is no hope for the little grub. It will not know how to make its way back to the larder; and, if it does find its heap of provisions again, it will be repelled by the hard rind with its bits of grit and sand. In its wisdom, greater than any possessed by the young of the higher animals, which are always watched over by a mother, the new-born larva, still sleek and shiny with the slime of the egg, thoroughly knows the danger and avoids it by masterly tactics.
Though all the food around it is alike and all is to its taste, nevertheless it tackles exclusively the floor of its cell, a floor continued by the bulky sphere in which bites will be permissible in every direction, as the consumer pleases.
Can any one explain why this particular spot is chosen as the starting-point, when there is nothing to distinguish it, from the point of view of food? Could the tiny creature be warned of the proximity of the outer air by the effect which a thin wall has on its sensitive skin? If so, how is this effect produced? Besides, what does a grub, that moment born, know of outside dangers? I am quite in the dark.
Or rather I begin to see daylight. I recognize once again, under another aspect, what was taught me some years ago by the Scolia-wasps[1] and the Sphex-wasps,[2] those scientific eaters, those skilful anatomists, who can discriminate so well between the lawful and the unlawful and are consequently able to devour their prey without killing it until the end of the meal. The Sacred Beetle [[85]]has his own complicated art of eating. Though he need not trouble about the preservation of the victuals, which are not liable to go bad, he has nevertheless to guard against ill-timed mouthfuls, which would rob him of his shelter. Of these dangerous mouthfuls, the earliest are the most to be feared, because of the creature’s weakness and the thinness of the wall. As its protection, therefore, the grub has, in its own way, the primal inspiration without which none would be able to live; it obeys the imperious voice of instinct, which says:
‘There shalt thou bite and no elsewhere.’
And, respecting all the rest, however tempting, it bites at the prescribed spot; it eats into the pear at the bottom of the neck. In a few days it has worked its way deep down into the mass, where it waxes big and fat, transforming the filthy material into a plump larva gleaming with health, ivory-white with slate-coloured reflections and without a speck of dirt upon it. The matter which has disappeared, or rather which has been remelted in life’s crucible, leaves empty a round cell into which the grub fits itself, curving its back under the spherical dome and bending double.
The time has come for a sight stranger than any yet displayed to me by the industrial prowess of an insect. Anxious to observe the grub in the intimacy of its home, I open in the belly of the pear a little peep-hole half a centimetre[3] square. The head of the recluse at once appears in the opening, to enquire what is happening. The breach is perceived. The head disappears. I can just see the white back turning about in the narrow cabin; and, then and there, the window which I have made is closed with a soft, brown paste, which soon hardens. [[86]]
The inside of the cabin, said I to myself, is no doubt a semifluid porridge. Turning round, as is shown by the sudden slide of its back, the grub has collected a handful of this material and, completing the circuit, has stuck its load, by way of mortar, in the breach which it considered dangerous. I remove the plug. The grub acts as before, puts its head at the window, withdraws it, spins round as easily as a nut in its shell and forthwith produces a second plug as ample as the first. Forewarned of what was coming, this time I saw more clearly.
What a mistake I had made! However, I am not so much startled as I might be: in the art of defence, animals often employ means which our imagination would not dare to contemplate. It is not the grub’s head that is presented at the breach, after the preliminary twisting: it is the other extremity. It does not bring a lump of its alimentary dough, gathered by scraping the walls: it excretes upon the aperture to be closed, which is a much more economical proceeding. Sparingly measured out, the rations must not be wasted: there is just enough to live upon. Besides, the cement is of better quality; it soon sets. Lastly, the urgent repairs are more quickly effected if the intestines lend their kindly aid.
They do, in point of fact, and to an astonishing degree. Five, six times in succession and oftener, I remove the plug; and, time after time, the mortar ejects a copious discharge from its apparently inexhaustible reservoir, which is ever at the mason’s service, without an interval for rest. The grub is already beginning to resemble the Sacred Beetle, whose stercoraceous prowess we know: it is a past master in the art of dunging. It possesses above any other animal in the world an intestinal docility which anatomy presently will undertake to explain to us in part. [[87]]