Ill-defined spiral bands tell us how the Wasp went to work. With her pellet of paper-pulp in her mandibles, she moved downwards in a slanting direction, following the [[228]]margin of the part already constructed and leaving as she went a ribbon of her material, still quite soft and impregnated with saliva. The work was discontinued and resumed hundreds and hundreds of times, for the supply was soon exhausted. The Wasp had to go to some woody stem hard by, a stem retted by the moist air and bleached by the sun, and scrape it with her teeth; she had to tear out its fibres, to divide them, unravel them and work them up into a plastic felt. When the pellet was removed, the Wasp hastened back to resume her interrupted ribbon.
There was even the collaboration of several builders. The foundress of the city, the mother, alone at the outset and absorbed by family cares, was able only to make a rough beginning of the roof; but offspring arrived, neuters,[2] eager assistants henceforth charged with the continuing and enlarging of the dwelling, in order to provide the one mother with a lodging to contain the whole of her eggs. This gang of paper-makers, coming one by one to take part in the labour, or perhaps working without any common agreement, several at a time, at different points, so far from producing [[229]]confusion, achieves perfect regularity. By slow degrees the spacious dome of the summit decreases in diameter; by degrees it tapers into a cone and ends in a graceful neck. Individual and almost independent efforts result in an harmonious whole. Why?
Because these building insects possess an innate geometry, an order of architecture which is known without being taught and which is constant in the same group, while varying as between one group and another. Just as much as the details of the organism, or perhaps even more so, this propensity to build according to certain determined rules characterizes the corporations known by the name of species. The Chalicodoma of the Walls has her earthen tower, the Pelopæus her twisted clay cylinder, the Agenia her urn, the Anthidium her cotton wallet, the Eumenes her open-mouthed cupola and the Wasp her paper balloon. And so with the others: each has her own art.
Our builders contrive and calculate before they set to work. The insect dispenses with these preliminaries; it knows nothing of the hesitations of apprenticeship. From the laying of the first stone it is a past master of its craft. It builds with [[230]]the same accuracy and the same unconsciousness as those displayed by the mollusc, which coils its shell in a scientific spiral; if nothing hinders its aims, it always achieves a graceful and wisely economical structure. But, when a number of cells mutually hamper one another, the regulation plan, without being abandoned, undergoes alterations imposed by lack of space. Massing leads to irregularity. Here, as with us, liberty makes for order and constraint for disorder.
We will now open the nest of the balloon-building Wasp. Here is something that we did not expect. Instead of one envelope there are two, one enclosed within the other, with a slight interval between. There would have been even more, three or four of them, had not impatient hands, eager to bring me the masterpiece, culled it before it reached perfection. The nest is incomplete, as is proved by the single story of cells. A perfect Wasps’-nest would contain several stories.
No matter: such as it is, this work shows us that the chilly Wasp was acquainted with the art of preserving heat before we were. Physics teaches us the efficacy of a cushion of air, motionless between two walls, as a [[231]]preventive against cooling; it recommends the use of double windows to maintain a mild temperature in our houses in winter. Long before the days of human science, the little Wasp, that passionate lover of warmth, knew the secret of multiple envelopes containing layers of air. With its three or four balloons, fitting within one another, her nest, hanging in the sun, must turn into a vapour-bath.
These paper containers are merely defensive works; the actual city, for which all the rest has been built, occupies the top of the dome. It consists at present of a single layer of hexagonal cells, open below. Later on, other, similar layers would have been added, descending in stages and each connected with its predecessor by little papier mâché columns. The aggregate of these layers, or combs, would supply not far short of a hundred cells, the lodgings of as many larvæ.
The method of rearing imposes on the Social Wasps rules unknown to the other builders. These latter store in each cell provisions—honey or game—apportioned to the grub’s needs. The egg once laid, they close the cell. The rest does not concern them: the immured larva will find [[232]]all around it the wherewithal to nourish itself and to thrive without outside help. Under these conditions, the irregular grouping of the cells is of trifling importance; disorder even is admissible, provided that the whole group be in a place of safety, if need be under the cover of a protective casing. Richly supplied with provender and tranquil in its crypt, none of the recluses expects anything from the outer world.
Among the Social Wasps a very different order of things obtains. Here the larvæ, from the beginning to the end of their growth, are incapable of sufficing unto themselves. Like little birds in the nest, they are fed by mouth; like babies in the cradle, they need constant attention. The workers, who are celibates expressly appointed to perform household labours, come and go incessantly, from bed-chamber to bed-chamber; they awaken the sleepy larvæ, wash them with a lick of the tongue and disgorge, from mouth to mouth, the ration of the moment. So long as the larval state continues there is no end to these alimentary kisses between the nurselings gaping with hunger and the nurses returning from the fields, their crops swollen with pap.
Nurseries of this kind, which, in the [[233]]case of various Social Wasps, number their cradles by the thousand, require ease of inspection, quickness of attendance and therefore perfect order. Whereas it makes no difference to the Chalicodomæ, the Eumenes and the Pelopæi whether their cells be grouped without any great precision, since, once provisioned and sealed, they will not be visited again, it is important to the Social Wasps that theirs should be arranged methodically, for otherwise the enormous household, degenerating into a turbulent mob, could not possibly be served.