Obviously the figures in this table must be regarded as approximate. The number of cells varies greatly in different nests and cannot be calculated very accurately. The counting is correct, in the case of each comb, to a hundred or so. Despite the elasticity of these figures, my result agrees very well with that obtained by Réaumur, who, in a nest of fifteen combs, counted sixteen thousand cells. The master adds:
“With only ten thousand cells, as there is perhaps not a cell which does not, on an average, serve to rear three larvæ, a Wasps’-nest produces over thirty thousand Wasps a year.”
Thirty thousand, say the statistics. What becomes of this multitude when the bad weather arrives? I shall find out. We are now in December; there are occasional frosts, though they are not yet very serious. I know of a nest. I owe it to the man who provides me with Moles, a worthy fellow who, for a few halfpence, makes good the poverty of my vegetable-beds with his own produce. Despite the inconvenience which the proximity caused him, he has preserved the nest for me in his garden, among the [[260]]cauliflowers. I can visit it at any moment that I consider opportune.
The moment has come. Preliminary asphyxiation with petrol is no longer necessary: the cold weather will have calmed the fierce ardour of the inmates. The torpid insects will be pacific enough: with a little caution I shall be able to molest them with impunity. Early in the morning, then, the investing-trench is dug with the spade, amid the grass white with hoar-frost. The work proceeds satisfactorily. Not a Wasp stirs. Here is the nest facing us, hanging from the roof of the cavern.
At the bottom of the crypt, rounded like a basin, lie the dead and dying; I could pick them up by the handful. It looks as though the Wasps, when they feel their strength fail them, leave their dwelling and allow themselves to fall into the catacombs of the burrow. It may even be the duty of the able-bodied ones to cast the dead out of the nest. The paper tabernacle must not be defiled by corpses.
Dead Wasps likewise abound in the open air, on the threshold of the crypt. Did they come to die there of their own accord? Or did the survivors, as a hygienic measure, carry them out of doors? I incline to the [[261]]idea of the summary funeral. The dying insect, still kicking, is seized by one leg and dragged to the Gemoniæ. The night cold will kill it outright. These brutal obsequies tally with other instances of savagery, to which we shall return.
In this double cemetery, inside and outside the burrow, the three classes of the population are represented promiscuously. The neuters are the most numerous; next come the males. That these should disappear is quite natural; their part is played. But the future mothers, the females with flanks rich in eggs, these also perish. Fortunately the Wasps’-nest is not yet entirely deserted. Through a rent I can see a swarm amply sufficient for my plans. We will take the nest away with us and arrange matters for an observation which will last some time and which can be conducted leisurely at home.
The nest will be more convenient to watch if dismembered. Cutting the connecting pillars, I separate the shelves of combs and stack them afresh, giving them a wide fragment of the wrapper as a roof. The Wasps are then re-established in their dwelling, but in limited numbers, to avoid the confusion of a crowd. I keep the more able-bodied and reject the others. The females, the chief [[262]]object of my examination, are not far from a hundred strong. Peaceable now and half-numbed, the population of the nest may safely be subjected to this sifting and shifting. Tweezers are all that I need. The whole nest, installed in a large earthen pan, is covered with a wire-gauze dome. We have only to follow events day by day.
Two factors of decay seem to play a leading part when the Wasps’-nest is depopulated on the advent of the bad weather: hunger and cold. In the winter there is no more provender, no more sweet fruit, the Wasps’ principal food. Lastly, notwithstanding their underground shelter, the frost puts an end to the starved creatures. Is this really what happens? We shall see.
The pan containing the Wasps is in my study, where a fire is lit daily in winter, partly for my benefit and partly for that of my insects. It never freezes there; and the sun shines into the room for the greater part of the day. In this mild retreat the risks of depopulation by cold are eliminated. Nor is there any fear of famine. Under the wire cover is a saucer filled with honey; grape-pips, furnished by my last bunches kept on the straw, vary the diet. With such provisions as these, if any deaths occur among [[263]]the swarm, starvation will not be responsible.