To facilitate my inspection, I separate the combs and place them side by side, with the openings of the cells turned upwards. This arrangement, which reverses the normal, does not appear to annoy my captives, who, soon recovering from their disturbance, set to work as if nothing unusual had occurred. In case they should wish to build, I give them a slip of soft wood to draw upon. Lastly, I feed them with honey, poured into a pool on a strip of paper and renewed daily. The underground cavern is represented by a large earthen pan surmounted by a wire-gauze cover. A cardboard dome, placed over the cover or removed at will, provides alternately the obscurity demanded by the Wasps’ labours and the light needed for my observations. The work is continued from one day to another. The Wasps attend at the same time to the larvæ and to the house. The builders begin to erect a wall round the most thickly-colonized combs. Do they intend to repair the disaster and build a new envelope, which will replace the vanished enclosing wall? The progress of the operation seems to tell us no. They are simply continuing the work which my terrible flask and my spade have interrupted. Over an area embracing hardly a third of the comb, they erect an arched roof of paper scales which would have been joined to the envelope of the nest had it been intact. They are not beginning again; they are continuing. In any case, the sort of tent thus obtained shelters but a small part of the disk of cells. This is not for lack of materials. To begin with, there is the slip of wood, providing, in my opinion, an excellent supply of fibrous scraps. But the Wasps do not touch it. Perhaps I have chosen the wrong sort of piece, being but ill-versed in the secrets of Vespian paper-making. To these raw materials, which are troublesome to work, they prefer the old cells, now fallen into disuse. In these the felted fibres are ready prepared and have only to be reduced to pulp again. With a slight expenditure of saliva and a little grinding in the mandibles, it yields a product of the highest quality. The uninhabited cells, therefore, are demolished by degrees, nibbled and razed to their foundations. Out of the ruins a sort of canopy is built. New cells would be constructed in the same way if they were needed. This confirms what the upper stories with demolished cells made us foresee: the Wasps build new cells with old. The feeding of the grubs deserves examination even more than this roofing-work. One would never weary of the spectacle of these rough fighters converted into tender nurses. The barracks are turned into a crèche. What care, what vigilance in the rearing of the grubs! Let us watch one of the busy Wasps. Her crop swollen with honey, she halts in front of a cell; almost pensively she bends her head into the orifice; she questions the recluse with the tip of her antenna. The larva wakes and gapes at her, like the fledgeling when the mother-bird returns to the nest with food.