We kept these wasps under close observation, often watching the nest from the moment it was opened in the morning until it was closed at night. On the twelfth of August, a week from the time that we first saw them, one of the females felt the responsibilities of life settling down upon her. At half after four in the afternoon she began to enlarge the nest, and worked with a great deal of energy for forty minutes. After a long disappearance within the hole she would come up backwards, kicking behind her a quantity of earth which was not only taken outside, but was then spread out far and wide. She worked with the front pair of legs, which were curved inward, after the manner of Bembex; and when a pebble or some such object came in her way she either dragged it to a distance with her mandibles or pushed it before her with her head in a way quite peculiar to herself. In distributing the earth that was taken out, she went five and one half inches from the nest—a distance which is much greater than is common among wasps, but which accords well with the habits of punctatus, since she continues the work of excavation from day to day.
On August thirteenth, at half after eight in the morning, we found that a second female, perhaps inspired by the example of her sister, had made a new nest within two inches of the first one, and had flown away, leaving it open. Presently the other wasps began to appear, one after the other, in their doorway. Two of the males flew away, and one of the females, doubtless the one that we had seen digging the night before, began to work afresh at making the nest larger. Probably she was excavating a pocket for the reception of an egg, and the amount of labor required was enormously increased by the great length (about twenty–two inches) of the main gallery by which the displaced earth must be carried out. She worked for an hour, and in spreading the dirt about, inadvertently filled in the opening of the second nest. At length she flew away.
At ten o’clock a female arrived carrying a bee, and tried to find nest No. 2. She came to the wrong place, and worked about, here and there, for some minutes, holding the bee under the thorax, clasped by the second pair of legs. Being unsuccessful, she dropped her burden, and flew away for a few minutes. While she was gone we removed a leaf that had fallen over her nest, and on her return she at once descended upon the right spot, and began to scratch open the entrance, the bee being kicked backward with the rejected earth. When the way was clear, however, she picked it up, brought it toward the hole, dropped it, ran in and out, brought it nearer, ran in again, and turning around in the tunnel, seized the bee in her mandibles and pulled it down. This performance was due to the accidental obstruction of the gallery, for we afterward found that punctatus ordinarily flies directly into her nest, or, when it is closed, pauses on the wing to scratch an opening with the first legs. The bee is pushed backward a little as she goes in, but does not often project from under her abdomen.