At fifteen minutes after ten the worker from nest No. 1 brought in a bee, and from that time the two worked industriously. They showed some individuality in their ways, for No. 2 always closed her door when she went away, and never circled at all, while No. 1 invariably circled before leaving, and always left her nest open. To be sure, there was a female left on guard, so that perhaps she did not feel the need of caution.
Our wasps had not far to go for their victims. Forty feet away, on the eastern side of the island, was a steep declivity, and here, in the soft crumbly soil, was a great Halictus settlement. No prettier sight can be imagined than is presented by this colony on every sunny summer day. The whole bank is riddled with nests, and at the entrance of each stands a female bee, her tiny head exactly filling the opening. The bees are constantly arriving, laden with pollen, whereupon the sentinels politely back inward to make way for them. Into this scene of contented industry descends the ravaging Philanthus, taking guards and workers alike.
On the afternoon of the fourteenth of August our two wasps were in the full tide of affairs. No. 1 took in eleven bees within two hours, but her record was somewhat confused, as two other females were going in and out at the same time. We felt sure that neither of these was hunting, but one of them shared in the labor of the nest by helping with the work of excavation.
No. 2, however, was alone, so that we could keep a definite account of her comings and goings. We watched her from half past one until five, at which hour she came home without a load, and at once closed the nest for the night, after having stored thirteen bees in three hours and nine minutes. In some cases the capture of the bee occupied only one, two, or three minutes, while at other times she was gone much longer. At each return she stayed only an instant—just long enough to deposit the bee—inside the nest, and then spent a minute in carefully closing the hole. The wasps that were going in and out of nest No. 1 sometimes closed it when they went away, but this was done in an untidy fashion, quite different from the nicety and precision of No. 2.
At half after five o’clock the wasp that had been digging for some little time at nest No. 1 flew to nest No. 2, opened it, and attempted to enter, but was quickly driven out by the owner. She then dug a little in several other places, finally returning to sleep in the family home. On the next day we found that No. 2 was tolerating in her nest one of the females that had not yet begun to hunt, but whether it was the one she had rejected the night before or the fourth member of the sisterhood, we could not tell. On the eighteenth, three days later, the wasp had left this temporary home and made a nest for herself four feet away on the hillside. The males were still living in the first nest with two females.