We found that the tunnel was thirty-nine centimeters in length. This was a long distance for her to excavate, and, all things considered, her progress had been rapid. We have opened a number of stems that had been stored by this species, and all the excavations were from thirty to forty centimeters in length, the width of the gallery being about three and one half millimeters, while on each side there was from one to one and one half millimeters of pith that had not been cut away. Of course these points varied with the diameter of the stem and also with the size of the worker.
Our little stirpicola had stored one cell, had laid an egg, and had built a partition of pith across the stem as a floor to the second cell, before her untimely taking off. Had she lived, ten or twelve cells would have been stored, one above the other. The completed cell contained a larva and parts of eighteen flies of different sizes, four species being represented. The flies had all been attacked by the larva, the abdomens of some and the thoraces of others having been eaten. The larva continued to eat for two days, and then spun its cocoon. The flies found in this and in other nests of stirpicola were all dead. All the pupæ that we kept wintered in the cocoon and came out in the spring.
AMMOPHILA SLEEPING IN THE GRASS (AFTER BANKS)
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The females of Crabro, like those of other genera, seem to use their galleries as sleeping places, but the males stop at any convenient inn. We once entertained one of them for several nights in a hole in one of the posts of our cottage porch. Other males, as in Philanthus, spend time and care in digging a hole in the ground, to which they return night after night. In Agenia the female keeps one cell ahead of her needs, and tucks herself away in it very comfortably; but the Pelopæi, instead of making this use of their tubes, congregate in the evening where there are convenient crevices, and make as much fuss about getting settled as a lot of English sparrows. Mr. Banks has made a delightfully pretty as well as interesting observation on the sleeping habits of Ammophila. In a corner of his garden where the grass grew long, dozens of these wasps arrived every evening, and after a good many changes in position, fell sound asleep, clinging to the stems about one third of the way down. They registered at this hotel between seven and eight o’clock, and departed before five in the morning. We have seen a Pompilus take the greatest care in selecting a sheltered spot under some leaves, where she afterward hung herself up, and slept soundly until after eight the next day; and Mr. Brues has found companies of Priononyx atrata passing the night on the stems of sweet clover.