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.
When the weather was cold and cloudy punctatus remained closely housed within the nest, or, at most, came out to do an hour’s digging, and then disappeared. The warmer the weather, and the more brilliant the sunshine, the more rapidly they worked. When leaving the nest they would often creep out and walk around it three or four times before rising on their wings, and even then would sometimes alight once or twice before flying away. The males, especially, liked to stand about for a time, watching their more industrious sisters at their work. The females usually began the day with digging, and frequently closed it, toward night, in the same way.
In order to see the method of stinging, we at one time provided ourselves with a number of bees, and putting one of them into a bottle, introduced a wasp. She seized it almost immediately, with great vigor, and stung it once, under the neck, and then dragged it up and down the bottle by one antenna which was held in the mandibles. After a moment she shifted it and held it with the second legs in the usual way. We now put in another bee, which she also caught, stung in the same place, and then dropped without relaxing her hold of the first one. As she seemed to have nothing further to show us we released her, and after circling a little she took into her nest the bee that she was carrying.
In our next experiment we used a larger glass, thinking that with more space we might see malaxation. The instant that the wasp was introduced she grasped the bee with one rapid powerful motion, and stung it just under the neck as before. Then holding it with the second legs she began to fly about in the glass. We now introduced another bee, whereupon the first one was relinquished, and the second was treated in exactly the same way. The stinging was the beginning and the end of the operation, and when we released her she at once took the bee into the nest. There was no malaxation outside, and certainly there was none within, as was shown by the rapidity with which the wasps issued from the nest after storing the bees. We were successful in getting the wasps to sting only when we tried the experiment with those that were hunting. When those that had not yet begun to store their nests were put into the glass they paid no attention to the bees.
The victim of the sting of punctatus is killed at once. Life is extinct from the instant that the stroke is given. This is true also of the honey-bee that is the victim of Fabre’s Philanthus apivorus; but the explanation that he gives of the action of his wasp in thus dealing sudden death instead of paralyzing its foe—that the honey must be sucked out of the bee before it can be safely used as food for the larva—does not hold good in our case, since the honey that Halictus carries to mix with the pollen upon which her offspring are fed, is not removed.
NEST OF PHILANTHUS PUNCTATUS
A-B, 3½ inches; B-C, 5 inches; C-D, 14 inches; D-E, 8 inches