Page:Popular Science Monthly Volume 61.djvu/352

346 nest was replaced by one that was finished, went on building until it was half again as high as it should have been. In Polistes it seems that the very success with which these first unfoldings of the feeding instinct meet, serves to stamp it into a useful habit. If the worker is at home, with the feeding larvæ at hand to seize the proffered bit, all goes well, and it becomes henceforth an efficient member of its community. But remove it, and so interfere with the normal unfolding of the reaction, and the wasp soon disregards the food altogether or contents itself with a few perfunctory turns and squeezes.

Not that the wasp has any idea of performing a service for the benefit of its kind. I have seen a young neuter gnaw a piece out of the side of a dead wasp larva fallen from its cell, and turning, offer it as food to the mouth of the self same larva. More than this, I once observed a neuter attack a live larva and, after she had cut out and crushed a fair-sized piece of its body, come back eight times in the course of her examination of the cells of the nest to this larva, which had naturally died in the operation, and offer it this part of its own body with the evident expectation that it would be seized and eaten. The eighth time she dropped the piece on the face of the dead larva and went away with an air of 'duty well done' which was comical to behold. There can be little doubt that the normal repetition of the reflex perfects it, so that finally the process is quicker and easier than at first; and in this sense the little worker learns, but thus far I have had no evidence that it gains anything by the example of its elders.

One other note on the feeding habit may be of interest. Throughout the social Hymenoptera the male is the drone of the colony and usually among the solitary wasps the work of excavating or otherwise constructing and storing the nest devolves entirely on the female. Mr. and Mrs. Peckham recount cases of cooperation of the male with the female of Trypoxylon to the extent of guarding the nest and even taking the spiders as they were brought by the female and packing them properly away. In one colony under observation this fall, the males eagerly took portions of dead larvæ from one another, and crushed and turned them in their mandibles; and, in one instance, when the malaxation was complete, one of them carried it over the nest in the same searching manner as the female, and finally fed it to a larva. This is the only recorded instance among the Vespidæ known to me, but it is likely further careful observations would show similar aberrations of instinct.

Several days usually elapse before the young Polistes makes its first essay into the world. When it does appear, the impulse to fly is strong, though in most cases it soon spends itself. That is, if in captivity, the wasp will repeatedly beat itself against its prison walls and steadfastly