[Illustration: THOROUGH LOCALITY STUDY BY SPHEX]
As the afternoon wore on she worked more calmly and her fidgety and excited manner disappeared, the excavation progressing steadily until half–past three. At that time she came out and walked slowly about in front of her nest and all around it. Then she rose and circled just above it, gradually widening her flight, now going further afield and now flying in and out among the plants and bushes in the immediate vicinity. The detailed survey of every little object near her nest was remarkable; and not until her tour of observation had carried her five times entirely around the spot did she appear satisfied and fly away. All her actions showed that she was studying the locality and getting her bearings before taking her departure. A fact that impressed us very much was that with the two nests that she had begun and then deserted she had taken no such precaution, but simply came up and flew off. Had she made up her mind, if we may be allowed to use the term, that the localities were in some way unsuitable and that hence she had no occasion to return to them? Had she decided, in the last instance, that she would return and so must get her bearings? We wondered how far the different acts were instinctive, or were, as Huber has it, an evidence of a “little dose of judgment.” Bates, in speaking of Monedula signata, says that he often noticed it taking a few turns about the locality of its nest, and that he was convinced that it was doing so for the purpose of getting its bearings. Belt, having described how he fed a specimen of Polistes carnifex with a caterpillar, which the wasp cut into two parts, goes on to say: “Being at the time amidst a thick mass of fine–leaved climbing plant, it proceeded, before flying away, to take note of the place where it was leaving the other half. To do this, it hovered in front of it for a few seconds, then took small circles in front of it, then larger ones around the whole plant. I thought it had gone, but it returned again, and had another look at the opening in the dense foliage down which the other half of the caterpillar lay.”[2] He then remarks that when the wasp came back for the remaining half it flew straight to its nest without taking any further note of the locality. Both of these writers believe that many of the actions of insects that are ascribed to instinct are really evidence of the possession of a certain amount of intelligence.