Page:Popular Science Monthly Volume 61.djvu/356

350 fireside. Here, however, the attentions are lavished, not only on the newcomer, but on those who were the first to meet him, and plainly the meaning of the whole performance is simply the distribution of nectar by one of the wasps which has just returned from a foraging expedition. Earlier in the season, this nectar is regurgitated into the mouths of the feeding larvæ, but in their absence it is stored in the cells or serves directly as food for the adults.

Finally, I think the habits Polistes acquires may bear a decided relation to its rhythm of activity and repose. If we watch any wasp community, we see that periods of general sluggishness alternate with furies of activity and, in the case of the individual, any marked exertion is always promptly followed by great quiescence. Of course, what actually happens to the nervous system when impressions are fixed and habits formed is largely a matter of conjecture. But in the establishment of any reaction, it is generally thought that the repair of the nervous element is quite as important as the change which it undergoes while the reaction is taking place. And it would seem that the delicate nervous organization here implied would lend itself readily to the 'stamping in' of reactions or trains of reactions. That is, a particular performance, once called forth, would the more readily occur had a period of repose prevented the reception of any intervening impression and brought about the restitution of the nervous mechanism affecting the reaction in question.

The period of repose on the nest is usually terminated by one of the wasps starting up and commencing an examination of the cells of the nest. Others immediately follow suit, until the whole colony is in a tumult. But it is not the example of the first wasp that is responsible for this, only the external stimulus furnished the sleeping colony by the movements of the first wasp on the nest. Simple tests prove this. Godart relates how the colonies of Bombus have a trumpeter-bee, whose duty it is to rouse the colony to work in the morning. If this bee is removed, another takes its place the following day. An observer of a wasp colony might easily believe that similar duties had been delegated to particular wasps. But here, and probably in the case of Bombus, it is the fact that any external stimulus, such as a loud noise or jarring the nest, produces the same effect. The wasp examines the cells not because it is aroused to a sense of duty by seeing what the others are doing, but because this is the habitual response whenever it is gently stimulated while on the nest, by any means whatever.

In summarizing these observations, it may be said that, although they are perhaps hardly extensive enough to warrant definite conclusions concerning wasp intellection, they nevertheless indicate several things: