It is possible, while the Wasp is storing her cell, to play her a trick which will show how purely mechanical her instincts are. A cell has just been completed, let us suppose, and the huntress arrives with her first Spider. She stores it away, and at once fastens her egg on the plumpest part of its body. She sets out on a second trip. I take advantage of her absence to remove with my tweezers from the bottom of the cell both the dead Spider and the egg. The disappearance of the egg must be discovered by the Wasp, one would think, if she possesses the least gleam of intelligence. The egg is small, it is true, but it lies on a comparatively large object, the Spider. What will the Wasp do when she finds the cell empty? Will she act sensibly, and repair her loss by laying a second egg? Not at all; she behaves most absurdly. What she does is to bring a second Spider, which she stores away with as much cheerful zeal as if nothing unfortunate had occurred. She brings a third and a fourth, and still others, each of whom I remove during her absence; so that every time she returns from the chase the storeroom is found empty. I have seen her persist obstinately for two days in seeking to fill the insatiable jar, while my patience in emptying it was equally unflagging. With the twentieth victim—possibly owing to the fatigue of so many journeys—the huntress considered that the pot was sufficiently supplied, and began most carefully to close the cell that contained absolutely nothing. The intelligence of insects is limited everywhere in this way. The accidental difficulty which one insect is powerless to overcome, any other, no matter what its species, will be equally unable to cope with. I could give a host of similar examples to show that insects are absolutely without reasoning power, notwithstanding the wonderful perfection of their work. A long series of experiments has forced me to conclude that they are neither free nor conscious in their industry. They build, weave, hunt, stab, and paralyse their prey, in the same way as they digest their food, or secrete the poison of their sting, without the least understanding of the means or the end. They are, I am convinced, completely ignorant of their own wonderful talents. Their instinct cannot be changed. Experience does not teach it; time does not awaken a glimmer in its unconsciousness. Pure instinct, if it stood alone, would leave the insect powerless in the face of circumstances. Yet circumstances are always changing, the unexpected is always happening. In this confusion some power is needed by the insect—as by every other creature—to teach it what to accept and what to refuse. It requires a guide of some kind, and this guide it certainly possesses. Intelligence is too fine a word for it: I will call it discernment. Is the insect conscious of what it does? Yes, and no. No, if its action is guided by instinct. Yes, if its action is the result of discernment.