rapidity amidst the flock, miss out some individuals, though right in the midst of those that are affected, in a manner which is hard to account for. Again, if we suppose two centres from which two opposite thought-waves or impulses spread, we can understand two groups of birds, which, together, have made one band, acting in different ways or going in different directions (as one may constantly see with rooks and starlings), whilst, by supposing that the wave, or energy, tends to exhaust itself after spreading to a certain distance around any point or centre where it may have originated or become focussed, we account for such facts as many thousands of starlings, say, rising from, perhaps, a million without the others being affected. But, no doubt, even in an Athenian assembly there were some men capable of withstanding the force of the φημη, and if we give to birds, even when thus assembled together, a power of individual as well as collective action, varying in each unit so that the one power is now more and now less under the control of the other—but with, on the whole, a preponderance in favour of the latter—we then, as it appears to me, come near to explaining what I must regard as the often very puzzling problem of the movements of such assembled bodies. This, of course, is the theory of thought-transference, and if this power does really exist in the case of any one species we might expect it to exist also in the case of others. With the evidence of its existence amongst ourselves I am not unacquainted, but I need say nothing of this or of my humble opinion concerning it, here. I have suggested it as a possible explanation of some of the actions of birds,
