another, as though it were a game or romp. Sometimes, indeed, there will be a little bit of a scuffle; but if there be fighting, still more, as it appears to me, is there the play or pretence of fighting, which is tending to pass into a social sport or dance.
The antics of birds are often so very curious, and the whole subject of their origin and meaning is so full of interest, that nothing which might by any possibility throw light upon this ought to be neglected, or can be too closely observed. I believe that the feelings of animals, still more than is known to be the case with savages, pass easily from one channel into another, and that, therefore, nervous excitement brought forth by one kind of emotion is apt, in its turn, to produce another kind, so that if any special transition of this sort were at all frequent, it might, through memory and association of ideas, become habitual. If, however, a mêlée or scrimmage—to meet the case of these guillemots—became, almost as soon as started, a mere hurrying and scurrying about, it would be difficult to detect the one as the cause of the other, and this is just the difficulty one might expect, for in such a sequence the tendency would, no doubt, be for the first or causal part of the activity to become more and more abbreviated (what should delay the passage?) till, at length, a mere start on the part of any one bird might set the others off dancing. Finally, what had become a mere pretence or starting-point might vanish entirely, or only survive as an indistinguishable part of the other, in which case there
