by having its poll scratched; though, with regard to this, we must not forget the look of supreme satisfaction which a monkey often has whilst a friend is doing his best to make him clean and respectable. With the foot-cleaning there is no such attitude and expression. The bird helped is at the same time an active agent, and both of them are careful, earnest, and investigatory. It struck me, however, that the chick was cosseted in a somewhat more business-like manner, as though, if not actually to clean it, at least to make it spruce and tidy. It seems probable, indeed, that the conferring a practical benefit of the kind indicated may be one origin of the caress throughout nature; but others may be imagined.
The usual cause of guillemots fighting would seem to be one of them moving to a sufficient degree to attract the attention of the one nearest to it, who then—as though the circumstances permitted of no other course—delivers a vigorous thrust with its long, spear-like bill. This is the usual way of fighting, so that a combat has something the appearance of a fencing-match. The two birds stand upright with their bodies turned more sideways towards each other, than actually fronting, so that their heads, which alone do so, are twisted a little round. They stand at such a distance apart, that when the neck is held straight up, with the head flying out at a right angle, the tips of their two long lances just touch, so that the birds form a natural archway. In this position they make quick, repeated thrusts at each other, usually directed at the face or neck, by a motion of which, rather than by parrying with the beak, each endeavours to avoid the lunge of its adversary. But besides
