the brilliant yellow gule which matches in colour the naked outer skin at the base of the mandibles becomes plainly visible. This habit of opening the bill as it were at each other I have remarked in several seabirds, and also that in all or most of these cases the interior part thus disclosed is brightly or, at least, pleasingly coloured.
Bathing.—But whether the following be bathing or a kind of aquatic exercise either of or not of the nature of sexual display, I will leave to the reader to decide. Birds which live habitually in the water do yet bathe, I believe, in the proper sense of the word.
"The cormorant, when bathing, raises himself a little out of the water whilst still maintaining a horizontal position, and in this attitude, supported as it would seem on the feet, he commences violently to beat the sea with his wings, moving also the tail and, I think, treading down with the feet upon the water. The sea is soon beaten all into foam, and when he has accomplished this, desisting, he begins to sport about in the whiteness of it in an odd excited manner, making little turns and darts and often being just submerged, but no more. He does this for a few minutes, stops, and commences again after a short interval, and thus continues alternately sporting and resting for a quarter of an hour or, perhaps, even as long as half-an-hour. I think this must be bathing or washing, for other birds act in the same way, though less markedly, so that it does not occur to one to wonder what they are about. The little black guillemot, for instance, beats the water briskly and rapidly with his wings, but whereas the cormorant
