which the satellite bird, assuming, at last, his proper height, delivers into it, from his own, something which he appears to bring up, and this, as it seems to me, is swallowed by the bird receiving it. The morsel is small, but the actions of giving and taking, and, afterwards, the movements of the beak and throat of the bird that has parted with it, are unmistakable. This would appear, therefore, to be a little friendly act, or, perhaps, an act of courtship—a love-token between the male and female bird—and I take the bird who delivers the morsel, and who is cream-marked, to be the male, and the other, who is uniformly dark, the female."
Skuas, as is well known, attack one if one comes at all near to their nest, and gulls—at any rate the two black-backed kinds—will sometimes, though much more rarely, come very near to doing so too. For instance, the greater black-backed gull swoops at one backwards and forwards, in the same way (though more clumsily) as do the skuas, except that he neither touches you nor comes so near. Every time he passes he gives a loud, harsh, tuneless cry, and drops down his legs as though intending to strike with them. When he does this, he may be some five or six feet above one's head—a little more, perhaps, or a little less—and presents an odd, uncouth appearance. The skuas swoop in silence, though the great one continually says "ik, ik" (or words to that effect), whilst circling between the swoops. "On another occasion two of the lesser black-backed gulls acted in this way, though one of them continued to do so for a much longer time. These two seemed to be angry with each other, making little motions and opening their bills in the air as though each thought it was the
