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 they were honestly entitled, for they seem to leave the rest, mostly, for the chicks, of which there are, commonly, two. At any rate, a number of the herrings will have only a small portion eaten off them. There is a great profusion, amounting to waste, and there does not seem any reason why the skuas should vary their diet during the breeding season, as they are asserted to do, since they have the sea always at hand, and the gulls, that are to them as their milch cows, breed in their close proximity.

In the skuas we see the habit of obtaining food by forcing another bird to disgorge what it has swallowed, perfected and become permanent, so that the birds practising it have risen—shall we say?—into rapacious parasites; but amongst the gulls themselves, who suffer by the practice, we may see, if I am not mistaken, the habit in its incipiency, and may get a hint as to how it might have arisen. When fishing-smacks are in harbour they are thronged round, sometimes, by hundreds of gulls, all the more common kinds—viz. the lesser and greater black-backed, herring-gulls, and kittiwakes—being mixed and crowded together. When some offal is thrown out, the birds that secure any are at once mobbed, and often it is torn away from them almost before they have swallowed a mouthful. To avoid this, they often rise with it in the beak and get it down as fast as they can on the wing, dodging and jerking their head from side to side amongst the pursuing crowd. But I have observed that the pursuit does not always cease after the morsel has been swallowed, and sometimes—whether rarely or frequently I am unable to say—the oppressed gull disgorges it again, in order