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 love-making, great numbers are continually flying hither and thither in search of materials with which to build, so that the whole hill is surrounded with them, and when seen at a distance they present very much the appearance of a swarm of bees. Previous to our visiting Lapland we had read descriptions of these breeding-places, but from them had formed a very imperfect conception of the reality. Never shall we forget the day on which we made an excursion to Svärrholt, not very far from the North Cape. The vast perpendicular front of the rock to which the Gulls resorted, looked as we approached it like a gigantic slate covered all over with millions of little white dots. On our firing a gun, all these millions of shining points seemed to detach themselves from the dark background, afterwards to become alive, next to become Sea Gulls, and then to pour themselves in a continuous stream into the sea. Looking upwards it seemed exactly as if a great snow-storm had begun to shower gigantic flakes from the skies—for minutes together it snowed birds, the whole sea, as far as we could discern, was thickly covered with them, and yet the surface of the rock seemed as densely peopled with birds as at first. We had before thought the narratives we had read were exaggerations, we now found them to be far below the truth. In every nest these birds lay three or four eggs of a dirty rusty yellow, sparsely besprinkled with dots and streaks of a darker tint. It is only reasonable to suppose that each pair devote themselves exclusively to the incubation of their own eggs and the rearing of their own young. But how a pair, among all those hundreds of thousands of nests can ever find their own abode, or even each other, when they have once left their place even for a minute is beyond our comprehension. The young birds remain in the nest till the middle of August, at which time they are sufficiently fledged to enable them to fly out to sea and add their voice to the deafening screeching of their fellows.

The BLACK-HEADED GULLS (Chroicocephalus) constitute a group whose most conspicuous character is that, when in their nuptial dress, their head is covered, as it were, with a black cap. We can hardly, from this circumstance, regard them as a distinct sub-family; nevertheless, they present certain peculiarities not common to the race. All these birds inhabit temperate climates, and seldom or never appear in the northern regions visited by so many other species. The food of the Black-headed Gulls consists principally of insects and small fishes; however, they by no means despise small quadrupeds or carrion. Insects they generally catch in the water and pick from the surface of the ground, but occasionally they take them while on the wing. The young are fed almost exclusively on insects.

THE LAUGHING GULL.

The (Chroicocephalus ridibundus). The adult in summer has the head, occiput, and upper part of the neck of a dark brown, the colour being most intense when first assumed, and becoming lighter by time and wear; the sides and back of the neck are pure white; the back, wing-covers, secondaries, and tertials, uniform French grey; the first three quill primaries white on the shafts and webs, but margined with black; the fourth white on the outer web, grey on the inner web, and edged with black; the fifth and sixth grey on both webs, the edge of the inner or broader web and the point black; tail-covers and tail-feathers white; front of the neck, breast, and all the under surface of the body and tail pure white; legs and feet, like the beak, are vermilion-red; irides hazel; eyelids orange.

The adult bird in winter has the head only slightly marked with a dusky patch at the ear-covers. The young are brownish on the upper parts of the body. This species is sixteen inches long, and thirty-six inches broad; the wing measures twelve and tail five inches.

With regard to the change in colour of the head according to the season of the year, Mr. Yarrell observes: "A Gull in the collection at the Gardens of the Zoological Society began to change colour