We may conclude our brief notice of marsh bird-life by a glimpse at the Black-headed Gull. This charming bird visits many a swampy piece of ground far from the sea during spring and summer to rear its young. In Lincolnshire there is an extensive gullery near Brigg--at Twigmoor--from which we have had many eggs during our long residence in South Yorkshire. There is another in South Yorkshire near Thorne; a third at Cockerham Moss in Lancashire. As we proceed northwards the colonies of this Gull increase in number, and in Scotland they are still more frequent. Many of these gulleries are situated on islands in pools in the marshes and on the heaths. Not a few of them are almost surrounded by trees of various kinds, and at the North Lincolnshire settlement nests are not unfrequently made in the branches. We have already described the colonies of the Black-headed Gull in previous works, so that but few details are needed here. In Lincolnshire the birds wander far and wide from their station near Brigg, and parties of them may be met with on the fields many miles from home. The Gulls are as regular in their habits as Rooks, with which we have often seen them fraternizing, flying out to feed on the wet meadows, and following the plough until evening, returning home in straggling streams just like their sable companions. As we get near Brigg the birds become more abundant in the fields; we remember, on one occasion, to have seen a ploughed field black and white with Rooks and Gulls, many of which when disturbed flew up from the furrows into the nearest trees; and very curious the white Gulls looked--birds that we associate with the water so closely--as they sat in the branches side by side with cawing Rooks. Early in the year, and before the birds leave the coast, the sooty-brown hood characteristic of the breeding season and of both sexes begins to be assumed. In Devonshire this takes place nearly a month earlier than in the north. In March they congregate at the old familiar stations which have been in use from time immemorial, and nest-building commences almost at once. The nests are ready for eggs by the first or second week in April. These are generally made upon the spongy ground of the marshy islands or on the marshes themselves, and in many cases are little more than hollows lined with a little dry grass. Other nests are bulkier, and these, we have often remarked, are nearest to the water, or even in the shallow pools. The three eggs are subject to much variation, but the ordinary type is brown or olive-green in ground colour, spotted and blotched with darker brown and gray. In many localities the eggs of the first laying are gathered by the tenant or proprietor of the gullery, as they are sold in vast numbers for food. Many, we know, are passed off as Plovers' eggs, but the fraud we should say would never be successful with anyone acquainted with the latter delicacy. The scene at the nests when the place is invaded by man is a very charming one, the Gulls rising in clouds into the air and wheeling about in bewildering confusion, uttering their noisy cries of remonstrance. Even more animated does the scene become when the young are hatched, for then the old birds show much greater solicitude. An inland gullery always seems to strike us as a trifle incongruous, for we are always apt to associate a Gull with the sea; yet here, miles away from the salt water, often surrounded by rural scenes, are Gulls in thousands as happy and contented as though they had never been near a coast in their lives. When the young are able to fly, however, the instinct of the sea apparently returns to them, and back they go to the salt water to wander far and wide, and lead a life of errantry until love brings them inland again in the following spring.