BIRDS
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BIRDS' NESTS
made a plea for the establishing of such a day. Bird Day was observed in Oil City in 1895. In some states Arbor and Bird Day are observed as a single festival, in others there is a separation made.
Birds, a natural class of vertebrates. Other groups of equal value are Fishes, Amphibia, Reptilia and Mammals, each of which is called a class. Birds are distinguished from all other animals by possessing feathers. They moult or change the feathers once a year. They are warmblooded animals with a four-chambered heart; their lungs are connected with air-sacs, and the bones are often hollow and full of spaces which are connected with the air-sacs, to make them light for flight. Living birds have no teeth, but many fossil birds had teeth, and, strange as it may seem at first sight, the birds as a group are closely related to reptiles. As is well known, there were in geological times flying reptiles, and there is a bird (Arch&op-teryx) found in the rocks of Bavaria that forms a connecting link between birds and reptiles. The largest living birds are the ostriches, but the great fossil birds (Dinar-nis) of New Zealand were from six to ten feet in height. There are several other extinct birds of very large size. In the world to-day there are between 13,000 and 14,000 species.
The best way to observe our common birds is with the help of opera-glasses. We should go into the fields and woods armed with opera-glasses instead of a gun. Quietly reclining under the trees, we may, with field-glasses, bring the birds near enough to see their colors and observe many of their habits. Besides their beauty, birds are highly useful, destroying numberless insects and acting as agents in cross fertilization and seed planting. A good book to help is Chapman's Color Key to North American Birds.
The modern classification of birds includes the extinct forms, and is too technical to give here, but the following arrangement may be found convenient: Our common birds are either (a) water birds or (b) land birds. The water birds include divers, swimmers, waders, and the shore birds, represented by loons, gulls, ducks, geese, swans, auks and pelicans, herons, storks, ibises, cranes, rails and snipes, sandpipers, woodcocks, plovers and kill deer.
The land birds are more numerous. Here the largest order is that of the perching birds, embracing many families and representatives, including most of the song birds. Flycatchers, kingbird, phoebe, larks, crows, jays, blackbirds, oriole, bobolink, meadow lark, cowbird, sparrows and finches, song sparrow, field sparrow, goldfinch, purple finch, rose-breasted grosbeak, swallows, waxwings, warblers, threshers wren, catkird, mockingbird, red thrush, creepers,
nuthatch; the thrush family, blue bird, robin, hermit thrush, etc. Other families and representatives of the land birds are the scratchers: common fowl, turkey, pheasant, grouse, pigeons and doves; birds of prey: turkey buzzard, hawk, eagle, owl, cuckoos, kingfishers, wood-peckers, goatsuckers nighthawks, whip-poor-wills, swifts and humming biids. In addition to the above are the running birds; ostriches, emus, cassowaries.
See Chapman: Bird-Life (1899) and Bird Studies with Camera (1901); Davie: Nests and Eggs of Ar. A. Birds ($ih ed., 1898); Coues: Key to North A merican Birds; Blanchan: Birds Every Child Should Know; How to Attract the Bwds (1902); Bird Neighbors (1897); Birds that Hunt and are Hunted (1898); Dugmore: Bird Homes (1900); Merriam: Birds of Village and Field (1898).
Birds' Nests are primarily for rearing the young rather than for shelter. They show a great difference in architecture, from the most rude to the very complex, and birds may be divided into groups according to the way in which their nests are built. The mining birds either dig holes in the ground for their nests or use holes already dug by other animals. Thus the kingfisher digs a crooked gallery several feet into a bank and lays its eggs in a round hole at the end. Other birds of similar habits are the common bank swallow, the bee-eaters and the family of storm petrels. The wood-wren and the burrowing owl make their nests in ready-made burrows. Among ground-builders some build no nest at all, others only occasionally. The nighthawks lay their eggs on bare ground, as a large number of sea birds do on the sand. The brush turkeys of Australia, called mound builders, gather a large heap of decaying leaves and grass, and when the heap has become warm from rotting, dig a hole about two feet deep in the top, and lay their eggs, leaving them to hatch out by the heat. Vultures and common fowls belong to this group. The masons build their nests with walls or sometimes only coverings of mud. The cliff swallows build flask-shaped nests against the sides of rocks or cliffs. Several birds usually work at one nest, bringing mud, while one of their number directs the work from within. The baker bird of South America is the most skillful of this class. It builds its nests very high, in the shape of a baker's oven, with an entrance on the side twice as high as it is long, and the interior divided into two chambers by a partition. The common robin is allied to this group. The carpenters bore holes for their nests in trees. The woodpeckers, for example, dig with their beaks a short tunnel upward and then a larger hole downward, in the middle of the tree, where the eggs are laid. The platform builders include the eagle and pigeon. The level platforms of branches of trees and sticks built by eagles
