The _Hirundine_ Birds, or Swallows, form a very distinct group; they have slender bodies, and large, powerful wings, which enable them to fly with great velocity, skimming over the moist meadows, where their insect food most abounds, and wheeling and circling about trees and buildings in a swift and easy manner, which appears to be the very perfection of motion. They are all migratory birds, coming to us from Africa and the south of Europe to breed, and returning to those warm climates to pass the winter. The Common Swallow, called by naturalists _Hirundo rustica_, the first word signifying a Swallow, and the second, of, or belonging to the country, generally arrives in Britain in the latter half of the month of April, or the beginning of May, some time in which month the nest is commenced; it is of a broad cup-like shape, and is formed of moist earth, collected bit by bit from the side of a pond or stream, and moulded together with straw and grass: there is a lining of feathers, or some other soft materials. The situations chosen are sheltered spots beneath eaves or projecting roofs of any kind, shafts of mines, holes in the sides of pits and quarries, old wells and out-buildings, bell turrets, the under sides of spouts and bridge arches; most usually the spot selected is near human habitations. Who is not awakened in the bright summer mornings by the twittering of the young birds near his bed-room window? These birds have frequently been known to build in empty unused rooms, to which access could be gained through a broken pane of glass; they are said to nestle near chimneys for the sake of the warmth, being apparently not at all annoyed by the smoke which issues thence.