until at last the latter gave up circling and doubling for a stretch of straight flight. In an instant, the flashing white wings of the falcon were above it; there was the same arrowy pounce with which the lesser falcon had struck down the teal; and, a moment later, the gyrfalcon had caught the falling body, and was volplaning down to earth with the dead plover in its claws.
For a time after this tragedy the sky seemed empty, as the scattered plover passed out of sight, to come together as a flock many miles beyond. Then a multitude of tiny black specks showed for an instant in the blue. They seemed almost like motes in the sunlight, save that, instead of dancing up and down, they shot forward with an almost inconceivable swiftness. It was as if a stream of bullets had suddenly become visible. Immeasurably faster than any bird of even twice its size, a flock of ruby-throated humming-birds, the smallest birds in the world, sped unfalteringly toward the sunland of the South. Their buzzing flight had a dipping, rolling motion, as they disappeared in the distance on their way to the Gulf of Mexico, whose seven hundred miles of treacherous water they would cover without a rest.
As the setting sun approached the rim of the world, the lower clouds changed from banks of snow into masses of fuming gold, splashed and blotched with an intolerable crimson. Again the sky was full of birds. Those last of the day-flyers were the swallow-folk. White-bellied tree swallows; barn swal-
