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 to rest, and soon they are asleep. But do not think, dear reader, that with the retirement of the Swallows every sign of life has ceased in the dark marsh for the night. Though the night has set in, we soon hear peculiar low tones coming from the thicket of reeds. We hear the melancholy song of the Sylvias, the voices of the Night Herons and of the Bitterns, and from time to time the gurgling cry of the sentinel among the gray Cranes mingles with them, generally followed up by the cries of the whole troop of Cranes. Another Crane takes the watch until his cry again puts these large birds on the alert against the sly attacks of hyenas and jackals.

The day is dawning. The song of the gray Sylvias and the Bittern’s loud boom are soon drowned in the noise of the hundreds of thousands of Swallows which have just awakened, and in the loud cries of the large birds, which try at first a walk on the moist bank of the swamp, before they leave for the plains. Our friends, the Swallows, rise after a good deal of squabbling about the dreams of the night past; they leave in small swarms—as I think, those coming from certain European districts keeping together for the whole time of their African sojourn—and make at once for the different portions of that endless plain, on which they are accustomed to hunt day after day. But they do not rise high up in the air to fly in any particular direction; taking the proper course at first, they commence at once to search for food, reaching their proper hunting-field—may it be near or very far off—by thus flying low along the high grass, and taking with their breakfast the glittering drops of the morning dew to quench their thirst.

Who could count the millions of insects the swarms of Swallows which rest at this one marsh destroy in a single day on that South African plain? Count now all the sleeping-places; count now all the swarms of this most useful bird; consider also the number of days of our winter, during which the Swallows remain in the far south; and if