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Their colours are usually various shades of black, brown, grey, and white, mingled in the most beautiful manner, with minute waves, lines, and spots.
GENUS CAPRIMULGUS. (LINN.) The beak is here very minute and weak, the edges bent inwards, the mandibles not always meeting when closed. They are furnished with long bristles. The tarsi are short, but still distinct. All the toes are directed forwards; the inner and outer toes are equal; the middle claw is pectinate or comb-like. The foot is not formed for grasping; hence the birds sit lengthwise on a branch, not across it.
Our own beautiful Nightjar (Caprimulgus Europaus, LINN.) is migratory, arriving on the southeastern coasts of this island about the middle of May, and departing about the end of September. As soon as it arrives, the swarms of cockchafers become its nightly prey, and when their season is ended, the fern-chafer affords it a plentiful fare. Moths also, and other night-flying insects, are pursued by it, particularly around the summits of trees, and are readily engulfed in its cavernous mouth, surrounded by divergent bristles. It has been supposed, at least sometimes, to take its flying prey with its little foot, and deliver it to its mouth; and the securing of the insect in this manner has been thought one object of the serrated claw.
It frequently sits on a branch or a fence-rail, and, with the head held as low as the feet, utters, with swollen, quivering throat, its singular jarring note, for a long space at a time, without
seeming to draw breath. “As this song," says Mr. Jesse, “is a summer incident, the naturalist hears the first return of it with complacency; not from its melody, for it has none; but from
the pleasing association of summer ideas to which it gives rise.” “ Instead of being noxious and mischievous," continues this pleasing writer, “ they are the most harmless and useful of birds, destroying the great enemies of vegetation, the scarabæi and phalane, which, though individually feeble, yet are of mighty efficacy in their infinite numbers, inflicting wide devastations on the grass and corn, and stripping whole groves, woods, and extensive forests of their foliage at once, so as to make them look as naked as in winter.” “ Their wings and tails are very long, by means of which they excel in sudden evolutions; and they can mount instantaneously from a level flight, like a sky-rocket... When flushed in sunshine, they drop again at once, so as to be in danger of being caught by spaniels, and look round them with astonishment; hence a notion prevails that they are foolish birds."*
Like many other birds, the female Nightjar, if suddenly surprised by an intruder, when she has young, will feign helpless lameness, tumbling along in an odd manner,
the stranger from the centre of her anxious cares, by the hope of capturing her.
FAMILY II. HIRUNDINIDÆ.
In the smallness of the beak, and the great width of the gape, the Swallows resemble the Nightjars, as they do also in the weakness and minuteness of their feet. They are birds, however, of far more powerful wing, and though they too pursue insects, which are captured and devoured during flight, yet as their season of activity is wholly confined to daylight, their plumage has neither the lax softness, nor the mottled style of coloration common to nocturnal birds. On the contrary, the plumage of the Swallows is always close and smooth, and very often burnished with a metallic gloss; while its prevailing colours are black (more or less changing into blue or green) above, and white (often varied with dull red) beneath.
* Gleanings in Nat. Hist. 295.
The organs of flight are developed in a very high degree. Almost the whole life of these birds is passed in the air; from earliest “morn to dewy eve,” we see them careering along in their rushing flight, and, as has been truly observed, they “ dash along apparently as untired when evening closes, as when they began their aerial evolutions with the first dawn of day.” They even drink on the wing ;-sipping the pool or stream as they skim lightly over its surface. The feet, therefore, being little called into action, are small and weak; yet, as these birds frequently cling from rocks and walls, when they do rest, their toes are furnished with sharp and crooked claws, and the hind-toe can, either wholly, as in the Swifts, or partially, as in the common Chimney Swallow, be brought to point forward.
The Swallows, though widely dispersed over the globe, are eminently children of the sun: they extend, it is true, over the temperate zone, and even reach the Arctic Circle, but it is only in the summer season ; on the approach of cold weather, they retire to the torrid climes of equatorial regions. The Swift, which is the most impatient of cold of our visitors, does not appear in England until May, and hastens to depart before the end of August. In almost all the European languages the connection of these birds with a bright and fervid sun, is embodied in the well-known proverb,
“ One Swallow does not make a summer.”
GENUS HIRUNDO. (Linn.) The Swallows and Martins are distinguished from the Swifts by the following characters : the toes are directed, as in most Passerine birds, three forward and one backward; the feet are slender and comparatively weak, as are also the claws; the tail consists of twelve feathers, and is for the most part forked, often to a great extent; the wings have the first quill-feather the longest.
The Chimney Swallow (Hirundo rustica, Linn.) with its burnished upper plumage of steel-blue, its forehead and throat of chestnut-red, and its long forked tail, is well known; and its headlong flights and rapid evolutions as it plays over the stream or rushes through the streets of the town, are hailed as the attendants of summer. Who does not know the pleasant associations of the announcement,
The Swallows are come!” « The Swallow," says Sir Humphrey Davy, " is one of my favourite birds, and a rival of the Nightingale ; for he glads my sense of seeing as much as the other does my sense of hearing. He is the joyous prophet of the year, the harbinger of the best season; he lives a life of enjoyment among the loveliest forms of nature; winter is unknown to him, and he leaves the green meadows of England in autumn for the myrtle and orange groves of Italy, and for the plains of Africa."
In the “ Natural History of Selborne,” the economy of this, as well as of our other species of Hirundinida, is detailed in an interesting manner. The Chimney Swallow usually arrives in this