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 Europæus, Linn.) is migratory, arriving on the south-eastern 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
