Goat-sucker, or Fern-pool, in ornithology, a genus of birds belonging to the order of passerine. The beak is incurvated, small, tapering, and depressed at the base; the mouth opens very wide. There are two species. 1. The Europeus, with the tubes of the nostrils hardly visible. It feeds on moths, gnats, dorr or chaffers; from which Chariton calls it a dorr-buwek; its food being entirely of that species of beetle during the month of July, the period of that insect's flight in this country. This bird migrates. It makes but a short stay with us: appears the latter end of May; and disappears, in the northern parts of our island, the latter end of August; but, in the southern, stays above a month later. It inhabits all parts of Britain from Cornwall to the county of Roos. Mr Scopoli seems to credit the report of their sucking the teats of goats, an error delivered down from the days of Aristotle. Its notes are most singular. The loudest so much resembles that of a large spinning wheel, that the Welsh call this bird aderyn y dreell, or the wheel-bird. It begins its song most punctually on the close of day, sitting usually on a bare bough, with the head lower than the tail, the lower jaw quivering with the efforts. The noise is so very violent, as to give a sensible vibration to any little building it chances to alight on and emit this species of note. The other is a sharp squeak, which it repeats often; this seems a note of love, as it is observed to reiterate it when in pursuit of the female among the trees. It lays its eggs on the bare ground; usually two; they are of a long form, of a whitish hue, prettily marbled with reddish brown. The length of this bird is 10½ inches; extent 22. Plumage, a beautiful mixture of white, black, ash-colour, and ferruginous, disposed in lines, bars, and spots. The male is distinguished from the female by a great oval white spot near the end of the three first quill-feathers, and another on the outmost feathers of the tail.—2. The Americanus, has the tubes of the nostrils very conspicuous. It is a night-bird, and is found in America.