NIGHTJAR. A general term. derived from their nocturnal habits and jarring utterances on the wing. for the large family Caprimulgid:c (i.e. Whieh is nearly tan in extent. Nightjars are bird- varynig in size from eight to fifteen inches in length; all have light soft idumage, in finely mottled shades of gray. broun, and white: and they bear many resemblances to owls in structure as well as in their nocturnal and crepuscular habits. In some particulars they resemble the swills, and, like them, capture all their flood upon the wing; and, as moths form a conspicuous part of this, the tribe has been called 'moth-hunters: In pur suit of this prey Iloy are often seen in the (1114: about pastures with the vows or (in Southern Europe) with the goats: and their habit of dodg ing about the cattle after insects, together with their eapacious months. led to strange supersti• lions which are entirely without foundation. The wings ;ire long and powerful. and in the males of species are furnished with long orna mental feathers (see 5TA,Nn.s,110-WI,Nn) ; While in others some are lengthened. The legs and feet are small and weak, and tine middle toe is usually remarkably long, and serrated on its inner edge, so as to form a kind of comb attached to the toe. Although the bill is very short and weak, the gape is wide. as if the head itself were divided, and the mouth is surrounded by bristles, assisting the bird in securing its agile prey. All avoid activity in daylight. when they rest quiet on the ground, a log. stone, or large horizontal tree-branch. in
some shack• place, and almost always lengthwise I if the perch—a habit due not only to the feeble grasping power of the feet, but to the greater invisibility thus obtained. In ninny instances the birds have a further protective habit of stiffening themselves in certain positions where they resemble a knot, or a broken and projecting stick. and so escape notice. (See MoaEroaK.) They make no nests, or only very poor• ones, which are placed on the ground. The oblong eggs are usually two, and are whitish or incon spicuously marked. (See Colored Plate of Eons OF SONG-BIRDS.) The voice is a screaming. jarring, or booming note, produeed in flight; while many species have an oft-repeated cry. usually translatable into syllables, as • iv hip- poor Will' or 'chucko-Will's-widow.' About 100 species are known, included in about fourteen genera. of these, fora• or five genera with six species occur in the United States. The best known are the whippoorwill, chuck-Will's-widow. poorwill, and nighthawk (qq.v.). The best-known species of the Old World is the common nightjar, 'churn owl,' or 'fern-owl' (('aprimulgus Europalls), familiar throughout Central Europe, the ranean region, and Western Asia. The potoos (q.v.) of .Jamaica and South America represent a distinct subfamily (Nyetibiina.), and an aberrant form is the guacharo Consult standard authorities• especially New ton, Dictionary of Birds (London and New York, 1893-96). See Plate of NIGHTJARS. ETC.