Family IV. CAPRIMULGINAE. GOATSUCKERS.

Mouth opening to beneath the centre of the eyes; bill much depressed, generally feeble, the horny part being small; upper mandible with the tip somewhat decurved. Nostrils elliptical, prominent, marginate. Eyes extremely large. Aperture of ear elliptical, very large. Head of extreme breadth, depressed; body very slender. Feet very small; tarsus partially feathered, scaly; anterior toes webbed at the base; hind toe small, and versatile, all scutellate above; claw of third toe generally elongated, with the inner margin thin and pectinate. Plumage very soft and blended. Wins very long, the second and third quills longest. Tail long, of ten feathers. OEsophagus rather wide, without crop; stomach very large, roundish, its muscular coat very thin, and composed of a single series of strong fasciculi; epithelium very hard, with longitudinal rugae; intestine short and wide; coeca large, oblong, narrow at the base; cloaca globular. Trachea of nearly uniform width, without inferior laryngeal muscles. Nest on the ground, or in hollow trees. Eggs generally two. Young covered with down. Very nearly allied in some respects to the Owls.