Bill very short, strong, cerate; upper mandible with the tip elongated and decurved; lower mandible with the end rounded and thin-edged. Head extremely large, owing to the wide separation of the tables of the cranium, roundish, more or less vertically flattened behind, feathered. Eyes excessively large, with prominent superciliary ridges, and encircled by series of decomposed feathers. External aperture of ear always very large, frequently excessive, simple or operculate. Tarsus short, very short, or of moderate length, always feathered, as are the toes, of which the outer is versatile, the first shorter than the second, the anterior free; claws very long, slender, curved, extremely acute. Plumage very full and soft. Wings long, broad, rounded, the second, third, and fourth quills longest, the filaments of the outer more or less enlarged and recurved at the end. Tail broad, rather short or of moderate length, of twelve feathers. Œsophagus very wide, without crop or dilatation; stomach very large, round, somewhat membranous, its muscular fasciculi being placed in a single series; intestine short and wide; cœca large, oblong, obtuse, narrowed at the base. Young at first covered with light-coloured down, when fledged, with the face darker than that of adults. Eggs white, somewhat globular or broadly ovate, from four to six. Nests rudely constructed, in hollow trees, on branches, in buildings, or on the ground. GENUS I. SURNIA, Dumeril. DAY-OWL. Bill very short, strong, its upper outline decurved from the base; lower mandible abruptly rounded, with a sinus on each side. Nostrils elliptical, rather large. Aperture of ear elliptical, simple, not more than half the height of the head. Feet strong; tarsi very short or of moderate length. Plumage rather dense; facial disks incomplete above. Wings very large, the third quill longest, the first with the filaments thickened and a little free, but scarcely recurved at the end. Tail varying in length. 27. 1. Surnia funerea, Gmel. Hawk Day-Owl.--Hawk Owl. Plate CCCLXXVIII. Male and Female. Tail long, much rounded, the lateral feathers two inches shorter than the middle. Upper part of head brownish-black, closely spotted with white, hind neck black, with two broad longitudinal bands of white spots; rest of upper parts dark brown, spotted with white; tail with eight transverse bars of white, the feathers tipped with the same; facial disks greyish-white, margined with black; lower parts transversely barred with brown and dull white. _Male_, 15-3/4, 31-1/2. _Female_, 17-1/2. From New Jersey on the east, and from Columbia River on the west, northward; but not in the central plains. Migratory. Hawk Owl, Strix hudsonica, Wils. v. vi. p. 64. Strix funerea, Bonap. Syn. p. 35. Hawk Owl, Strix funerea, Nutt. Man. v. i. p. 115. 28. 2. Surnia nyctea, Linn. Snowy Day-Owl.--Snowy Owl. Plate CXXI. Male and Female.