SUB-FAMILY STRIGINÆ
Bill somewhat elongated, bending at the tip only; head-tufts wanting nostrils oval, oblique; facial disc large and complete; ears large, covered by an operculum; wings long, the second primary longest; tarsi long, feathered to the toes, which are strangely furnished with hair-like feathers; claws long, the middle one serrated beneath.
58. Strix (White Owl). Characters given above.
SUB-FAMILY SYRNIINÆ
Bill bending from the base; tufts more or less conspicuous or wanting; facial disc complete; ears large, covered by an operculum; legs feathered to the claws.
59. Asio (Eared Owls). Nostrils oval, oblique; tufts more or less elongated; wings long, second primary the longest.
60. Syrnium (Tawny Owl). Nostrils round; egrets wanting; wings short and rounded; fourth primary longest.