Page:Natural History, Birds.djvu/37

24 and the size of its orifice, and partly by the beautifully serrated outer edge of the wing-primaries; which, allowing them to range without noise through the air, enables them to approach unheard their unsuspecting victim, which falls a prey to the silent flight and piercing eye of an inveterate enemy.

Some of the species are distinguished by having a series of feathers more or less lengthened, on each side of the top of the head, which can be erected at pleasure; when raised they have a very distant resemblance to horns, or to the erect ears of a cat, and hence these species are familiarly spoken of as horned or eared Owls.

Owls are dispersed over all parts of the globe; and several of the species enjoy a wide geographical range.

This genus, which is considered as exhibiting the peculiarities of the nocturnal birds of prey in the highest degree of development, is well illustrated by the most common British species of the Family, the White, or Screech Owl. Several species, very slightly differing from this, are found in various parts of the world, which may be characterized as having the head very large, without any tufts of erectile feathers, but with the face-disks very complete, and of great width; their extent is marked by dense semicircles of rigid narrow feathers, forming a sort of collar, with turned ends, lying close upon each other in the manner of scales. The orifice of the ear, which is within this collar, is also large, as is the