Chapter III: Family Strigidæ. the Owls

General form short and heavy, with the head apparently disproportionately large, and frequently furnished with ear-like tufts of feathers. Cavity of the ear, large; eyes, usually large, directed forwards, and in the greater number of species formed for seeing by twilight or in the night; bill, nearly concealed by projecting bristle-like feathers; wings, usually, rather long and formed for rather slow and noiseless flight, outer edges of primary quills fringed; tail, various, usually short; legs, generally, rather short, and in all the species, except those of the Asiatic genus _Ketupa_, Lesson, more or less feathered to the toes, generally densely; face surrounded by a more or less perfect disc or circle of short rigid feathers, which circle, with the large eyes directed forwards, gives to these birds an entirely peculiar and cat-like expression, indicative of their analogy to the _Feline_ quadrupeds.

Female larger than the male. General organization adapted to the destruction of living animals in the night, or in the morning and evening twilight—midnight appears to be the noon of these birds, at which they are not disposed to activity.

Species of owls inhabit all parts of the world, most abundantly in America and Asia. There are about one hundred and forty described species, of which number, specimens of about one hundred and twenty are in the collection of the Academy of Natural Sciences of Philadelphia. The species inhabiting the continent and islands of America are about forty.

A.

I. SUB-FAMILY STRIGINÆ. THE TRUE OR TYPICAL OWLS.

Head, large; facial disc, perfect; bill, rather long; eyes, of moderate size; wings, long; tail, moderate; legs, rather long, clothed with short feathers; toes, long—size, medium, never very large; colors of plumage in the greater number of species, yellowish-fawn color and white.