II. FAMILY HIRUNDINIDÆ. THE SWALLOWS.
Plumage compact; size generally small; bill small, much depressed, very wide at base, and suddenly compressed to the tip, giving it a somewhat triangular shape; wings long; tail various, frequently forked; legs and feet short and weak.
These birds form a peculiar and easily-recognized family, species of which inhabit all parts of the world, and in civilized countries are generally regarded with favor. The Swallows are eminently social and gregarious, being almost constantly seen in companies even in the breeding season, and are amongst the comparatively few birds whose numbers are not diminished by the progress of the settlement and cultivation of countries. They subsist exclusively on insects captured on the wing, in the pursuit of which they exhibit extraordinary powers of flight.