Hirundo Linn., Syst. Nat., 10th ed. i, p. 191 (1758). Type, Hirundo rustica Linn.
The genus Hirundo comprises the true Swallows, which are for the most part familiar and well-known birds.
The species of this genus have the greater part of the back deep, glossy steel-blue. In the majority the tail is deeply forked, in a few it is nearly square.
Key to Species,
A. Bump blue or brown; lower plumage not streaked. a. White spots on tail.
a1. A broad complete or semi-complete pectoral band
b1. No trace of a pectoral band.
a2 Chin, throat and fore-neck white.
b2 . Chin, throat and fore-neck chestnut.
b. No white spots on tail.
B. Bump chestnut; lower plumage streaked.