302 INSECTIVOROUS BIRDS. 



black. Legs and feet bluish-grey, the hind claw rather the largest. 

 — The female merely differs by having the black and white adjoin- 

 ing the eye less pure and deep. 



VIREOS (or Warbling Flycatchers.) 



In these the bill is rather short, a little compressed, and furnished 

 with bristles at its base ; the upper mandible curved at the extremity 

 and strongly notched ; the lower is shorter, and recurved at tip. 

 Nostrils, at the base of the bill, rounded. Tongue cartilaginous and 

 cleft at the point. Tarsus longer than the middle toe. Winga 

 rather acute; the 2d or 3d primary longest. — Female resembling 

 the male. The species more or less tinged with olive-green. 



These birds, in the early part of summer, live exclusive- 

 ly on insects ; towards autumn they feed on small bitterish 

 or astringent berries, the hard, indigestible parts of which 

 are regurgitated by the bill, as with the Flycatchers. 

 They live almost wholly in trees, rarely ever alighting on 

 the ground. The voice is highly musical, and their song 

 long continued. At the approach of winter they migrate 

 to tropical climates. — They are peculiar to America. 

 Besides their other affinities, they are related to the true 

 Orioles, in which the young and females are also olive- 

 green : both build pendulous nests ; have similar colored 

 eggs ; their song is not very different ; and the young 

 of both mew somewhat like cats. 



YELLOW-THROATED VIREO. 



(Vireo flavifrons, Vieill. Bonap. Muscicapa sylricola, Wilson, i. 



p. 117. pi. 7. fig. 3. Phil. Museum, No. 6661 ?) 



Sp. Charact. — Yellow-olive; throat, breast, frontlet, and line 

 round the eye, yellow ; belly white ; wings with 2 white bands, 

 and, as well as the tail, blackish. 



