VIREO, or Greenlet, a common name of a family of American insectivorous birds, coming near the shrikes in the form of the bill and in some of their habits. The general plumage is more or less tinted with green and olive. In the typical genus vireo (Vieill., since subdivided by Prince Bonaparte into vireosylvia and vireolanius or lanivireo), the bill is short and strong, nearly straight, notched and hooked at the tip, with a few weak bristles at the gape; wings long and pointed; toes moderate, the lateral ones partly united to the middle at the base, and capable of holding their insect prey as in the shrikes; tail moderate and even. There are about 20 species, all small, migrating from South America and the West Indies to the United States, arriving here about May, breeding in summer, and returning in autumn; many are sweet singers. They are very active, feeding on insects and their larvæ, which they take on trees or on the wing, and sometimes on berries; the nest is made in trees and bushes, of dried leaves, grasses, roots, moss, and lichens, and is generally pendulous; they exhibit great jealousy of any intruder on their retreats, and scold and chatter in a most extraordinary manner; most have two broods in a season, with four or five eggs, white with brown or black spots; their nests are often selected by the cowpen bird for the reception of its parasite eggs. The red-eyed vireo (V. olivaceus, Vieill.), the type of vireosylvia, is 6½ in. long and 10½ in. in alar extent; the upper parts and tail are bright olivaceous green; crown ashy, bordered on each side by a dusky line within a white superciliary one; nearly pure white below, under tail coverts with a faint sulphur tinge; iris red. It is found from the eastern United States to the Missouri, S. to Texas and Central America, and N. to Greenland. The nest is very neatly made, suspended from twigs 4 or 5 ft. from the ground; besides the usual materials, it includes bits of hornets' nests, flax, and paper, glued together, according to Wilson, by the silk of caterpillars and the bird's saliva; it is so durable that other birds, like the yellow bird, have been known to build in the preceding year's nest; even mice have sometimes occupied it after the bird has left it. A more southern species, much resembling this, the V. barbatulus (Baird), is popularly called “Whip-Tom-Kelly,” from a fancied resemblance of its notes to those words; Mr. Gosse thinks they resemble more “John-to-whit,” and Dr. Bryant adds to the former the syllables “pheuu, wheuu,” much prolonged.—The white-eyed vireo (V. Noveboracensis, Bonap.) is about 5 in. long and 8 in. in alar extent; it is olive-green above and white below; ring around eyes, extending to bill, greenish yellow; two bands on wings and edge of inner secondaries white; sides of head and breast strongly tinged with yellow; iris white. It is found in about the same extent as the preceding, but not so far north; it so often introduces fragments of newspapers into its nest, that it goes in some places by the name of the politician.—The solitary vireo (V. [lanivireo] solitarius, Baird) is 5½ in. long and 9¼ in. in extent of wings; head and neck above dark bluish ash, rest of upper parts olive-green; white ring around eyes, extending interruptedly to bill; lower parts, two bands on wings, and edge of secondaries white; under wings greenish yellow. It is found in the United States from the Atlantic to the northern Pacific.
Red-eyed Vireo (Vireo olivaceus).