[98.] AGELÆUS FLAVUS (Gm.).
(YELLOW-HEADED MARSH-BIRD.)
Xanthosomus flavus, Scl. et Salv. P. Z. S. 1869, p. 632 (Buenos Ayres); iid. Nomencl. p. 37; Durnford, Ibis, 1878, p. 59 (Buenos Ayres); Döring, Exp. al Rio Negro, Zool. p. 41 (Carhué); Barrows, Bull. Nutt. Orn. Cl. viii. p. 134 (Entrerios). Agelæus flavus, Scl. Cat. B. xi. p. 346.
Description.—Black; head and rump, bend of the wing, and body beneath bright yellow; bill and feet black: whole length 6·7 inches, wing 4·2, tail 3·2. Female: above brown, slightly striated; eyebrows, rump, and body beneath yellowish; bill and feet brown.
Hab. Paraguay, Uruguay, and Argentina.
Azara called this bird Cabeza amarilla, or Yellow-head. It is found throughout the eastern provinces of the Argentine country, ranging south to about the thirty-sixth degree of latitude, and is also common in the Banda Oriental.
The dull-plumaged birds are always very much more numerous than the bright-coloured males, though Azara strangely asserts that the sexes are alike. In Buenos Ayres, where it is called “Naranjo” by the country people in allusion to its orange tints, it is very well known on account of its yellow plumage, which looks so wonderfully brilliant in the sunshine, and its partiality for cultivated districts, where it follows the plough to pick up worms, and frequents the orchard to sing, associating with the common Cow-bird and Yellow-breast. It remains all the year, and is very sociable, going in flocks of from twenty to fifty individuals, which when they settle on the trees all sing in concert, pouring out their few peculiar notes with great power and emphasis.
Even in the breeding-season these companies do not always break up, and frequently several pairs have nests near together. The nest is usually built in a cardoon thistle, two or three feet above the ground, and is made of dry grass. The eggs are four, pointed, white or with a bluish tinge, and speckled irregularly with deep brown, the spots being closer and sometimes confluent at the broad end.
Concerning the plumage of this species Mr. Barrows writes:—“Late in March, 1881, we found this species in large flocks on the Pigué, and it was a beautiful sight to see a hundred or more fluttering about among the snowy plumes of the pampas grass, and displaying their rich black and yellow dress. Unlike most other birds obtained at that time, their plumage seemed nearly as bright and fresh as in summer.”