[11.] DONACOBIUS ATRICAPILLUS (Linn.).
(BLACK-HEADED REED-WREN.)
Donacobius atricapillus, Scl. Cat. A. B. p. 16; Scl. et Salv. Nomencl. p. 5; Sharpe, Cat. B. vi. p. 364; Burm. La-Plata Reise, ii. p. 475. Donacobius brasiliensis, d’Orb. Voy., Ois. p. 213 (Corrientes).
Description.—Above dark chocolate-brown; cap black; wings black, with a large white patch on the inner primaries; tail black; lateral rectrices broadly ended with white; beneath ochreous buff; sides of breast and flanks with cross lines of dusky brown: total length 7·5 inches, wing 2·9, tail 3·7. Female similar.
Hab. Guiana, Amazonia, Brazil, Paraguay, and Northern Argentina.
The genus Donacobius contains two species somewhat intermediate between the Mock-birds and the large Wrens of the genus Campylorhynchus. The well-known Brazilian D. atricapillus extends through Paraguay, where Azara found it abundant, into Corrientes and the adjoining provinces of La Plata. It is met with among the reeds on lakes and streams.
[12.] TROGLODYTES FURVUS (Gm.).
(BROWN HOUSE-WREN.)
Troglodytes furvus, Scl. et Salv. P. Z. S. 1869, p. 158 (Conchitas); iid. Nomencl. p. 7; Durnford, Ibis, 1876, p. 157, 1877, p. 32 (Chupat), p. 167 (Buenos Ayres), 1878, p. 392 (Central Patagonia); White, P. Z. S. 1882, p. 593 (Buenos Ayres); Döring, Exp. al Rio Negro, Zool. p. 36 (Azul, R. Colorado, R. Negro). Troglodytes platensis, Burm. La-Plata Reise, ii. p. 476; Barrows, Bull. Nutt. Orn. Cl. viii. p. 86 (Concepcion). Troglodytes musculus, Sharpe, Cat. B. vi. p. 255.
Description.—Above brown; the tail-feathers and outer webs of wing-feathers pencilled with dark wavy lines; beneath very pale brown; bill and feet horn-colour; eye brown: total length 4·8 inches, wing 2·0, tail 1·7. Female similar.