When I first heard this bird sing I felt convinced that no other feathered songster on the globe could compare with it; for besides the faculty of reproducing the songs of other species, which it possesses in common with the Virginian Mocking-bird, it has a song of its own, which I believed matchless; and in this belief I was confirmed when, shortly after hearing it, I visited England, and found of how much less account than this Patagonian bird, which no poet has ever praised, were the sweetest of the famed melodists of the Old World. Fam. II. CINCLIDÆ, or DIPPERS. The Dippers, constituting the genus _Cinclus_ and the family Cinclidæ, are sparingly distributed, principally in the Alpine Regions which contain clear and perennial streams, throughout the Palæarctic and Nearctic Regions. In the Neotropical Region they are represented by three species, one of which is found in the northern provinces of the Argentine Republic. 9. CINCLUS SCHULZI, Cab. (SCHULZ'S DIPPER.) [Plate II.] [Illustration: CINCLUS SCHULZI.] +Cinclus schulzi+, _Cab. J. f. O._ 1883, p. 102, t. ii. fig. 3. _Description._--Dark grey; throat pale rufous; a broad bar on the inner webs of the wing-feathers white: total length 5·5 inches, wing 3·0, tail 1·6. _Hab._ Northern Argentina. A recent discovery of Herr Fritsch Schulz, who obtained specimens of it on the Cerro Vayo of Tucuman, where this species, like others of the genus, frequents the mountain-streams. Fam. III. MUSCICAPIDÆ, or FLYCATCHERS. The peculiar genus _Polioptila_, which contains some twelve or thirteen species of small-sized American birds, ranging from the United States to the Argentine Republic, has been variously arranged by naturalists, but seems to be more nearly related to the African genus _Stenostira_ than to any other known form. I therefore now place it with the Muscicapidæ, or Flycatchers, of which it is the only genus found in the New World. 10. POLIOPTILA DUMICOLA (Vieill.). (BRUSH-LOVING FLY-SNAPPER.) +Polioptila dumicola+, _Scl. et Salv. Nomencl._ p. 4; _Durnford, Ibis_, 1876, p. 157, 1877, p. 167 (Buenos Ayres); _Salv. Ibis_, 1880, p. 352 (Tucuman); _White, P. Z. S._ 1882, p. 593 (Buenos Ayres); _Barrows, Bull. Nutt. Orn. Cl._ viii. p. 86 (Concepcion); _Sharpe, Cat. B._ x. p. 444. +Culicivora dumicola+, _Burm. La-Plata Reise_, ii. p. 473 (Paraná). +Culicivora boliviana+, _Scl. P. Z. S._ 1852, p. 34, pl. xlvii.