_Description._--Above olivaceous brown, tinged with rufous, brighter on the crown; lores yellowish white, superciliaries and sides of head whitish grey; wing-feathers dark olive-brown, the inner webs edged with ochraceous; tail black, all the rectrices, except the middle pair, slightly tipped and broadly spotted on the inner webs with white; beneath greyish white, the feathers from the lower throat to the belly transversely barred with black; bill and feet black: whole length 6·2 inches, wing 2·7, tail 2·6. _Female_: above the same as the male, except the tail, which is rufous brown; beneath whitish, tinged with ochraceous, and with scarcely perceptible greyish mottlings. _Hab._ Paraguay and Argentina. This species is very common in the eastern provinces of Argentina, and extends south to Buenos Ayres. It is a shy, solitary bird, found in woods and thickets along the shores of La Plata; and utters occasionally a singular low rasping note, its only language. The nest is a slight shallow structure placed in a low tree; the eggs are white, thinly spotted with reddish brown. Probably this species is to some extent migratory, as I have only observed it in the summer season. Fam. XIX. PTEROPTOCHIDÆ, or TAPACOLAS. The Pteroptochidæ form a small but very peculiar family of Tracheophonine Passeres, mostly restricted to Chili and the south-western extremity of the South-American Continent, but also represented in the Andes of Ecuador and Colombia and in the high plateau of Central Brazil. They are ground-birds, remarkable for their large and robust feet with long claws, their strangely formed bills, and the elevated position in which the tail is carried in the living bird. In the Argentine Republic four species of Pteroptochidæ are known to occur, only one of which, however, is a well-known bird. Two of the remaining three are recent discoveries, and the fourth a Chilian species, which extends over the Andes into the western borders of Argentina. 226. SCYTALOPUS SUPERCILIARIS, Cab. (WHITE-EYEBROWED SCYTALOPUS.) +Scytalopus superciliaris+, _Cab. Journ. f. Orn._ 1883, p. 105, t. ii. fig. 3 (Tucuman). _Description._--Nearest to _S. indigoticus_ of Brazil, but without the white colour on the breast and belly, only the throat being clear white; superciliaries striped white; front and sides of the head and neck, breast and belly grey; rest of the upper surface, together with the flanks and crissum, light brown, with fine blackish cross-markings; bill blackish, feet light-coloured. _Hab._ Sierra of Tucuman. This species is one of Schulz's recent discoveries in the Sierra of Tucuman, where he found it west of Sauciyaca, frequenting the deep ravines. 227. RHINOCRYPTA LANCEOLATA, Geoffr. et d'Orb. (GALLITO.)