Adult: Greyish olive, very slightly mixed with rufous, a line from the nostrils reaching behind the eyes and cheeks, yellow; the space between the bill and eye, and the entire throat, deep black; the secondaries blackish, broadly margined with grey and olive; the primaries blackish, slightly margined with yellow; the tail greyish black, with the outer feathers white; beneath the body yellowish white, darker on the flanks. Female: Upper surface brownish white, with each feather blackish brown in the middle, the head and throat paler; the wing-coverts and secondaries blackish, margined with brownish white; the primaries blackish, slightly margined with yellow; the tail blackish white-margined, with the outer feathers nearly wholly white; beneath the body yellowish white, streaked with brown on the breast and flanks: and the space from the nostrils reaching to behind the eyes and cheeks, yellowish. Habitat, East Falkland Island (_March_), and Tierra del Fuego (_February_). [Illustration: _Birds. Pl. 33._ _Chlorospiza Xanthogramma._ ] [Illustration: _Birds. Pl. 34._ _Tanagra Darwinii._ ] This species is common at the Falkland Islands, and it often occurs mingled in the same flock with the last one. I suspect, however, it more commonly frequents higher parts of the hills. These species have a very close general resemblance; but the marks about the head, which are white in the _C. melanodera_, are yellow in the _C. xanthogramma_, while the parts of the tail-feathers which are white in the latter, are yellow in the _C. melanodera_: this difference of colours does not hold in the females, but they may be at once distinguished by the greater length of wing, when folded, of the _C. xanthogramma_. CHRYSOMITRIS MAGELLANICA. _Bonap._ Fringilla Magellanica, _Vieill._ Ency. Meth. 983; Ois. Chant. de la Zône Torride, pl. 30; Audubon, Birds of Am. pl. 394, f. 2. Gafarron, _Azara_, No. 134. Fringilla icterica, _Licht._ Cat. p. 26. This bird was very abundant in large flocks during May, at Maldonado; I found it also at the Rio Negro. SUB-FAMILY.—TANAGRINÆ. PITYLUS SUPERCILIARIS. Tanagra superciliaris, _Spix._ Av. Sp. Nov. 2. t. lvii. fig. 1. p. 44. My specimen was procured from Santa Fé, in Lat. 31° S. 1. AGLAIA STRIATA. _D’Orb. & Lafr._ PLATE XXXIV. ♂ Tanagra striata, _Gmel._ Syst. 1. 899; Ency. Meth. 776; _Licht._ Cat. p. 31. Sp. 347; Proc. Zool. Soc. 1837, p. 121, pl. 34 of this work. L’Onglet, _Buff._ iv. p. 256. Le Lindobleu, dore et noir, _Azara_, No. 94. ♀ Tanagra Darwinii, _Bonap._; Proc. Zool. Soc. 1837, p. 121. I saw the only specimen, which I procured, feeding on the fruit of an opuntia at Maldonado.