This Dove, which is a southern form of a widely distributed group of species of the genus _Engyptila_, formerly called _Leptoptila_, inhabits the woods of the Plata district, and never, like other Pigeons, seeks the open country to feed. It is solitary, although, where many birds live in close proximity, three or four may be sometimes seen in company. It spends a great deal of time on the ground, where it walks about under the trees rather briskly, searching for seeds and berries. Their song is a single uninflected and rather melodious note, which the bird repeats at short intervals, especially in the evening during the warm season. Where the birds are abundant the wood, just before sunset, becomes vocal with their curious far-sounding notes; and as this evening song is heard as long as the genial weather lasts, it is probably not related to the sexual instinct. The nest is a simple platform; the eggs are two and white, but more spherical in shape than those of most other Pigeons. Order XII. GALLINÆ. Fam. XLII. CRACIDÆ, or CURASSOWS. Of the great Order of Gallinaceous Birds, so useful to mankind, two forms only are found in South America--the Toothed Partridges (_Odontophorinæ_) and the Curassows (_Cracidæ_). No member of the former group has as yet been ascertained to occur in Argentina; and of the Curassow family (one of the most characteristic types of Neotropical forest-life) only four species are with certainty known to be found within our limits out of a total of some fifty known species. But the Cracidæ are essentially tree-birds, and can only be looked for in forest-countries. 365. CRAX SCLATERI, G. R. Gray. (SCLATER'S CURASSOW.) +Crax alector+, _Burm. La-Plata Reise_, ii. p. 500. +Crax sclateri+, _Gray, List of Gallinæ_, p. 14 (1867); _Scl. Trans. Zool. Soc._ ix. p. 28, pls. xliv. & xlv.; _Burm. P. Z. S._ 1871, p. 702. _Description._--Black; lower belly and tips of tail-feathers white; lores naked; cere and bill yellow; feet flesh-colour: whole length 32·0 inches, wing 14·0, tail 14·0. _Female_: above black, with buffy cross bars; crest white, barred with black: beneath, throat black, breast more or less barred with black; abdomen ochraceous; tail black, with buffy-white bars and tips. _Hab._ Paraguay and N. Argentina. Azara described both sexes of this Curassow under the name of "El Mitu" (Apunt. iii. p. 83), but, along with other authors, confounded it with the Crested Curassow of Guiana (_Crax alector_). In Paraguay it is said to be numerous, but in Argentina only occurs on the northern and eastern frontiers (in Tucuman and Misiones), where it frequents the forests. 366. PENELOPE OBSCURA, Temm. (DARK GUAN.) +Penelope obscura+, _Scl. et Salv. Nomencl._ p. 136; _iid. P. Z. S._ 1870, p. 525; _Barrows, Auk_, 1884, p. 275 (Entrerios). +Penelope boliviana+, _Burm. P. Z. S._ 1871, p. 701 (Tucuman)? +Penelope pileata+, _White, P. Z. S._ 1882, p. 627 (Catamarca)?