“Beagle” generally called it either by this name, or from its larger size by that of _Carrancha_,—both names, however, plainly indicating its close and evident relationship with the birds of that family. The craw is feathered; and does not, I believe, protrude like that of the _P. Brasiliensis_ or _M. leucurus_. It builds in trees, and the female was just beginning to lay in October. The bird of which the full figure has been given, is a young female, but of, at least, one year old. The old male bird is of a uniform dusky plumage, and is seen behind. The adult female resembles the young of the same sex, but the breast is dark brown like that of the male. In precisely the same manner as was remarked in the case of the _M. leucurus_, these old females are present in singularly few proportional numbers. One day at James’ Island, out of thirty birds, which I counted standing within a hundred yards of the tents, under which we were bivouacked, there was not a single one with the dark brown breast. From this circumstance I am led to conclude that the females of this species (as with the _M. leucurus_) acquire their full plumage late in life. 1. BUTEO ERYTHRONOTUS. Haliaëtus erythronotus, _King_, in Zoological Journal, vol. iii. p. 424. Buteo tricolor, _D’Orbigny_. I obtained specimens of this bird from Chiloe and the Falkland Islands, and Captain King who first described it, procured his specimens from Port Famine, Lat. 53° 38′ in Tierra del Fuego. M. D’Orbigny states that it has a wide range over the provinces of La Plata, central Chile, and even Bolivia; but in this latter country, it occurs only on the mountains, at an elevation of about 12,000 feet above the sea. The same author states, that it usually frequents open and dry countries; but as we now see that it is found in the dense and humid forests of Chiloe and Tierra del Fuego, this remark is not applicable. At the Falkland Islands, it preys chiefly on the rabbits, which have run wild and abound over certain parts of the island. This bird was considered by Captain King as a _Haliaëtus_; but Mr. Gould thinks it is more properly placed with the Buzzards. Captain King gave it the appropriate specific name of _erythronotus_, and, therefore, as Mr. Gould observes, the more recent one of _tricolor_, given by M. D’Orbigny, must be passed over. 2. BUTEO VARIUS. _Gould._ Buteo varius, _Gould_, Proceedings of the Zoological Society, Part v. 1837, p. 10.