This goose is common in Tierra del Fuego, the Falkland Islands, and on the western coast, as far north as Chiloe. It is called by the sailors the “rock goose,” as it lives exclusively on the rocky parts of the sea-coast. In the deep and retired channels of Tierra del Fuego, the snow-white male, invariably accompanied by his darker consort, and standing close by each other on some distant rocky point, is a common feature in the landscape. Mr. Eyton has described the treachea of this species, which I brought home. [Illustration: _Birds. Pl. 50._ _Anser melanopterus._ ] PÆCILONITTA BAHAMENSIS. _Eyton._ Pæcilonitta Bahamensis, _Eyton_, Monog. p. 116. Anas Bahamensis, _Linn._ Syst. i. 199. Mareca Bahamensis, _Steph._ Gen. Zool. xii. p. 137. A specimen was procured from a small salt-water lagoon in the Galapagos Archipelago (_October_.) It was a male; bill, lead colour; base of superior mandible purple, with a black mark in the upper part. DAFILA UROPHASIANUS. _Eyton._ Dafila urophasianus, _Eyton_, Monog. Anatidæ. p. 112. Anas urophasianus, _King_, Zool. Journ. iv. 351. Bahia Blanca, Northern Patagonia. RHYNCHASPIS MACULATUS. _Gould._ Rhynchaspis maculatus, _Gould_, in Jard. & Selby Illust. Orn. p. 147. pl. 147. Mr. Gould observes that, “A good figure of this beautiful shoveller may be found in the 3rd vol. of Messrs. Jardine and Selby’s Illustrations of Ornithology. Their figure was taken from an example which I forwarded to those gentlemen with the name of _maculata_ attached: my specimen was received from the Rio Plata, and this is also the locality whence (in October) Mr. Darwin’s specimen was procured. The numerous and conspicuous spots distributed over the body, renders this species readily distinguishable from all the other members of the genus.” 1. QUERQUEDULA ERYTHRORHYNCHA. _Eyton._ Querquedula erythrorhyncha, _Eyton_, Monog. Anatidæ, p. 127. Anas erythrorhyncha, _Spix_, Av. Nov. sp. pl. My specimens were obtained from Buenos Ayres (_October_) and the Straits of Magellan (_February_.) 2. QUERQUEDULA CRECCOÏDES. _Eyton._ Querquedula creccoïdes, _Eyton_, Monog. Anatidæ, p. 128. Anas creccoides, _King_, Zool. Journ. iv. 99. Mr. Gould observes that, “This species was first described by Mr. Vigors, from a specimen in the collection brought from the Straits of Magellan, by Capt. P. P. King. It is a true teal, and in size and form closely assimilates to the common teal of Europe, and to the species inhabiting North America (_Querquedula Carolinensis_, Bonap.) to both of which it is evidently an analogue, and doubtless represents those birds in the southern half of the American continent.” My specimens were procured from the Rio Plata, and from the Straits of Magellan. MICROPTERUS BRACHYPTERUS. _Eyton._