Owing to the excessive roughness of the weather, our passage from Rio Janeiro to the Bay of Conception afforded us but few opportunities to add to our collections. A snipe blown out to sea from the Rio de la Plata, a specimen of _Diomedea Albatros_ at Terra del Fuego, a large _Salpa_, and a _Lepas_, were all we were able to obtain. The Bay of Conception presents a rich field to the ornithologist. A kind of parrot, with a long tail, and naked round the eyes, flies about in swarms; and a smaller kind from the interior, is to be found tame in the houses; our guns frequently brought down two small kinds of doves. Of _Ambulatores_ we met some, of the genera _Cassicus_, _Motacilla_, _Muscicapa_, _Pyrgita_, _Saxicola_, _Cotile_; of birds of prey, _Percnopterus Jota Mol._, and two buzzards; of _Grallatores_, two kinds of _Haematopus_, both with white legs, the one with a black body, as _H. niger_ is described by Quoy and Gaimard, the other more similar to the European; a _Vanellus_ with spurs to the wings, _Numenius_, _Scolopax_, _Phalaropus_, _Ardea Nycticorax_; and lastly a small bird with remarkably short legs, digitated, and with a short thick bill, frequenting the sea-shore, and feeding on seeds of _Rumex_ and _Polygonum_, and constituting a new species, which may be called _Thinocorus_. Of aquatic birds, there were two kinds of _Sterna_ and _Larus_; many thousands of _Rynchops nigra_, which were so numerous as to appear like clouds when they rose into the air; a _Procellaria_ of the variety _Nectris_; two kinds of _Podiceps_, and an _Aptenodytes_ of the variety _Spheniscus_. The upper part of the latter was of a lead colour, and the lower part white, with a line of dullish grey running from the bill to the belly, and forming a boundary between the two colours; the bill and legs quite black. The animal was alive when brought to us. When resting, it lay upon its belly and stretched out its head. In the water it appeared unable to maintain itself afloat except by incessant paddling, the whole of the body being meanwhile under water. Of amphibia, only five kinds can be distinctly named; a brown _Coluber_, two small lizards of the family of _Scincoidea_, a small _Rana_, with a spot like an eye on the belly, and a small _Bufo_. Of fishes, the most remarkable was a _Torpedo_, with the back of a reddish brown, and smooth; and a _Callorhynchus antarcticus_: the latter may very well remain in the class of _Chimaera_. Of crustaceae, we collected three _Canceres_, a _Portunus_, a _Porcellana_, a _Sphaeroma_, and a _Ligia_.