The Snipes and Plovers and their allies, constituting the Order Limicolæ, are again in excess in the Argentine Avifauna, not less than 25 out of a known total of 73 Neotropical species having been already met with within our limits. A large proportion, however, of these birds are merely winter visitors, and breed only in the far north. On the other hand, the Slender-billed Plover (_Oreophilus ruficollis_) and the Winter Plover (_Eudromias modesta_) are species highly characteristic of the Patagonian subregion, and come to the neighbourhood of Buenos Ayres from a contrary direction. Another especially characteristic Patagonian family of this order is the Thinocoridæ or Seed-Snipes, of which two species occur within our limits. Of the Gaviæ, or Gulls and Terns, of the Argentine Republic, nine species are already known out of a total of 53 Neotropical members of the group, and additions no doubt will be made to the list when the coast-birds of La Plata come to be better known. The seventeenth order of Birds, Pygopodes, is represented in the Argentine Ornis by five species of Grebes. Two of these are widely diffused over all America, the remaining three are Antarctic species belonging to the Patagonian subregion. As only nine species of this groups are known to occur in the whole Neotropical Region, the Pygopodes are highly in excess in the Argentine Avifauna. The Impennes, or Penguins, which form the eighteenth order of birds, according to the arrangement of the 'Nomenclator,' are a group specially characteristic of high Antarctic latitudes. Nine species of Penguins occur on the coasts of Antarctic America, but one of these only is as yet known to reach so far north as our limits. We now come to the Crypturi or Tinamous, an order of birds commonly supposed to be Gallinaceous, and generally confounded with "Partridges" and "Pheasants" in the vernacular. They are, however, in some points of essential structure more nearly allied to the Struthiones, although they doubtless fill the same place in the economy of Neotropical Nature as the true Gallinaceous birds in other lands. The Tinamous are spread all over the Neotropical Region and number about 36 species. Eight of these occur within the Argentine Republic; and amongst them we may pick out the Martineta Tinamou (_Calodromas elegans_) and the three species of the genus _Nothura_ as being specially characteristic Patagonian types.