Volume I Part 1 (2/2)

In the next order, Steganopodes, the Argentine Ornis seems to be very deficient. Out of the five families of this group which occur in the Neotropical Region, one only is yet known to us to be represented in the Argentine Ornis, and that by a single species. But when the sea-birds of the Argentine coast-land come to be better known, there is no doubt that several additions will be made to the list.

The next following order, Herodiones, is of much more importance in Argentine Ornithology, not less than 19 species of this group being already known to exist within our limits, out of a total of 44 Neotropical species. And amongst these we can pick out the little Variegated Bittern (_Ardetta involucris_) and the four species of Ibises as being highly characteristic members of the Argentine Ornis.

The tenth order, that of Anseres, or Waterfowl, commonly so-called, is also largely in excess as regards the number of species. Out of a total of 64 Anseres belonging to the Neotropical Regions, 23 are met with in the Argentine Republic. Moreover, the greater number of these are exclusively Antarctic species, restricted to the Patagonian Subregion.

Amongst them we may specially call attention to the Black-necked Swan (_Cygnus nigricollis_), the Chiloe Wigeon (_Mareca sibilatrix_), and the Rosy-billed Duck (_Metopiana peposaca_) as highly characteristic and ornamental species.

Proceeding to the next order, that of the Pigeons (Columbae), we find the number of Argentine species to be slightly below the average. Several fine Pigeons and Doves are well-known inhabitants of the Republic, but the Columbine order is not a prominent one within our limits.

The Gallinaceous birds of the Neotropical Region are about ninety in number, the greater part of these belonging to the Cura.s.sows, Cracidae, a family specially adapted for habitation in the extensive forests of the New World. Four species of Cracidae have been met with in the forest-region of Northern Argentina; but the Gallinaceous group as a whole must be held to be deficient in this part of South America, the place in Nature which these birds fill in other regions being occupied here by the more lowly organized Tinamous, of which we shall speak further on.

The Geranomorphae of the Argentine Republic are much in excess as regards the number of species. This arises mainly from the abundant supply of Rails and Crakes which Nature has provided for the more swampy districts of the pampas, and to the presence of no less than three distinct species of Coots (_Fulica_), which appear to be generally abundant on the lakes and pools. Nor must we forget to mention as of special interest the two Cariamas which belong to this order, and which are the only representatives of a family of very peculiar structure. One of the two Cariamas is, so far as we know, absolutely confined to the Northern provinces of the Argentine Republic; the second is a bird of the campos of Southern Brazil, which only just comes within our limits.

The Snipes and Plovers and their allies, const.i.tuting the Order Limicolae, 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 Thinocoridae or Seed-Snipes, of which two species occur within our limits.

Of the Gaviae, 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 lat.i.tudes. 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.

Lastly, we come to the final order of the Neotropical Ornis in the shape of the Rheas, or the American representatives of the Ostrich-type of bird-life. The Rhea is, above all other birds, a most characteristic representative of the Avifauna of the Patagonian subregion. It is true that it ranges far north throughout the campos of Inner Brazil, where the outlying members have become developed into an almost distinct species or subspecies, _Rhea americana macrorhyncha_. But south of the Rio Negro of Patagonia another very distinct type of Rhea, almost subgenerically different, is met with and extends thence to the Straits of Magellan. _Rhea_ has also been lately ascertained to occur on the western side of the Andes in the Chilian province of Tarapaco; so that this fine form of bird-life is diffused nearly over the entire Patagonian subregion, and is well ent.i.tled to be termed one of the most characteristic features of the Patagonian Avifauna.

In conclusion, therefore, we may sum up our present knowledge of the Argentine Avifauna somewhat as follows:--

The Argentine Avifauna comprises 434 species of birds, referable to 54 families and genera.

All the twenty Orders of the Neotropical Avifauna have representatives within its boundaries, except the _Opisthocomi_ or Hoatzins, which are restricted to the Amazonian subregion.

The most numerous families of the Argentine Avifauna are, among the Pa.s.seres, the Finches with 46 species, the Tyrants with 63 species, and the Wood-hewers with 46 species. Among the remaining Orders, the Diurnal Birds of Prey with 19 species, the Waterfowl with 22 species, the Rails with 13 species, the Snipes with 15 species, and the Tinamous with 8 species, are likewise well represented.

Genera characteristic and proportionately numerous in species in the Argentine Avifauna are _Poospiza_ and _Phrygilus_ among the Finches, _Taenioptera_ and _Cnipolegus_ among the Tyrants, _Synallaxis_ among the Wood-hewers, _Fulica_ among the Rails, and _Nothura_ among the Tinamous.

Less numerous in species, but highly characteristic forms of the Argentine Ornis, are _Thinocorus_, _Rhynchotis_, and _Rhea_.

The following ten genera, mostly monotypic, are, so far as we know at present, restricted to the limits of the Argentine Avifauna or its immediate confines:--_Donacospiza_ and _Saltatricula_ (Fringillidae); _Coryphistera_, _Anumbius_, _Limnornis_, and _Drymornis_ (Dendrocolaptidae); _Rhinocrypta_, with two species (Pteroptochidae); _Spiziapteryx_ (Falconidae); _Chunga_ (Cariamidae); and _Calodromas_ (Tinamidae).

ARGENTINE ORNITHOLOGY.

Order I. Pa.s.sERES.

Suborder I. _OSCINES._

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