xxii INTRODUCTION. 



distinct species of Coots (Fulicd), 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, constituting the Order Limi- 

 colse, 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 Thinocoridse or Seed-Snipes, of which two 

 species occur within our limits. 



Of the Gavise, 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 

 group are known to occur in the whole Neotropical Region, the Pygo- 

 podes 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 com- 

 monly 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 Struthi- 

 ones, although they doubtless fill the same place in the economy of 

 Neotropical Nature as the true Gallinaceous birds in other lands. The 



