INTRODUCTION. xxiii 



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 sub- 

 generically 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 entitled 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 represen- 

 tatives 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 Passeres, 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, 

 Tcenioptera and Cnipolegus among the Tyrants, Synallaxis among the 

 Wood-hewers, Fulica among the Rails, and Nothura among the Tina- 

 mous. Less numerous in species, but highly characteristic forms of the 

 Argentine Ornis, are Thinocorus, Rhynchotis, and Rhea. 



