We have seen in a preceding chapter that the great terrestrial and aquatic birds ("Waders") of the wild plains of the Ancient World have few analogues in America, and that the small number of genera which are represented therein are represented by much smaller species. I have cited the Ostrich and the Phenicopterus. The American Ostrich, or Nandou (_Rhea_), is not above half the size of his African congener, from which he differs in having the feet three-toed, and each toe armed with a claw. Moreover, his head and neck are more fully clothed with plumage; the wings are plumed, and more perfectly developed; and he is tailless. The neck has sixteen vertebræ. Though endowed with more perfect wings than the Ostrich of Africa, he is nevertheless incapable of flight, representing another grade in Nature's slow ascent from the wingless bird to the bird possessed of full powers of flight. He inhabits the wide grassy plains of South America below the Equator, and as far south as latitude 42°. He is never seen across the Cordilleras, but roams in great numbers the banks of La Plata and its tributaries. He is generally seen in small troops. There are at least three species: the _Rhea Americana_, about five feet high; the _Rhea macrorhyncha_, distinguished by its large bill; and the _Rhea Darwinii_, the smallest, which inhabits Patagonia. The Flamingoes proper to the New World are: the Red Flamingo, all whose plumage glows with a more or less vivid red; and the Fiery Flamingo, probably only a variety of the preceding. Both are natives of the dreary Patagonian desert, of Chili, and some other southern districts. [Illustration: 1. Cathartes-Urubu. 2. King of the Vultures.]