The American Vultures, or Condors as it is better to call them, are
now universally admitted to be quite distinct from the rest of the
Accipitres and to constitute a family apart. They differ from the
Falconidæ in having the hind toe inserted at a higher level than the
others, and in the nostrils being pervious, owing to the absence of the
bony septum, besides in other important characters[2].
[2] _Cf._ Standard Nat. Hist. vol. iv., Birds, p. 266 (Boston, 1885).
The Cathartidæ are few in number, only some six or seven species being
accurately known. Of these, three occur within the limits of the
Argentine Republic.