14 
FALCO DISFAR. 
our American specimens, and others from Africa and 
Java. They agreed perfectly, especially with that from 
Java, in every, the minutest character, even feather by 
feather, much better than birds of prey of the same 
species, and from the same country, do generally. They 
are even more alike than different specimens from the 
Old Continent of the black-winged itself, since that 
species is said to vary considerably in the black markings, 
which extend more or less on the wings in different 
individuals. Nevertheless, a constant, though trivial, 
differential character, added to the difference of locality, 
has induced us to follow Temminck’s course, in which 
we should never have ventured to take the lead. This 
character consists in the tail being in Falco dispar 
constantly irregular, while in F. melanopterus , it is 
even ; or to explain it more clearly, the outer tail- 
feather is rather the longest in the African, and more 
than half an inch shorter than the next in the American 
species. This essential character is much more con- 
spicuous in Temminck’s plate than in ours, owing to 
the tail being spread. In the black-winged, also, the 
lower wing-coverts are destitute of the black patch so 
conspicuous in the American bird ; a female from Java 
has, however, a slight .indication of it, but no trace of 
it is observable in our African males. 
By admitting this to be a distinct species from the 
black- winged hawk, we reject one more of those sup- 
posed instances, always rare, and daily diminishing 
upon more critical observation, of a common habitation 
of the same bird in the warm parts of both continents, 
without an extensive range also to the north. A 
steady and long protracted exertion of its powerful 
wings, would have been requisite to enable it to pass 
the vast and trackless sea which lies between the 
western coast of Africa, the native country of the 
black-winged hawk, and the eastern shores of South 
America. Yet were the species identical, this adven- 
turous journey must have been performed. For, even 
admitting several centres of creation, we cannot believe 
