380 
WHITE- TAILED HAM K. 
US to follow Temminck’s course, in wliich we should never 
have ventured to take the lead. This character consists in the 
tail being, in Falco dispar^ constantly irregular, while in F, me- 
lan'opterus, 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 conspicuous in Tem- 
minck’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 supposed instances, 
always rare, and daily diminishing upon more critical observa- 
tion, 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 iden- 
tical, this adventurous journey must have been performed. 
For, even admitting several centres of creation, we cannot 
believe that nature,* who, notwithstanding her luxuriant 
abundance, evidently accomplishes all her ends with the great- 
est economy of means, has ever placed, aboriginally, in differ- 
ent parts of the globe, individuals of the same species ; but has 
always given to each the power of extending its range accord- 
ing to volition, in any direction where it should find climate, 
food, or other circumstances most appropriate. 
The white-tailed hawk is one of those anomalous species, 
which connect the generally received divisions of the great 
'* The word nature being taken in so many different acceptations, we think 
proper to state, that with Ranzani, we mean by it “ the aggregate of all created 
beings, and of the laws imposed on them by the Supreme Creator.” 
