18 
FALCO DISPAR. 
error in representing 1 tlie feet of the swallow-tailed 
hawk. Of what consequence, will it perhaps be said, 
is the form of the scales covering the foot of a hawk ? 
But these afford precisely one of the best representative 
characters of groups, and it will, therefore, not be 
thought unnecessary to caution artists in this, and 
similar cases. 
The young, as described by Temmmek, rs in a more 
advanced stage of plumage-7 the front, forepart of the 
neck, thighs; flanks, and under tail-coverts are pure 
white ; the breast and belly are of the same colour, but 
are marked with reddish spots, and brown lines ; the 
occiput, nucha, back, and scapulars are brownish, mixed 
with whitish, and more or less tinged with cinereous; 
all these feathers having wide margins of whitish and 
reddish ; the upper tail-coverts are black, with reddish 
margins ; the inferior marbled with black and white ; 
the quills are bluish, terminated with white ; the tail 
is of a grayish white, with black shafts ; all the feathers 
have dark cinereous towards the point, and are tipped 
with white. 
This species is an inhabitant of a great portion of the 
American continent, as the Alcon bianco of Paraguay, 
so w r ell described by D’Azara, is undoubtedly the same 
bird. Vieillot undertook to classify it from B’Azara’s 
description, applying to it the name of Milvus leucurus ; 
but, after more attentive consideration, he perceived 
that it was not a Milvus , but an Elanus. He conse- 
quently removed it to that genus, which he called 
Elanoides , at the same time asserting, that with the 
swallow-tailed hawk, it ought to constitute a different 
section from the black-winged hawk; from which, 
upon actual comparison, it is with difficulty shown to 
be even specifically distinct ! Such are the absurdities 
into which authors are betrayed through the highly 
reprehensible practice to which some are addicted, of 
attempting to classify and name animals they have 
never seen, from the descriptions, or mere indications, of 
travellers. Though, by such means, they may some- 
times gain the credit of introducing a new species, and 
