298 BLUE HAWK, OR HEN-HARRIER. 
the adult female (which is not the case in the ash-coloured 
harrier), being, however, more varied with rusty, and easily 
distinguished by its smaller size, It is in this state that Wil- 
son has taken the species, his very accurate description being 
that of a young female. The male retains this plumage until 
he is two years old, after which he gradually assumes the grey 
plumage peculiar to the adult: of course they exhibit almost 
as many gradations as specimens, according to their more or 
less advanced age. ‘The ash and white appear varied or min- 
gled with rusty ; the wings, and especially the tail, exhibiting 
more or less indications of the bands of the young plumage. 
The male, when he may be called already adult, varies by 
still exhibiting the remains of bands on the tail, more or less 
marked or obliterated by the yellowish edges of the feathers 
of the back and wings, and especially by retaining on the 
hind head a space tinged with rusty, with blackish spots. 
This space is more or less indicated in the greater part both 
of the American and European specimens I have examined. 
Finally, they are known by retaining traces of the yellowish 
of the inferior surface, in larger or smaller spots, chiefly on the 
belly, flanks, and under tail-coverts. 
For the greater embellishment of the plate, we have chosen 
to represent one of these very nearly but not quite adult males, 
in preference to a perfectly mature bird, which may easily be 
figured to the mind by destroying every trace of spot or bar. 
It is, moreover, in this dress that the adult is met with in the 
middle and northern States, where it is very rare, and we 
have never seen a specimen quite mature, though the young 
are tolerably common; as if the parents sent their children on 
a tour to finish their education, then to return and marry, and 
remain contentedly at home. ‘The specimen here figured was 
shot on Long Island, and was preserved in Scudder’s Museum, 
New York. 
Its total length is eighteen inches ; breadth, forty-one; the 
bill, bluish black; cere, irides, and feet, yellow; claws, black. 
The plumage above is bluish ashy, much darker on the scapu- 
