AQUILA.—SPIZAETUS. 91 
come nearer the Buzzards (Buteo) than to other members of: the family, being, in fact, 
larger and stronger representatives of them, and connected in a measure by such 
intermediate forms as Misaetus, Spizaetus, &c. 
The tarsus is closely feathered to the base of the toes, and the tibie are furnished 
with long feathers; the toes are reticulate for the most part above, and the outer and 
middle ones are connected by a web at the base. ‘The bill is very large and strong, the 
nostril oval and oblique, the superciliary bone prominent. Wings long and pointed, 
the third to the fifth quills the longest, the second to the sixth sinuate on the inner 
webs. Tail rounded. Feathers of the occiput and nape lanceolate. 
1. Aquila chrysaetus. 
Falco chrysaetus, Linn. Syst. Nat. i. p. 123°. 
Aquila chrysaetus, Swains. Faun. Bor.-Am. Birds, p. 127; Coues, Birds N. W. p. 368°; Sharpe, 
Cat. Birds Brit. Mus. i. p. 235*; Bendire, Life Hist. N. Amer. Birds, 1. p. 263, t. 9. 
figs. 8,5°; Fisher, Bull. U. S. Dep. Agr. no. 3, p. 93, t. 13°. 
Falco canadensis, Gm. Syst. Nat. i. p. 256%. 
Aquila canadensis, Cassin, in Baird’s Birds N. Amer. p. 41°; Dugés, La Nat. i. p. 138°. 
Aguila sp., Swains, Phil. Mag. new ser. i. p. 866”. 
Saturate fusca, nucha et: cervice postica fulvis, humeris et campterio quoque fulvis, tarsis plumosis fuscis ; 
caude bitriente basali pallide fusco variegata ; rostro corneo, digitis flavis. Long. tota circa 34:0, ale 25-0, 
—caudee 13:0, tarsi 4:0. (Descr. maris ad. ex Ciudad in Durango, Mexico. Mus. nostr.) 
Hab. Northern portions of Northern Hemisphere and in mountainous regions further 
south.—Mexico (Bullock }°), Ciudad in Durango (forrer), Guanajuato (Dugeés ®). 
It was probably to an Eagle of this species that Swainson referred in his paper on 
Bullock’s Mexican birds published in 1827, but to which he did not give a specific 
name. Dugés includes A. chrysaetus in his list of Guanajuato birds, and its presence 
in the Cordillera between Durango and the Pacific Ocean is made certain by a fine 
specimen obtained and sent to us by Mr. A. Forrer on 20th October, 1881. 
The bird is probably found, though perhaps sparingly, throughout the Sierra Madre 
of North-western Mexico, and is there at the extreme southern limit of its range. 
In North America it has a very wide distribution over the mountainous portions of 
the temperate region, and is found in similar situations in the Old World. 
At one time the western bird was sought to be separated under the name of Aquila 
canadensis. but no such distinction can, in our opinion, be maintained. 
The habits of this well-known Eagle have been fully described in so many works that 
they need not be mentioned here. 
SPIZAETUS. 
Spizaetus, Vieillot, Anal. p. 24 (1816) ; Sharpe, Cat. Birds Brit. Mus. i. p. 259. 
Of the ten species of Spizaetus included in the British Museum ‘Catalogue’ only 
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