AQUILA.— SPIZAETUS. 91 



come nearer the Buzzards (Suteo) 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 Nisaetus, Spizaetus, &c. 



The tarsus is closely feathered to the base of the toes, and the tibiae 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. 135 '. 



Aquila chrysaetus, Swains. Faun. Bor.-Am. Birds, p. 12"; Coues, Birds N. W. p. 368' ; Sharpe, 



Cat. Birds Brit. Mus. i. p. 235*; Bendire, Life Hist. N. Amer. Birds, i. p. 263, t. 9. 



figs. 3, 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 ° ; Duges, La Nat. i. p. 138 '. 

 Aquila sp.. Swains. Phil. Mag. new ser. i. p. 366 ^''. 



Saturate fusca, nucha et cervice postica fulvis, humeris et oampterio quoque fulvis, tarsis plumosis fuseis ; 

 caudee bitriente basali pallide fusco variegata ; rostro corneo, digitis flavis. Long, tota circa 34'0, alae 25'0, 

 caudae 13"0, tarsi 4*0. (Descr. maris ad. ex Ciudad in Durango, Mexico. Mus. nostr.) 



Bab. Northern portions of Northern Hemisphere and in mountainous regions further 

 south. — Mexico {BullocJc^^), Ciudad in Durango (Forrer), Guanajuato {Buges^). 



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. Duges 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. 2i (1816) ; Sharpe, Cat. Birds Brit. Mus. i. p. 259. 



Of the ten species of Spizaetus included in the British Museum ' Catalogue ' only 



12* 



