A History of North American Birds; Land Birds; Vol. 3 of 3

by Spencer Fullerton Baird; T. M. Brewer; Robert Ridgway

A comparison of the American birds with series of sixteen European specimens shows constant differences in the birds of the two continents,—quite enough to establish a difference of race, although not of specific value. The European bird is much the darker beneath, the blackish-brown spots on jugulum and breast being blended, or suffused, so as to give the predominating tint to this region.

These differences, though constant and quite appreciable on comparison, are very slight, while the proportions are about the same. A young specimen of the European style differs from American in entire absence of rufous tinge to white of head, neck, and lower parts, less complete band across the abdomen, immaculate white ear-coverts, cheeks, and throat; the tibiæ and tarsi are also much more thickly spotted than in the American young; there is also more white on base of outer surface of primaries.

List of Specimens examined.—Nat. Mus., 6; Philad. Acad., 8; Bost. Soc., 2. Total, 16.

Measurements.—♂. Wing, 16.00; tail, 8.70; culmen, .80; tarsus, 2.30; middle toe, 1.30. Specimens, 1. ♀. Wing, 18.20; tail, 9.75; culmen, .95; tarsus, 2.60; middle toe, 1.50. Specimens, 1.

[⁹²] Aquila chrysaëtus, var. chrysaëtus (Linn.). Aquila valeria, Albin, B, II. pl. ii. Aquila chrysaëtus, Briss. Orn. I, 431, et Auct. Falco chrysaëtus, Linn. S. N. 1760, 125. Aquila melanaëtus, Briss. Orn. I, 434. Falco melanaëtus, Linn. S. N. 124. Aquila regia, Less. Tr. Orn. Falco fulvus, Linn. S. N. 1760, 125 (young).

List of Specimens examined.—Nat. Mus., 4; Philad. Acad., 14; Bost. Soc., 2; Mus. Cambridge, 1; Mus. J. C. Sharp, Jr., 1. Total, 22.

Measurements.—♂. Wing, 23.80–24.30; tail, 14.00–14.50; culmen, 1.68–1.70; tarsus, 3.40; middle toe, 2.40–2.45. Specimens, 2. ♀. Wing, 25.00–25.50; tail, 14.00–14.50; culmen, 1.80–1.85; tarsus, 3.80–4.10; middle toe, 2.85–3.10. Specimens, 3.

[⁹³] Haliaëtus pelagicus (Pall.). Falco pelagicus, Pallas, Zoog. Ros. As. I, 343, pl. ix. Aquila p., Kittl., Boie. Haliaëtus p., Sieb., Gray, Cass. B. Cal. & Tex. I, pp. 31, 110, pi. vi (♀); Ib. Birds N. Am. 1858, 42. Thalassoaëtus, Kaup, Jard. Falco leucopterus, Temm. Falco imperator, Kittl. Hab. Northeastern Asia, Japan (Siebold); Kamschatka.

[⁹⁴] Established by Vigors, in 1825.

[⁹⁵] From the Vulturinæ are excluded the genera Gypætus and Neophron, each of which probably constitutes a subfamily by itself.