Note 48 — Family FALCONIDÆ.—The Falcons.
Reading edition
Falco gyrfalco, var. gyrfalco (Linn.). Falco gyrfalco, Linn. S. N. 1766, p. 130.—Gmel. S. N. 275.—Schleg. Rev. Crit. II, Tr. de Fauc. pl. iii; F. van Nederl. Vog. pls. iii and iv.—Naum. Vog. pl. cccxci. Hierofalco gyrfalco, Schleg. Bonap. Rev. Zool. 1854, 535.—Newton, Oötheca Wolleyana, I, 87, pl. c. F. gyrfalco norvegicus, Wolley. Falco gyrfalco norwegicus, Schleg. Mus. Pays-Bas, 1862, 12. Falco candicans, var. γ, Blas.
Wing, 13.00–14.50; tail, 9.30; culmen, .98; tarsus, 2.50; middle toe, 1.92.