94 Bidgway on the Plumage of G-yrfalcons. 
parts with dark brownish slate largely predominating, the creamy white 
forming longitudinal stripes on the middle of the breast and abdomen, 
smaller, irregular spots on the sides of the breast, large, transverse, 
oblong spots (forming interrupted bands) on the flanks, and regular, 
sharply defined, transverse bands on the crissum ; anal region nearly 
uniform dusky. Axillars and lining of the wing dark brownish slate, 
marked with roundish spots of pale cream-color; under surface of the 
primaries and tail silvery slate, with indications of bars, in the form of 
transverse, oblong spots, of mottled pale grayish. Wing, 16.25; tail, 9.25; 
culmen, 1.00; tarsus, 2.50 (bare portion, .90); middle toe, 2.10. 
The Labrador Gyrfalcon represents the darkest phase of the 
Falco gyrfalco of Linnaeus, or the opposite extreme of color-variation 
from the white race known as F. candicans , Gmel. It may, in most 
cases, be readily distinguished from the race of the same species 
inhabiting the interior districts of British America and the Arctic 
coast, by the darker and much more uniform colors, with dusky 
largely prevailing on the lower parts, in both old and young. To 
the more northern form the name sacer, Forster, unquestionably 
belongs, every point of Forster’s diagnosis applying unmistakably 
to it, even the yellow irides, since it appears, if we may trust the 
word of collectors, that the Arctic American Gyrfalcon not unfre- 
quently does have the eyes yellow! Forster having applied the 
name sacer to this species in 1772, it follows that this term cannot 
be used for the Old World species usually thus designated ( Falco 
sacer , Gmel., S. N. I. ii, 1788, 273, based on Le sacre of Brisson 
and Buffon), for which the name lanarius, Pall. (Zoog. Bosso-As., I, 
1831, 330), next in order of date, appears to be the proper appel- 
lation. 
As to the claims of this Arctic American form to recognition as 
a definable race, a few words may not be out of place here. In 
“History of North American Birds,” Yol. Ill, p. 117, I stated that 
the var. sacer, as there restricted, was nearly intermediate in its 
characters between var. islandicus and var. gyrfalco , some specimens 
approaching very closely to either form. Previous to this state- 
ment, however, Professor Newton concluded that specimens from 
Arctic America sent to him for examination could not be distin- 
guished from true islandicus. The fact that Mr. Dresser has sub- 
sequently (P. Z. iS., 1875, pp. 114-117) insisted on the identity of 
the same specimens with var. gyrfalco , is a somewhat curious cir- 
cumstance, and tends in a measure to confirm the opinion which I 
expressed of the intermediate character of the birds in question. 
