Back transversely spotted or barred with white. Hab. Hudson’s Bay region; south in winter to northern border of Eastern United States … var. americanus.
Back longitudinally striped with white at all seasons. Hab. Rocky Mountains; north to Alaska … var. dorsalis.
THE BLACK-BACKED THREE-TOED WOODPECKER.
Picus (Apternus) arcticus, Sw. F. Bor. Am. II, 1831, 313. Apternus arcticus, Bp. List, 1838.—Ib. Consp. 1850, 139.—Newberry, Zoöl. Cal. and Oreg. Route, 91, Rep. P. R. R. Surv. VI, 1857. Picus arcticus, Aud. Syn. 1839, 182.—Ib. Birds Amer. VI, 1842, 266, pl. cclxviii.—Nuttall, Man. I, (2d ed.,) 1840, 691.—Sundevall, Consp. I, 1866, 15. Picus tridactylus, Bon. Am. Orn. II, 1828, 14, pl. xiv, f. 2.—Aud. Orn. Biog. II, 1834, 198, pl. cxxxii. Tridactylia arctica, Cab. & Hein. Picoides arcticus, Gray, Gen.—Baird, Birds N. Am. 1858, 98.—Lord, Pr. R. Art. Inst. Woolwich, IV, 1864, 112 (Cascade Mountains).—Cooper, Pr. Cal. Ac. Sc. 1868 (Lake Tahoe and Sierra Nevada).—Samuels, 94.—Cooper, Orn. Cal. 1, 1870, 384.
Picoides arcticus.
Sp. Char. Above entirely uniform glossy bluish-black; a square patch on the middle of the crown saffron-yellow, and a few white spots on the outer edges of both webs of the primary and secondary quills. Beneath white, on the sides of whole body, axillars, and inner wing-coverts banded transversely with black. Crissum white, with a few spots anteriorly. A narrow concealed white line from the eye a short distance backwards, and a white stripe from the extreme forehead (meeting anteriorly) under the eye, and down the sides of the neck, bordered below by a narrow stripe of black. Bristly feathers of the base of the bill brown; sometimes a few gray intermixed. Exposed portion of two outer tail-feathers (first and second) white; the third obliquely white at end, tipped with black. Sometimes these feathers with a narrow black tip.
Hab. Northern North America; south to northern borders of United States in winter. Massachusetts (Maynard, B. E. Mass., 1870, 129). Sierra Nevada, south to 39°. Lake Tahoe (Cooper); Carson City (Ridgway).
This species differs from the other American three-toed Woodpeckers chiefly in having the back entirely black. The white line from the eye is usually almost imperceptible, if not wanting entirely. Specimens vary very little; one from Slave Lake has a longer bill than usual, and the top of head more orange. The size of the vertex patch varies; sometimes the frontal whitish is inappreciable. None of the females before me have any white spots in the black of head, as in that of americanus.