THE ARCTIC THREE-TOED WOODPECKER. 267 



completed, its usual depth being from twenty to twenty-four inches. It is 

 smooth and broad at the bottom, although so narrow at its entrance as to 

 appear scarcely sufficient to enable one of the birds to enter it. The eggs 

 are from four to six, rather rounded, and pure white. Only one brood is 

 raised in the season. The young follow their parents until autumn, when 

 they separate and shift for themselves. They do not attain their full 

 plumage until the second year. 



The number of these Woodpeckers is greatly increased in the State of 

 Maine during winter, by accessions from Nova Scotia, Newfoundland, and 

 Labrador, in all which countries I have found the species in summer, but 

 where, if I am rightly informed, few remain during severe winters. 



Picus tridactylus, Bonap. Syn., p. 46. 



Northern Three-toed Woodpecker, Picus tridactylus, Bonap. Amer. Orn., vol. ii. 



p. 14. 

 Picus (apternds) arcticus, Arctic Three-toed Woodpecker, Swains, and Rich. F. 



Bor. Amer., vol. ii. p. 313. 

 Northern Three-toed Woodpecker. Nutt. Man., vol. i. p. 578. 

 Three-toed Woodpecker, Picus tridactylus, Aud. Orn. Biog., vol. ii. p. 198. 



Male, 101, 16. 



From the northern parts of New York to the Fur Countries, as well as 

 along the eastern declivities of the Rocky Mountains. Rather common. 

 Partially migratory. 



Adult Male. 



Bill longish, straight, strong, angular, compressed toward the tip, which 

 is slightly truncate and cuneate; upper mandible with the dorsal line straight, 

 the ridge distinct, the sloping sides quite flat, the lateral angle or ridge close 

 to the edges, which are acute and overlapping; lower mandible with the 

 ridge distinct, the sides convex, edges sharp and inflected. Tongue com- 

 paratively shorter than that of the Picus villosus, but of the same form, the 

 extensile part being vermiform, the tip flat above, convex below, and 

 serrated backwards on the thin edges. Nostrils basal, elliptical, covered by 

 the feathers. Head rather large, neck short, body robust. Feet very short; 

 tarsus scutellate before and behind; two toes before, one only behind, which 

 is versatile and larger, all scutellate above; claws strong, extremely com- 

 pressed, very acute, and uncinate. 



Plumage blended, glossy, on the back and wings rather compact. Feathers 

 of the top of the head stiff and silky. Wings longish, third and fourth 

 quills longest and equal. Tail graduated, of twelve decurved stiff feathers, 

 worn to a point, excepting the outermost, which is extremely small. Base 

 of the bill covered by recumbent bristly feathers. 



