532 NORTH AMERICAN BIRDS. 



winter or in March. Two were taken near Salem in November. It is also 

 a rare winter visitant near Hamilton in Canada. 



Mr. Eidgway met with but a single individual of this species during his 

 Western explorations. This was shot in February, near Carson City, Nevada ; 

 it was busily engaged in pecking upon the trunk of a large pine, and was 

 perfectly silent. 



Mr. John K. Lord obtained a single specimen of this bird on the summit 

 of the Cascade Mountains. It was late in September, and getting cold ; the 

 bird was flying restlessly from tree to tree, but not searching for insects. 

 Both when on the wing and when clinging to a tree, it was continually 

 uttering a shrill, plaintive cry. Its favdrite tree is the Pinus contorta, which 

 grows at great altitudes. It is found chiefly on hill-tops, while in the val- 

 leys and lower plains it is replaced by the Picoidcs hii^sutus. 



Eggs of this species were obtained by Professor Agassiz on the northern 

 shore of Lake Superior. They were slightly ovate, nearly spherical, rounded 

 at one end and abruptly pointed at the other, of a crystal whiteness, and 

 measured .91 of an inch in length by .70 in breadth. 



An egg received from Mr. Krieghoff is small in proportion to the size 

 of the bird, nearly spherical in form, and of a uniform dull- white color. It 

 measures .92 of an inch in length by .76 in breadth. 



Picoides tridactylus, var. americanus, Brehm. 



THE WHITE-BACKED THREE-TOED WOODPECKER. 



Picus hirsutus, Vieillot, Ois. Am. Sejit. II, 1807, 68, pi. cxxiv (European specimen). — 

 Wagler, Syst. Av. 1827, No. 27 (mixed with undulatus). — Aud. Orn. Biog. V, 1839, 

 184, pi. ccccxvii. — Ib. Birds Amer. IV, 1842, pi. cclxix. — Nuttall, Man. I, (2ded.,) 

 1840, 622. Aptcrnus hirsutus, BoN. List. Picoides hirsutus, Baird, Birds N. Am. 1858, 

 98. — Samuels, 95. 1 Picus undulatus, Vieillot, Ois. Am. Sept. II, 1807, 69 (based 

 on PI. enl. 553, fictitious sjiecies ?) Picus undatus, Temm. Pic^(,s undosus, Cuv. R. A. 

 1829, 451 (all based on same figure). Tridactylia undulata, Cab. & Hein. Mus. Hein. 

 IV, 2, 1863, 28. Picus tridactylus, Sw. F. Bor. Am. 1831, 311, pi. Ivi. Picoides 

 americanus, Brehm Vogel Deutschlands, 1831, 195. — Malherbe, Mon. Picidse, I, 

 176, pi. xvii, 36. — ScLATER, Catal. — Gray, Cat. Br. Mus. Ill, 3, 4, 1868, 30. Ap- 

 tcrnus americanus, Swainson, Class. II, 1837, 306. Picus americanus, Sundevall, 

 Consp. Av. Picin. 1866, 15. Picoides dorsalis, Baird, Birds N. Am. 1858, 100, pi. 

 Ixxxv, f. 1. — Cooper, Orn. Cal. I, 1870 (under P. americanus). Tridactylia dorsalis. 

 Cab. & Hein. Picus dorsalis, Sundevall, Consp. 1866, 14. 



Sp. Char. Black above. The back markings of white, transverse in summer, and 

 longitudinal in winter ; these extend to the rump, which is sometimes almost Avholly 

 white. A white line from behind the eye, widening on the nape, and a broader one 

 under the eye from the loral region, but not extending on the forehead : occiput and sides 

 of head uniform black. Quills, but not coverts, spotted on both webs with white, seen on 

 inner webs of inner secondaries. Under parts, including crissum, white ; the sides, includ- 

 ing axillars and lining of wing, banded transversely with black. Exposed portion of outer 

 three tail-feathers white ; tliat of third much less, and sometimes with a narrow tip of 

 black. Upper tail-coverts sometimes tipped with white, and occasionally, but very rarely, 



