In Western Massachusetts it is a very abundant spring and autumn visitant, making but a brief stay in spring, but passing northward in large numbers. In autumn it remains longer, and passes south more leisurely. Mr. B. P. Mann found its nest and eggs in Concord, but this was probably an exceptional instance. In Eastern Maine it arrives May 25, and, as Mr. Boardman thinks, remains to breed. Both Dr. Suckley and Dr. Cooper met with this species in Washington Territory, where it is very rare. No writers have observed or noted the song of this bird, except Mr. T. M. Trippe (American Nat., II. p. 171), who states that during its spring migrations it has a very sweet song or warble, uttered at short intervals. It reaches the high northern latitudes late in May, and leaves that region in September. The observations of Mr. McFarlane show that the nests of this bird are moderately common at Anderson River, and are generally built in low spruce-trees four or five feet from the ground. In one or two instances it was placed on the ground. The eggs of this Warbler vary from .72 to .80 of an inch in length, and from .50 to .55 in breadth. Their ground-color is white, often tinged with a bluish shade, and blotched and spotted with reddish-brown, purple, and darker shades of brown. They are of a rounded oval shape. Dendroica auduboni, BAIRD. AUDUBON’S WARBLER; WESTERN YELLOW-RUMP. _Sylvia auduboni_, TOWNSEND, J. A. N. Sc. VII, II, 1837.—IB. Narrative, 1839, 342.—AUD. Orn. Biog. V, 1839, 52, pl. cccxcv. _Sylvicola auduboni_, BON. List. 1838.—AUD. Birds Am. II, 1841, 26, pl. lxxvii. _Dendroica auduboni_, BAIRD, Birds N. Am. 1858, 273; Rev. 188.—SCLATER, P. Z. S. 1858, 298 (Oaxaca; October); 1860, 250 (Orizaba).—SCLATER & SALVIN, Ibis, 1860, 273 (San Geronimo, Guat.).—COOPER & SUCKLEY, P. R. R. Rep. XII, II, 1859, 181.—SCLATER, P. Z. S. 1864, 172 (City of Mexico).—COOPER, Orn. Cal. 1, 1870, 88. SP. CHAR. Above bluish-ash, streaked with black, most marked on the middle of the back; on the head and neck bluish-ash. Middle of crown, rump, chin, and throat, and a patch on the side of the breast, gamboge-yellow; space beneath and anterior to the eyes, forepart of breast and sides, black; this color extending behind on the sides in streaks. Middle of belly, under tail-coverts, a portion of upper and lower eyelids, and a broad band on the wings, with a spot on each of the four or five exterior tail-feathers, white; rest of tail-feathers black. _Female_ brown above; the other markings less conspicuous and less black. Length, 5.25; wings, 3.20; tail, 2.25. _Young_, first plumage, whole body, including head all round and rump, conspicuously streaked with slaty-black upon an ashy ground above and white below. No yellow on crown, rump, breast, or throat. Wings and tail as in autumnal adult.