MNIOTILTIDJE THE AMERICAN WARBLERS 155 



Adult female in spring (No. 83,027, U. 8. Nat. Mug., Mount Carmel. 111., spring; 8. 

 Turner). Similar to the male, as described above, but pileum mixed chestnut and dark 

 umber-brown, distinctly streaked with dusky. Wing.2.35; tail.2.05; bill.from nostril, .28; 

 tarsus, .71. 



A female from Calumet, 111. (No. 83,029, U. S. Nat. Mus., May 12, 

 1875 ; B. W. Nelson), is considerably paler and duller, the lower parts 

 being whitish tinged with yellow on the throat and jugulum, only the 

 crissum continuous yellow ; even the superciliary stripe is white from 

 the eye backward. The pileum is grayish olive, like the back, tinged 

 in one or two places with chestnut, and very indistinctly streaked. 

 The streaks on the sides are almost obsolete, but across the jugulum 

 they are quite well defined. 



Many females, however, are quite as brightly colored as the 

 brightest males, the variation being chiefly individual and not sexual. 



Adult (both sexes) in winter. Lower parts dirty whitish, the breast and sides with 

 narrow streaks of grayish brown; throat and superciliary stripe wholly dirty whitish; 

 yellow entirely con fined to the crissum, except & tinge on the abdomen, and along the 

 edge of the wing in some specimens; crown grayish umber, with but little, if any, tinge 

 of chestnut, and distinctly streaked with dusky. 



This plumage is that of all late fall and winter specimens, whether 

 from far north or the West Indies. I have seen no specimens from 

 the latter region in the spring plumage. 



During the spring migration this is one of the most abundant of 

 the Warblers, and for a brief season may be seen along the fences, 

 or the borders of fields, usually near or on the ground, walking in 

 a graceful, gliding manner, like an Anthvs or Seiurus, the body 

 tilting and the tail oscillating at each step. For this reason it is 

 sometimes, and not inappropriately called Wag-tail Warbler. The 

 species probably does not breed anywhere within the limits of the 

 State, but goes far north to pass the summer. Mr. Kennicott found 

 a nest at Fort Eesolution, in Arctic America. It was on the ground, 

 on a hummock, at the foot of a small spruce tree in a swamp. 

 When discovered (June 18), it contained five young. 



Dendroica discolor (Vieill.) 



PRAIRIE WARBLER. 

 Popular synonym. Chestnut-backed Yellow Warbler. 



Sylvia discolor VIEH.L. Ois. Am. Sept. ii, 1807, 37, pL 98. NUTT. Man. 1,1832, 394 T294" by 



error). A UD. Orn. Biog. i,1831, 76, pi. 14. 



Sylvicola discolor JAKD. AUD. Synop. 1839,62; B. Am. ii, 1841, 68, pi. 97. 

 Dendroica discolor BAIBD, B. N. Am. 1858,290; Cat. N. Am. B. 1859, No. 210; Review, 

 1865,213. B. B. & R. Hist. N. Am. B. i, 1874, 276, pi. 14. fig. 9. 



