Notes on the Plumage of the North American Sparrows 17 



the adult. The spring fcathcr-gnnvth is cunfincd U> the chin, and the breeding 

 birds differ from winter ones in being somewhat grayer, in the absence of margins 

 to the feathers of the crown and their reduction on the feathers of the back, 

 giving to the last-named area a more sharply streaked appearance. 



Tlie Western Tree Sparrow differs from the eastern race chiefly in being paler 

 above. 



Field Sparrow (Dec, Fig. 4). The Field Sparrow needs comparison with 

 no otiier s])ecies, its general reddish brown color and pinkish bill easily distin- 

 guishing it. The sexes are alike, and there are no marked seasonal changes in 

 plumage. The nestling is streaked below, but in the fall the young bird resembles 

 the adult, and both differ from summer specimens in being richer in tone and 

 in having a darker suffusion of buff' on the breast and sides. The spring molt 

 appears to be restricted to the chin, and the iDreeding plumage is acquired by wear 

 and fading. 



The Western Field Sparrow is a strongly marked race which is much paler 

 than the eastern form, the general tone of the color above being no browner than 

 in the Clay-colored Sparrow. 



Clay-colored Sparrow (Dec, Fig. 5). The Clay-colored and Brewer's 

 Sparrows closely resemble one another and at times are distinguished with 

 diiSculty. In breeding plumage the former is somewhat browner above, with 

 the black streaks decidedly broader; the hind-neck is grayer; the median crown 

 stripe and superciliary line more pronounced, and there is a more or less sharply 

 defined ear-patch. I have, however, seen fall and winter specimens in which 

 these characters were less pronounced, and which so closely approached some 

 specimens of Brewer's Sparrow that it was questionable to which species they 

 belonged. 



The Clay-colored Sparrow shows no variation with sex, and, as a rule, but 

 little with age or season. Adults, in fall, resemble the young, and at this season the 

 plumage averages browner than in summer; this affects the sides of the head and 

 breast, and the supercihary line is not so well marked, the crown stripe less 

 detined, and the gray hind-neck band is not evident. The spring molt, so far as 

 I have observed, occurs in April and involves the chin, crown, wing-coverts and 

 tertials; and the renewal of feathers in these parts, with some fading of the feathers 

 which are not molted, brings the bird into breeding plumage. 



Brewer's Sparrow (Dec, Fig. 6). This species may be known from its 

 nearest relative, the Clay-colored Sparrow, by the characters mentioned under 

 that species, with which it agrees in varying but little with age or season. Fall 

 specimens are more buffy than those in summer plumage, and the young of the 

 year, at this season, have the wing-coverts tipped with buff. The nestling is streaked 

 below, and in this plumage is difficult to distinguish from the nestling of the 

 Western Chipping Sparrow. 



The spring molt appears to be confined to the head, where there is a slight 

 feather-growth, and one April specimen has been examined which is acquiring 



