1498 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 3 



most part in their sheaths, and the tertials so short that their rich edgings are 

 not yet apparent. The streaking of the chest is quite sharp, but on the sides it is, 

 if anything, less marked than in later stages. Male and female birds are appar- 

 ently not distinguishable at this age. The pectoral streaking is so much intensified 

 because the feathers lie close together and are partially sheathed, that the actual 

 width of the streaks is difficult to determine. 



By the time the tail is an inch long the feathers of the face are almost altogether 

 unsheathed, the tertials and secondaries are practically of full length, the pectoral 

 plumage is fully fluffed out, and the bird is, therefore, much more colorful in ap- 

 pearance. At this stage males may, with a fair degree of certainty, be distin- 

 guished from females by the heavy streaking of the chest. Chapman * * * tells 

 us that the "breast blotch is wanting" in this plumage. While this is no doubt to a 

 considerable extent true, two individuals in a series of eleven specimens at hand 

 show a definite blotch and two others exhibit a tendency toward convergence of 

 streaks in the middle of the chest. 



Sutton considers that song sparrows have a rather definite and com- 

 plete juvenal plumage. "By the time the juvenal rectrices are of 

 full length the body plumage is comparatively complete with all the 

 feathers unsheathed and with no noticeable intrusion of pin-feathers 

 of some subsequent plumage." He says that "specimens in juvenal 

 feather may be taken during a long period of the summer," but is 

 cautious about concluding how long the individual bird wears the 

 plumage. 



The foregoing is essentially an account of the molt, not the plumage, 

 of which Dwight (1900) gives a good description. The bird "resembles 

 Z. albicollis, but lacks chestnut above" and is "paler on [the] crown 

 and less streaked below. Above, including sides of head, wood-brown 

 or sepia broadly striped on back, narrowly on crown, nape and rump 

 with dull black, the feathers centrally black with a narrow zone of 

 walnut and wood-brown and grayish edgings. Indistinct median 

 crown and superciliary stripes dull olive-gray with dusky shaft 

 streaks. Rictal and submalar streaks black ; orbital ring buff. Wings 

 dull black with walnut edgings, the wing coverts and tertiaries buff 

 tipped. Tail olive-brown broadly edged with walnut and indistinctly 

 barred. Below, dull white washed with pale or yellowish buff deepest 

 on the throat and flanks and streaked on sides of chin, throat, breast 

 and sides with dull black. Feet and bill pinkish flesh, becoming dusky 

 with age, the lower mandible remaining partly flesh-color." Dwight 

 believes this plumage is worn several months; it fades considerably. 



The first winter plumage is acquired, according to Dwight, "by a 

 partial, sometimes complete, postjuvenal moult" beginning in some 

 birds in mid-August, in others not until the last of September. These 

 latter will still show new feather growth late in October or early in 

 November, although "the whole period of moult does not cover 

 much more than two months in the majority of cases." The molt 

 "involves the body plumage and the tail and very often, part at least, 



