88 BULLETIN 196, UNITED STATES NATIONAL MUSEUM 



Young. — Incubation is apparently performed entirely by the female; 

 I can find no record of the male being seen on the nest; he is, however, 

 always present in the neighborhood and perhaps feeds the female on 

 the nest. Nothing definite seems to be known on the length of the 

 incubation period, which is probably not far from two weeks. 



Dr. Joseph Grinnell (1898) says that, near Sitka, the first young, 

 scarcely feathered, were "taken on July 2. By August 1, the young 

 began to gather in considerable numbers and together with the Rob- 

 ins and other Thrushes were feeding on the blueberries." 



The fact that young have been found in the nests in April and in 

 July would seem to indicate that perhaps, in some cases, two broods 

 are reared in a season. 



Plumages. — A small nestling in my collection, in which the plum- 

 age is just beginning to show in the feathered tracts, is scantily deco- 

 rated on the head and on the alar and dorsal tracts with long "vina- 

 ceous-buff" down, which is fully an inch long on the back. 



The young nestling is scantily covered with grayish down. 



Ridgway (1907) describes the young as "much like the adult female, 

 but under parts more yellowish ochraceous, with feathers of breast 

 and lower throat narrowly margined or tipped with olive or dusky 

 (these markings sometimes indistinct), the jugular band sometimes 

 uniform dull olive, oftener with feathers ochraceous centrally broadly 

 margined with olive and dusky." He says in a footnote: "I am not 

 sure whether the sexes differ or not in first plumage." But seven 

 sexed specimens of young birds indicate "a decided sexual difference, 

 the males having nearly the whole of the lower parts ochraceous and 

 the jugular band indistinct, the females having the posterior half of 

 the lower parts mostly white and the jugular band more or less 

 conspicuous." 



Dwight (1900), however, says that the sexes are indistinguishable 

 in juvenal plumage; they are olive-brown above, plumbeous on the 

 rump, with very faint whitish shaft streaks; "wings and tail clove 

 brown with ochraceous bands edging the quills and tipping the cov- 

 erts. Below ochraceous buff, whiter on abdomen, a pectoral band 

 and edgings of throat and breast, olive-brown. Supra auricular line 

 buff." 



The first winter plumage is acquired by a partial postjuvenal molt, 

 "which involves the body plumage and wing coverts but not the 

 rest of the wings nor the tail, young and old becoming practically 

 indistinguishable." He describes the male in this plumage as "above, 

 deep plumbeous gray with brownish edgings, darker on the pileum, 

 the wing coverts broadly tipped with deep orange buff, forming two 

 wing bands. Below rich orange buff, the abdomen and crissum 

 chiefly white mixed with buff and olive-gray, the sides with olive- 



