114 BULLETIN 17 9, UNITED STATES NATIONAL MUSEUM 



After the young had left the nest, Mr. Mousley (1934) discovered 

 them, with their parents, "about three hundred yards to the north 

 of the nest. They were in a tangle of small birch-trees, willows, 

 and other shrubs, the intervening spaces being covered with brush- 

 wood and very long grass, making it impossible to get about in a 

 hurry, but forming a wonderful get-away for young birds." Dr. 

 Thomas S. Roberts (1932) says: "After the young leave the nest the 

 entire family keeps together for some time and goes roving about 

 in the upper reaches of the forest, the young, which closely resemble 

 their parents, being fed in part by the old birds while learning to 

 care for themselves. They are all for the most part silent at this 

 time, only an occasional, long-drawn wheep from the adults and 

 weaker calls from the young announcing their presence." 



Plumages. — The young are hatched naked and blind, but they soon 

 become scantily clothed in grayish natal down, which adheres to 

 the tips of the juvenal feathers and does not entirely wear away 

 until the young birds leave the nest. The pattern of the juvenal 

 plumage is essentially like that of the adult, but the colors are some- 

 what duller, the upper tail coverts are "cinnamon-rufous," the outer 

 webs of the tail feathers are edged with rusty, or "cinnamon-buff," 

 the median and greater wing coverts are broadly tipped with "cin- 

 namon-rufous," the buffy edgings of the primaries are broader than 

 in the adult, and the tertials are edged with pale buff. The sexes 

 are alike in all plumages, though the colors of the adult female may 

 be slightly duller. 



Dr. Dwight (1900) says that the first winter plumage is "acquired 

 by a partial post juvenal moult beginning by the middle of August, 

 which involves the body plumage, wing-coverts and tertiaries (ap- 

 parently), but not the rest of the wings nor the tail, young birds 

 becoming practically indistinguishable from adults." This plumage 

 is apparently fully acquired before the birds migrate, but just 

 when the juvenal remiges and rectrices are molted does not seem to 

 be known. Dickey and van Rossem (1938) say: "The only immature 

 bird collected (April 18) has retained its juvenal remiges and rec- 

 trices from the previous year. It is renewing the 7th primary in 

 each wing, in addition to an extensive renewal of the contour plumage. 

 The retention in this single specimen of the juvenal wing and tail 

 feathers is probably an abnormality, for the other species of Myi- 

 archus which occur locally change these at the postjuvenal molt." 



Dr. Dwight (1900) states that the first nuptial and the adult nup- 

 tial plumages are acquired by wear, but I suspect that we may find 

 evidence of a partial prenuptial molt at both ages when sufficient ma- 

 terial is available. Adults have a complete postnuptial molt begin- 

 ning early in August and completed before the birds go south. 



