74 BULLETIN 17 0, UNITED STATES NATIONAL MUSEUM 



above and nearly pure white and longer down below. In a young bird, 

 18 days old and nearly fully grown, the primaries have begun to burst 

 their sheaths and are about 1 inch long; the tail feathers are in about 

 the same condition, but are only about three quarters of an inch long ; 

 the head and body are still wholly downy, except that feathers are 

 appearing on the scapular region. 



In fresh juvenal plumage, the crown is "russet", broadly streaked 

 with black; the mantle is "bone brown" to "clove brown", with narrow 

 "russet" edgings, and with a purplish sheen; there are some tips and 

 concealed spots of "orange-cinnamon" on the scapulars and remiges; 

 the tail is black, or slightly brownish, with narrower gray bars than in 

 the adult, and broadly tipped with "pinkish buff"; the under parts 

 are "cinnamon" to "cinnamon-buff", broadly streaked, except on the 

 chin and throat, with "sepia" or "bister." 



The sexes are alike in this plumage, which closely resembles that of 

 the adult female. This plumage is worn for nearly a year with no 

 change, except by wear and fading. By late in winter or early in 

 spring the upper parts have faded out to "olive-brown", "buffy 

 brown", or even "drab"; and the under parts are white, or creamy 

 white, streaked with "snuff brown", or even paler browns. 



In April or May, when the bird is less than a year old, the molt into 

 the adult plumage begins; the body plumage is molted first and the 

 wings and tail later. I have seen molt in the wings in June, but usu- 

 ally it does not begin until July. The complete molt may not be 

 finished until November. 



In adult plumage the sexes are quite different. In the male the 

 upper parts are "plumbeous", darkest on the upper back; the tail is 

 mainly black, tipped with grayish white, and with broad "cinereous" 

 bands; the streaks on the under parts are black, or nearly so. The 

 female is brown above, uniform "warm sepia" to "bister"; the tail is 

 "olive-brown" to "clove brown", with narrower, pale buffy bars; and 

 the streaks on the under parts are "sepia." 



The annual, complete molts of adults are irregular and prolonged, 

 much as in the young birds. Witherby's Handbook (1924) says, of 

 the European merlin, that the complete molt begins with the wing 

 feathers in June and is completed usually in November, but some- 

 times not until December or even January. It also says that "what 

 certainly appears to be a second moult confined to body feathers takes 

 place Feb. -March and occasionally not finishing until April." It 

 seems to me that this merely shows that the body molt precedes the 

 wing molt. I once collected a breeding pair of pigeon hawks on June 

 17; the male was in fully adult plumage, but the female was mainly 

 in immature plumage, much worn, and was molting the body plumage 

 and the wings. This shows that sometimes at least these falcons, like 



