SURF BIRD 273 



are apparent on this egg. Egg number tbree is similar both in ground color 

 and iu markings to egg number two, except in egg number three the heavy 

 bay markings form a decided wreath 21 millimeters in diameter about its 

 larger end. Egg number four has the richest ground color of all, w^hile its 

 markings are fawn, but the markings are not so sharply defined as in the 

 other eggs. 



The four eggs measure 43.7 by 30.5, 41.5 by 31.5, 43.3 by 31.2, and 

 42.4 by 31, and they average 42.7 by 31 millimeters. 



Young. — Mr. Dixon (1927) demonstrated most conclusively that 

 the male does most, if not all, of the incubating. The bird that 

 they had under observation for 16 hours and the only one seen near 

 the nest proved to be the male. All of the five males collected had 

 bare incubation patches, while none of the females had these. Mr. 

 Murie (1924) found both parents attending the young bird which 

 he captured; and the one shot, probably the more solicitous one, 

 was the male. Evidence is accumulating all the time to show that 

 with more shore birds than we realize, perhaps with all, the males 

 perform the greater part of the domestic duties. 



Plmnages. — The young bird taken by Mr. Murie is still in the 

 downy stage. The upper parts are variegated and mottled with 

 "cinnamon buff," brownish black, " sepia," and buffy white ; the 

 forehead and sides of the head are buffy white, boldly spotted and 

 striped with black; the crown is mainly spotted with black; the 

 buffy tints are mainly on the upper back, wings, thighs, and rump ; 

 the under parts are grayish white, whitest on the chin and belly. 



When the young birds come down to the coast of Alaska, in 

 August, they are in full juvenal plumage. In this the crown is 

 streaked with " fuscous " and brownish black, the feathers having 

 white edgings; the chin and throat are white, with shaft streaks of 

 " hair brown " ; there is a broad band of " hair brown " across the 

 breast, with white edgings, running into spots below, which are 

 lacking on the white belly ; the mantle is " hair brown," with very 

 narrow whitish edgings, giving a scaled appearance; the scapulars 

 also have a subterminal " fuscous " bar ; the lesser and median wing 

 coverts are broadly or conspicuously edged with grayish white. 



A partial post juvenal molt in the early fall produces a first winter 

 plumage which is like the adult winter, except that there are fewer 

 and smaller spots on the under parts; and the juvenal wing coverts 

 and some scapulars are retained. 



Two specimens, collected in Peru on June 30, illustrate the first 

 nuptial plumage. These are doubtless birds which do not migrate 

 north to breed during their first year. Apparently a nearly com- 

 plete molt has taken place, as the wings and tail appear fresh, but 

 some of the old scapulars and wing coverts are retained. The adult 

 nuptial plumage is suggested, but aU traces of cinnamon are lacking ; 



