LIFE HISTOEIES OF NORTH AMERICAN WILD FOWL 253 



brownish shades, such as " cinnamon buff "' or " ochraceous buff " ; 

 some of the eggs seem to be wholly of these darker shades ; in others 

 the stains have apparently worn off or been scratched off, exposing 

 the original color. The shell is smooth and sometimes quite glossy. 



The measurements of 107 eggs in the United States National Mu- 

 seum and the author's collections average 71.1 by 47.4 millimeters; 

 the eggs showing the four extremes measure 79 by 47.5, 68 by 51, 66 

 by 45 and 75,5 by 43.5 millimeters. 



Plumuges. — The downy young black brant is thickly covered with 

 soft down in dark colors ; the upper half of the head, including the 

 lores, to a point a little below the eyes is " fuscous " or " benzo 

 brown " ; the chin is white ; the back varies from " benzo brown " to 

 " hair brown," darkest on the rump ; the flanks and chest shade from 

 " hair brown " to " light drab," fading off nearly to white on the 

 belly and throat. 



I have seen no specimens showing the change from the downy to 

 the Juvenal plumage. But a bird in the juvenal plumage, taken 

 September 5, has the whole head, neck and breast plainly colored, 

 " fuscous " to " fuscous black," with onW faint traces of the white 

 markings on the neck ; the feathers of the back are edged with grayish 

 white or huffy white; the juvenal wing has broad, conspicuous, pure 

 white edgings on the lesser and the greater coverts, the secondaries, 

 and the tertials, broadest on the greater coverts ; the belly and flanks 

 are plain " fuscous," with no barring. 



Molting begins first on the head and neck ; the white neck patches 

 are often, but not always, conspicuous in October; they are well 

 developed by spring. Aside from a partial molt of body and tail 

 feathers there is not much change during the winter and spring. 

 Young birds in May and Jime are still decidedly juvenal, much 

 worn and faded. At the following post-nuptial molt, when a little 

 over a year old, the young bird undergoes a complete molt and be- 

 comes practically adult in plumage, with white neck patches, barred 

 flanks, and plain dark wings without any light edgings. 



Food. — The black brant, like its eastern relative, is a decidedly 

 maritime bird, living on salt water and feeding on the grassy mud 

 flats; it never comes in to the uplands to feed. It seems to feed 

 almost entirely on the leaves and roots of various marine grasses, 

 mainly Zostera. In connection with its vegetable food it picks up 

 various small mollusks, crustaceans, and other forms of marine 

 animals, Mr. W. Leon Dawson (1909) says that they "not only 

 dip but dive as well." 



Behavior. — Doctor Nelson (1881) gives such a good account of 

 the flight of the black brant that I quote it in full, as follows ; 



The flight of this species is peculiar among North American geese and bears 

 a close resemblance to that of the eider and otiier species of heavy-bodied short- 



