BLACK GUILLEMOT. 



387 



rump and patch on the wing are streaked with brown. After the first 

 autumn moult they resemble very closely the winter plumage of adults, 

 except that they retain the wing-coverts of the young in first plumage. 

 After the second autumn moult they are still easily recognized by traces 

 of brown on the white wing-patches, which are not lost until the third 

 autumn moult. Young in down are uniform blackish brown. 



