36 Dwight, The White-winged Gulls. [j" n k 



maried species. They fade to a decidedly brown shade, almost 

 mouse gray, but their color (especially that of the primaries) and 

 the size of their bills even when young are cardinal points by 

 which to recognize them. 



The first winter plumage is like the juvenal, but at the pre- 

 nuptial moult white about the head and body and gray on the 

 back begins to appear in some specimens, thus marking the first 

 nuptial plumage. 



In the second winter plumage unpatterned drab or mouse-gray 

 primaries are most frequent, together with the gray mantle of the 

 adult. The white head and neck, as in the other species, are 

 much clouded with dusky markings, which are lost at the next pre- 

 nuptial moult. I do not think that primaries with the apical 

 white spots of the adult bird are ever developed until a year later, 

 but in some birds there is a foreshadowing of the white spot on 

 the first primary. The third winter plumage, that of the adult, 

 is the result of the second postnuptial moult, after which very few- 

 birds can be found showing traces of immaturity. The new pri- 

 maries are slaty, and white-tipped, the first and sometimes the 

 second with subapical or sometimes terminal white 'mirrors,' 

 quite unlike the unpatterned feathers of glaucus or the smaller 

 leucopterus. The mantle varies from cinereous to plumbeous 

 gray, the color running over into the primaries, which become 

 decidedly slaty towards their apices. The white of the head 

 and neck is still clouded, the dusky markings being characteristic 

 of winter plumages until the birds are quite advanced in age. 

 At prenuptial moults, as in the other species, these feathers are 

 replaced by white ones. 



Larus kumlieni. Kumlien's Gull. 



Since this species was described in 1883 by Mr. Wm. Brewster 

 nothing has been added to our knowledge of it save the recording 

 of additional specimens. I have examined twenty-two of these 

 birds, about a dozen in adult plumage, several in intermediate 

 immature stages, and four in a plumage that I am convinced is 

 the undescribed plumage of the young bird. This material shows 



