12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 66 



about one-fourth the size of adults, but a few eggs were noted. The 

 nests were inaccessible, but looking over the edge of the cliff from 

 the top of the island I could see the contents of about lOO nests below 

 me. At East Cape young were still in the nests on August 29, but 

 young on the wing were also seen about this date. 



LARUS HYPERBOREUS 



Glaucous Gull 



The dominant bird of Bering Sea. They were abundant every- 

 where north of the Seal Islands. They followed the ship as we 

 cruised along the coast and bedded in the water all around us when 

 we anchored. 



Where so many were gathered together, great variations were 

 noted in their plumages. Four very distinct types were represented. 

 First, and perhaps most abundant, was a quite dark mottled bird with 

 blackish primaries and a bill mostly dusky. These were birds of the 

 previous year and were from 10 to 12 months old. The second 

 stage was a much lighter, brownish or ecru-colored bird apparently 

 barred rather than mottled, with light primaries, sometimes nearly 

 white, and a dark bill. This form was more common in August and 

 early September, at which time many birds intermediate between 

 this and the first stage were noted. I believe this is the second winter 

 plumage, the intermediate specimens seen being probably moulting 

 birds. Earlier in the season (June and July) a comparatively small 

 number similarly colored were seen, which may have been precocious 

 individuals of about one year, or fully as likely backward birds of 

 the second summer which still retained the plumage of the previous 

 winter. Some birds in this plumage also had gray feathers in the 

 back. The third and rarest was the white hutchinsti type. This 

 phase was only seen in early summer and seldom were birds pure 

 white. Usually they had a small amount of gray in the mantle. A 

 bird of this kind was shot June 29. I doubt if this plumage is 

 regularly assumed by any very large proportion of the species. I 

 am inclined to think that it is produced by birds lacking in vitality or 

 otherwise unable to take on the complete adult plumage at one moult. 

 They may be birds that have started to acquire the adult plumage 

 earlier than usual but lack the necessary pigment to produce it entire. 

 I think it represents birds 22 to 24 months old in the seeond nuptial 

 plumage, but normally the second nuptial plumage appears to be the 

 light ecru-drab second stage plus a greater or less proportion of 

 gray feathers in the mantle. The fourth type of plumage was the 



