BIEDS. 55 



They show considerable curiosity upon tlie appearance' of an intruder, and very frequently fol- 

 low one for some distance, uttering a sharp, querulous " kwew," " kwew." When one or more are 

 shot the others circle about a few times, but show very little solicitude over the fate of their com- 

 panions. 



All the examples shot by me in May were extremely handsome, the soft, white plumage being 

 shaded with a delicate rose color. Adult birds taken at Saint Michaels the last of August had a 

 silver gray iris mottled with lavender; bill yellow at tip and dingy yellow at base; feet dingy 

 olive greenish or yellowish. The young of the year at the same season have a hazel iris, dark 

 horn-colored bill, dull flesh-colored at the base, and pale flesh-colored feet and legs. Upon their 

 first arrival in the north these birds seek the vicinity of their summer resorts and are found in 

 the same vicinity until the young are able to fly. 



They nest, like the G-laucous Gull, upon small islets in ponds and lakes. 



Along the coast of Bering Sea they feed upon sticklebacks and other small fry which abound 

 in the sluggish streams and lakes. A bulky nest is prepared of grasses and moss early in June, 

 in which two or three eggs are laid. 



From the 18th to 25th of July most of the young are able to fly, and early in August old and 

 young gather along the courses of streams or near the larger lakes. From this time on many of 

 the birds are found also about low spits and mud flats along the coast. 



The young frequently follow boats for long distances on a stream or near shore, and they are 

 so unsuspicious that they may almost be knocked down with a paddle. 



The old birds pass through the fall moult the latter half of August, and by the middle of 

 September they are in the new dress, and gradually disappear from the north until by the end of 

 this month they become rare. 



In September they fraternize more commonly with the Kittiwakes than at any other season, in 

 the bays and along the coast. 



Larus PHILADELPHIA (Ord). Bonaparte's Gull (Esk. A-tUiig-at). 



On the coast of Bering Sea this is one of the rarest of the gulls. At the Yukon mouth on June 

 4 a single specimen in the immature plumage was secured while feeding in some shallow ponds in 

 company with numerous Sabine's Gulls and Arctic Terns. This was the only spring bird seen by 

 me in the north, and being in the winter plumage was probably a barren bird straying beyond 

 the usual range at this season. 



On September 19 and 20, 1879, 1 found them numerous in flocks along the tide-channels near 

 Saint Michaels. They were hovering in parties with many Short-billed Gulls close to the surface 

 of the water and feeding upon the schools of sticklebacks. They were only seen once again near 

 the locality named and that was at about the same date the succeeding fall. 



Near Sitka specimens were taken by Bischoff, and my native collectors brought me specimens 

 from the vicinity of Nulato, and reported it as occurring about the lakes near the head of Kotzebue 

 Sound. 



Dall found it rather common on the marshes along the Yukon, and notes that they are nu- 

 merous and breed on the Kaiyuh Eiver near Nulato. Eggs have been taken near Fort Yukon. 



Ehodostethia rosea (Macgil.). Eoss's Gull. 



It is with great pleasure that I add this rare and elegant species to our west-coast fauna. 

 The only specimen secured by me, and the only one seen, was a young bird of the year in its first 

 plumage taken near Saint Michaels, Norton Sound, on October 10, 1879. The Eskimo to whom I 

 showed the bird always insisted that it was a young Sabine's Gull, and could not give me the 

 slightest information concerning its occurrence, although it may be more or less frequent near 

 Bering Straits. This specimen measured in the flesh 12.5 inches in total length by 29 inches in 

 extent of wings: Wing, 9.5 inches to carpal joint ; tail, 4 inches ; bill, .6 inch along culmen. The 

 tail contained ten feathers and was cuneate. Bill, black; iris, hazel; feet and legs dull fleshy 

 purple. 



