182 KATUEAL HISTOEY COLLECTIONS IN ALASKA. 



There is a ^■el.v (iecidcd aiuouut of individual variation among the specimens of this bird in my 

 collection, which is composed mainly of winter birds. This variation appears to be, however, as 

 stated, purely individual, since a comparison between birds of this species from various localities 

 ou the two continents shows no geographical difference. The range of individual variation ap- 

 pears much greater than is shown among the allied species, and I append notes of some of the most 

 remarkable states of plumage. Its fondness for wandering from place to place is exhibited iu the 

 north, as well as south, and iu summer, except during the breeding season, it is found scattered 

 everywheie throughout its northern range. The parents and young wander reistlessly wherever 

 their inclination leads, until, at the approach of winter, they baud together in parties of various 

 sizes and betake themselves to the south. 



One specimen, a female, obtained at Saint Michaels, April, 1879, is pure white over the entire 

 body, with the exception only of the tijis of the primaries for an inch from their ends. This part 

 of the primaries is jet black, m ainly ou the inner web, with a narrow edge of white at the tip, but 

 the shaft and most of the outer web are white. The tail is pure white without a trace of black. 

 The bases of the feathers are not black, as is usually the case with this bird, but are dark sooty- 

 plumbeous. Feet black, bill pale. This biid is not an albino, as is shown by the black wing lips, 

 which have much the same color arrangement as is exhibited in the gulls. Another specimen 

 somewhat similar has the tips of the two middle tail-feathers black and black-shaft lines ou the tips 

 of the other tail-feathers. It has also black wing-tips and black tips to the tertials with the bases 

 of these feathers white. The crown and back are washed with rusty. This bird was taken at 

 Uoalaska Island in January.* The third curious plumage shown in a bird taken at Saint Michaels 

 in February, 1S79, has the four outer tail-feathers white, with the other half of the shaft black. 

 The central tail-feathers are very dark brown, edged with white, with the basal parts of webs, 

 excepting the two middle feathers, white. The wings are dark brown and colored much as usual, 

 but the dark bases of the feathers on the back terminate in long narrow pointed slmft-liues edged 

 with dull, yellowish white, which gives the back a striated appearance of brownish lines and 

 yellowish-white interspaces. 



A female taken at Saint Michaels August 2i, 1S79, is in full winter dress, and a fine series 

 from Fort Eeliance, on the Upper Yukon, taken early iu April, shows conclusively that this bird 

 does not pass through a spring moult, but that the rusty edges or tips of feathers wear away and 

 leave exposed the beautifully contrasted black and white characteristic of the breeding birds. 



The female — parent of the egg described from Saint Lawrence Island — though much worn, 

 has the feathers still edged with dingy yellowish on the head and grayish-white on the back, 

 and thus appears much duller than the summer male. The rapid wearing away of the feathers 

 in spring is similar to the process undergone by the fur-bearing mammals at that season— the rays 

 of the sun, with the fierce reflection from the snow, bleaches the dark color of the winter fur to a 

 much lighter shade, and renders the ends of the hair so brittle and harsh that by the last of March 

 and first of April the skins of the foxes and other fur-bearing animals are worthless. Animals 

 killed at this season show that the hair becomes shorter and shorter, by abrasion, as the season 

 advances. Compared with the fine, glossy fur of winter, the difference is very striking, and would 

 seem to show that shedding had taken place were we not aware of the actual cause. 



It is to be supposed that the featheis of birds, when the breeding season approaches, receive 

 additional coloring matter which vivify the tints of the plumage, as is best exemplified in tbe 

 gulls, which are rose-tinted iu spring. 



Plectrophenax hyperbokeus Ridgw. McKay's Snowflake. 



This species was described iu Proceedings U. S. National Museum, vii, June 11, 1884, p. G8, 

 from specimens taken by Mr. Nelson at Saint Michaels, and by Mr. McKay at Nushagak, Bristol 

 Bay. At both localities the bird appears to be a migrant only. Eecently Mr. Townseud has found 

 the bird breeding in abundance on Hall Island, Bering Sea, and the species is likely to prove an 

 insular form, with its breeding-ground restricted to this and perhaps the neighboring islands of Saint 



* The specimens here alludecl to by Mr. Nelson, v, ith otliers taken liy McKny at Xnshagali, were siibseqneutly 

 described by Mr. Eidgway as the P. hyperhoreus. 



