CRUISE OF STEAIMER COR WIN IN THE ARCTIC OCEAN. 81 



perliiips, of tlic easteruiiiost island adjoining- tiie peiiinNula of Aiia.ska, where two species of 

 Ptarmigan are -said to occur. To the west of the island on the Aleutian chain it is not found, 

 being replaced by the species mentioned below. Neither is it found on the fur seal nor any of the 

 other islands in Beiing Sea, with the possible exception of Saint Lawrence. In the autumn, just 

 previously to the severe winter storms, there is a jtartial migration of this Ptarmigan from 

 the Arctic coast south to the valleys of the Yukon and Kusko(iuim, whcsre the sheltering thickets 

 of willow and alder aft'ord it refuge during tlu; winter. x\s spring re-opens it passes to the 

 north and regains its breeding grounds. Some of the hardier among these birds, however, remain 

 during the entire winter in the extreme north. On Septembers, 1881, while the (Jorwin lay in 

 Kotzebue Sound, tli(;se Grouse were gathering in considerable flocks, j)reparitig for their southern 

 migration. They were found along the shore where the abunilant supply of berries afforded them 

 food. They were attended as usual by numerous Goshawks, and sevei'al Gyrfalcons were seen in 

 the vicinity. In spring, while the males are paying court to the objects of their choice, they select 

 some slight elevation, such as a prominent knoll or a snow bank, upon which they take their stand 

 and utter their loud, harsh note of defiance, or do battle with some roving free-laiu'C of their kind. 



LAGOPUS RUSPESTRIS (Gm.) Leach. 



(78.) The Rock Ptarmigan. 



Along the eastern shore of Bering Sea and the Arctic Ocean in Alaska, wherever the mount 

 ains or higli hills approach the sea, this grouse occurs. It is found in the immediate vicinity of 

 Saint Michael's, frequenting the hill-tops in summer and seeking the shelter of the willows and 

 alders about their bases in winter. On the coast to the north, reaching the vicinity of Bering 

 Strait, I found them numerous in the winter of 1879. They are much more unsuspicious than the 

 preceding species, and will allow a very close approach, standing with their heads raised inquir- 

 ingly and a pretty air of wonderment about them. In winter their beautiful milk-white plumage, 

 with the sharply contrasted jet-black bill and bar through the eye, renders them very hand- 

 some objects, particularly when seen in life. Their shape and moveiueuts on the grountl are also 

 much more graceful and elegant than those of the ordinarj^ Pt.armigan. They exist in far smaller 

 numbers than the White Ptarmigan, and their range is more restricted, owing to the low and little 

 varied character of the northern coast country. Wherever low mountains or hills occur throughout 

 the iu>rthern portion of the territory, however, this bird may be confidently expected to occur. On 

 the Aleutian Islands it is rein-esenfedby forms which are mentioned below, and the Siberian shore 

 has a form perhaps identical with this; but, as Professor Nordenskiold records those taken by the 

 Vega party at their winter quarters as L. siibalpinus, this name is accepted as applying to the North- 

 ea.stern Siberian bird, since there are no specimens at liand from that region. 



LAGOPUS RUPESTRIS (Gm.) Leach. , 



(79.) Rock Ptarmigan. 



On the Island of Ounalaska, thence to the eastward and also to the westward for an uncertain 

 distance, occurs the handsome Ptarmigan designated above. Of this form there are but two 

 specimens in existence in the summer plumage. These are a male and female obtained by me on 

 the hills back of Ounalaska in the spring of 1877. The winter bird, of which the Smithsonian 

 possesses a single exami)le obtained by Mr. Dall, is indistinguishable from the winter plumage of 

 the ordinary Rock Grouse. This specimen lacks the black border through the eye, but this 

 character appears to be merely individual. This is the species which in Mr. Dall's papers on the 

 birds of the Aleutian Islands he designated as the White Ptarmigan, Lat/opus albus, and in 

 the Bulletin of the Nuttall Ornithological Club for 187 I recorded the capture of the two 



specimens previously mentioned under the name oi Lagopus riq)e.stris. 



Beyond the more ca[)ture of the bird there is little known of its habits, the only data which I 

 can furnish being that it frequents the mountain tops and slopes among the Eastern Aleutian 

 Islands, and is common there, breeding during June. 



The detailed description of this form will be given in the account of the Birds of Ala.^ka, now 

 in course of preparation. 

 H. Ex. 10,5 11 



