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others in June. Those obtained in May had changed considerably 

 toward the summer dress, while those taken in June were in complete 

 breeding plumage. On May 24 I spent the day on Atka Island, and se- 

 cured a dozen good specimens of Turner's Ptarmigan. They were usually 

 found low down, either in the lowest heather or among the tall dead 

 grass of the lowest hills. They were always seen in pairs, and were 

 evidently mated. When flushed the male utters a coarse, gutteral note, 

 not distinguishable by me from that of Nelson's. Most of their crops 

 were empty, but some were filled with leaves of Empetrum nigrum. While 

 the higher parts of the island were still covered with snow, the portions 

 where we found the ptarmigan w r ere almost wholly free of snow, and 

 these birds were, as might be expected, in almost complete summer 

 plumage. 



The various species of ptarmigan are, as you know, non-migratory, in 

 this respect resembling our native quail of Indiana; and the individuals 

 found upon any particular island are, of course, practically limited to 

 that one island. That ptarmigan are found upon several islands of the 

 Aleutian chain is due either to the fact that the different islands were at 

 one time connected, thus permitting the ptarmigan to spread over the 

 entire area, or else that individual birds now and then found their way to 

 other islands by being carried across by strong winds. Individuals thus 

 carried to a new island remained there, of course, and, adapting themselves 

 to the new conditions, became well established. In time, the new condi- 

 tions, differing h :>v> ever slightly from those upon the island from which 

 they came, reacted upon these birds and modified them more or less, 

 until finally they became sufficiently differentiated to be easily distin- 

 guished from the ptarmigan of any other island. That differentiation of 

 this character does take place is a well known fact to every student of 

 insular faunas, and the ptarmigan of the Alaskan islands afford excellent 

 illustrations of this important principle. The investigations made by Dr. 

 Stejneger and Prof. Ridgway, some years ago, showed that the ptarmigan 

 of Unalaska Island, of Atka Island, and of Bering Island must be re- 

 garded as three distinct species, or sub-species. 



Unalaska is about 500 miles from Kadiak ; Atka is nearly 400 miles 

 further west ; Attu is 500 miles west of Atka, and about 300 miles south- 

 east of Nikolski on Bering Island. It will thus be seen that the island 

 of Attu is quite as much isolated as are the others named, and I was 

 therefore very anxious to secure specimens of ptarmigan from that island 



