BIRDS OF NORTH AND MIDDLE AMERICA 115 



Sequence of Plumage in Rock Ptarmigan, 1939, 10 (spec.)-— Hellmayr and 

 CoNOVER, Cat. Birds Amer., i, No. 1, 1942, 207 (syn., distr.)— Clark, Smiths. 

 War Background Stud. No. 21, 1945, 78 (list birds Aleutians). 



LAGOPUS MUTUS ATKHENSIS Turner 



Turner's Ptarmigan 



Aditlt male, summer plumage. — There seem to be two fairly distinct 

 color phases of this plumage in this race, as follows : 



1. Reddish phase: Similar to the summer male of L. m. sanfordi but 

 the brownish areas with less of the ashy tinge and with the general ground 

 color darker brown, the lower back and rump pale ochraceous tawny 

 olive ; differs from L. m. townsendi in having more ashy and in being 

 somewhat paler and more tawny. 



2. Olive-brown phase: Similar to the reddish phase but with the 

 ground color Saccardo's umber to pale olive-brown extensively tinged 

 with ashy. 



Adult female, summer plumage. — Like that of L. w. townsendi. This 

 is perhaps the most variable plumage of any of the island races of this 

 species. Probably some of the differences, especially in the longer upper 

 tail coverts, may eventually be found to be a matter of age ; but in our 

 present state of knowledge, this is mere conjecture. 



Autumn adults. — Not yet known. 



Adult male, winter plumage. — All white except for the black loreal 

 stripe which continues behind the eye for a short distance, and for the 

 dark clove brown rectrices narrowly tipped with white. 



Adult female, winter plum-age. — Like that of the male but without the 

 black loreal stripe. 



Juvenal. — Unknown. 



Downy young, male. — Marguerite yellow, slightly washed with pale 

 ochraceous on the breast and abdomen, and marked above with blackish 

 and russet as follows : Narrow median line of black runs from the base 

 of the culmen to the crown where it divides to encircle a large russet 

 coronal patch, and meets again in a broader dorsal band on the nape and 

 upper back ; it divides on the lower back to form two parallel bands which 

 come almost together at the tail end, enclosing a spinal tract of Marguerite 

 yellow much suffused with pale russet ; in addition to these marks there 

 is a blackish femoral band on each side, as well as two wavy ones on each 

 wing and a very narrow line from the bill through the eyes to the hind 

 end of the auriculars. 



Adult male.—Wmg 185-197 (191.2) ; tail 98-112 (109.6) ; bill from 

 anterior end of nostril to tip 9.7-11.3 (9.3) ; width of bill at gape 12-13.1 

 (12.7) ; height of bill at angle of gonys 7.3-8.5 (8 mm.).^^ 



" Twenty-six specimens. 



