236 BULLETIN 16 2, UNITED STATES NATIONAL MUSEUM 



out the substance of the nest, though more numerous upon its surface, where a 

 dozen or so are deposited ; there may have been some loose ones lost in 

 handling. 



Illustrating the perfectly concealing coloration of the bird on its 

 open nest, Evan Lewis (1904) writes: 



On reaching timber-line a Junco was seen building, and a search was made 

 for a loose stone to mark the spot for a photograph when the set was com- 

 plete. In the search I was just about to put my hand on a Ptarmigan when 

 I saw what it was. I then made two exposures with the small camera and 

 left the camera on top of a large rock to mark the spot, the nest being three 

 steps and one foot due south from the mark. I went to the cabin at the lake 

 and got the large camera and tripod. When I returned I took three rather 

 shorter steps, as I supposed, and looked for the bird or its nest. For ten 

 minutes I looked over the ground foot by foot. I could not believe my own eyes 

 that the bird was not there, yet I could not see her. At last I was about to 

 return to the mark and step the ground over again, when a reflection from the 

 bird's eye showed her to me just one foot from where I was standing. 



W. C. Bradbury (1915) had some similar experiences. Nests, 

 which he had previously located and marked, he had difficulty in find- 

 ing again even when standing within a few feet of them. One nest 

 was right beside a stone that his foot was on ; but it had been lightly 

 covered with grass when the bird left it. In one case he found that 

 only three eggs had been deposited in a period of five days. 



Eggs. — The white-tailed ptarmigan has been credited with laying 

 as many as 15 eggs and as few as 1 ; probably the usual numbers run 

 from 6 to 8. In shape they vary from ovate to elongate-ovate, and 

 they have little or no gloss. They are quite unlike other ptarmigans' 

 eggs and are colored more like small eggs of the dusky grouse. The 

 ground color is usually " cartridge buff " or "pinkish buff " and 

 rarely " cinnamon-buff." The lightest-colored eggs are sometimes 

 nearly immaculate ; most of the eggs are more or less evenly covered 

 with small spots or fine dots; some are more heavily marked with 

 larger spots or small blotches; but the ground is never largely con- 

 cealed. The markings are in various shades of brown, usually very 

 dark brown, " Vandyke brown " to " bone brown," but sometimes as 

 light as " snuff brown " or " tawny-olive." The markings are rarely 

 concentrated into a ring. The measurements of 31 eggs average 42.9 

 by 29.5 millimeters; the eggs showing the four extremes measure 49.3 

 by 29.6, 44.7 by 32.3, 39 by 28.3, and 42.9 by 28.2 millimeters. 



Young. — Mrs. Bailey's (1918) account of the behavior of mother 

 and young is worth quoting, as follows: 



Listening, I caught it again — the softest possible call of a mother ptarmigan ! 

 There she stood, only a few feet from me, hard to see except when in motion, so 

 well was she disguised by her buffy ground color finely streaked with gray. 

 A round-bodied little grouse with a small head, she was surrounded by a 

 brood of downy chicks, evidently just hatched, as their bills still held the sharp 

 projection for pipping the shell. Preoccupied with the task of looking after 



