KELLOGG 's PTARMIGAN 229 



Brandt gives a very good description of the eggs as follows : 

 The egg of the rock ptarmigan is ovate to elongate ovate in shape and 

 has slight to considerable luster, which apparently increases as the egg 

 incubates. The surface is smooth and greasy, and the sturdy shell strongly 

 resists the drill. The vivid markings on this beautiful egg are so numerous that 

 they often all but envelope the pale ground color and produce rich-mottled 

 decoration that gives the egg a noteworthy appearance. These spots are dis- 

 tributed evenly over the surface, except that often a confluent cap intensifies 

 the color at the larger end. The eggs laid by one bird are similar in shape, 

 plan of markings, and coloration, but seldom are there two sets from different 

 parents exactly alike. The inconspicuous ground color follows the paler buffs 

 and creams, often with a reddish suggestion ; shell pink, pinkish buff, or cream 

 color is often observed, while many eggs are still lighter than these pale 

 colors. The markings range in size from the smallest spots to those approach- 

 ing thumb-nail in size and are more or less confluent. As a rule, the larger 

 the spots are in size, the more the ground is shown. These markings when 

 dry are blackish brown, but where the pigment has been sufficiently thinned, 

 the color ranges from walnut brown and maroon to blackish brown. Underly- 

 ing spots apparently are not present. 



Behavior. — Doctor Grinnell (1900) says of his experience with 

 this ptarmigan in the Kotzebue Sound region : 



I first met with this species on September 17, 1898, about the summit 

 of the Jade Mountains on the north side of the Kowak Valley. On that 

 day I saw three flocks of 6, 7, and 20 birds, respectively. In each case they 

 were flushed from ridges at some distance, and were probably feeding on 

 heath and blue-berries, which fairly covered the ground on favorable slopes. 

 At. a distance the birds appeared to be entirely white, at this date, though 

 no specimens were obtained. I rather think the summer plumage of the 

 Rock Ptarmigan is of much shorter duration than that of the Willow Ptarmigan 

 in the lowlands. The Rock Ptarmigan, according to my experience, are con- 

 fined exclusively to the higher hill-tops and mountains in summer, and at such 

 elevations the snow remains later in the spring and comes much earlier in 

 the fall than in the valley, leaving a very brief summer. No Rock Ptarmigan 

 were detected in the Kowak Valley until February 11th. On account of the 

 light snow-fall in the early part of the winter, they probably found sufficient 

 forage on the mountain sides up to this date. However, during March and 

 April flocks of from a dozen to a hundred were often met with in the lowlands. 

 These flocks could be traced up by following their tracks, especially if the 

 snow was freshly fallen or laid by the wind. Then tracks of a large flock 

 of Rock Ptarmigan would form a broad swath and extend across the tundra 

 for miles, the individual lines of tracks zigzagging back and forth so as to 

 take in every willow twig or bunch of grass sticking up through the snow, 

 but all tending in the same general direction. The birds, when on these 

 feeding marches, apparently seldom take flight unless disturbed, and I have 

 followed these roads from one set of " forms " in the snow, where the birds 

 had passed the preceding night to the second set of " forms " of the succeeding 

 night, and then finally found them, doubtless on their second day's walk with- 

 out taking flight; except occasional individuals left behind. The tracks of 

 the Rock Ptarmigan are easily distinguishable from those of the Willow Ptarmi- 

 gan by their much smaller size and the shorter strides; and they seem not to 

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