Ptarmigan 281 



on the tarsi, and by having the head entirely feathered except sometimes over 

 the eyes. Although as thus circumscribed they form a relatively compact 

 group, there are considerable differences, not only in size, but in certain 

 minor characters, which serve as a basis for separating them into several 

 small well-marked groups that have at times been regarded as of subfamily 

 or even higher rank. In the first of these that we shall consider, embracing 

 the Grouse, Partridges, etc., the nostrils are wholly feathered and the tarsus is 

 half or usually entirely hidden by feathers, while in some the feathering 

 extends quite to the tip of the toes. 



Ptarmigan. Of all the various members of this group none is more inter- 

 esting in many particulars than the Ptarmigan (Lagopus), of which some fifteen 

 species and subspecies are recognized. They are circumpolar in distribution, 

 and while as at present understood are most numerously represented in North 

 America, it is probable that when thoroughly studied, it will be found that the 

 Old World is nearly, if not quite, as rich in recognizable forms. Their most 

 prominent peculiarity is the striking seasonal change of plumage which they 

 undergo, these changes being not only more marked than in any other member 

 of this group, but are perhaps the most pronounced enjoyed by any birds. With 

 one exception, all the species have three or even four, more or less complete 

 changes of plumage, that in winter being chiefly, or entirely, pure white, while 

 at other seasons it is varied with brown, buff, gray, and black. As they live 

 mainly in the, high, Arctic lands or on rugged, snow-covered mountains, these 

 changes admirably adapt them to their surroundings and afford a means of 

 protection from their numerous enemies. To show how strikingly different 

 they are at the various seasons, the following rather full description is given of 

 a male Rock Ptarmigan (Lagopus rupeslris): In winter, as stated above, the 

 plumage is pure white, with the exception of the outer tail-feathers and lores, 

 which are black. In summer the ground color is grayish brown, "coarsely ver- 

 miculated with black, the vermiculations having a tendency to form irregular 

 zigzag bars; the scapulars and interscapulars are largely black centrally, pro- 

 ducing large blotches or irregular spots; the outermost wing-coverts, quills, and 

 secondaries white; lores black; rest of head mixed dusky and white; chest, 

 upper breast, and sides regularly barred with blackish and light umber-brown, 

 while the remainder of the lower parts are white." This gives place in fall to 

 a pale brownish ground-color of the upper parts, variously freckled and spotted, 

 while the wings are much as in the summer condition, and the chest, upper 

 breast, sides, and flanks are much like the upper parts, but are without black 

 spots. The female enjoys a similar change, but is bright ochraceous in summer, 

 irregularly spotted and barred above with black, and is more distantly barred 

 below. These changes are so pronounced, and follow each other with such quick 

 succession, that they have been supposed to lend support to the theory that it was 

 possible to have a change of plumage without moult, but this has been so thor- 

 oughly exploded of late that it is not necessary to further refer to it. Mr. J. G. 

 Millais, who has enjoyed exceptional opportunities of observing the change of 

 plumage in the common European Ptarmigan (L. mutus), has given, in his 



