142 



NATURAL HISTORY. 



lowland ranges which the Eed Grouse and Willow Grouse frequent ; and hence the present species 

 appears somewhat less numerous than the latter bird. Should an intruder make his appearance in 

 the home of the Ptarmigan, or should a bird of prey appear, they squat and remain motionless, 

 trusting chiefly to the similarity of their plumage to the ground and the herbage to enable them 

 to escape unseen. Should one litter his croaking note, he is generally on a stone ready to take winy 

 at a moment's notice, and when he rises and calls all the rest of the covey join him. So close do they 

 squat, and so well does their plumage harmonise at all seasons of the year with the surroundings, that 

 one may walk through a covey without being aware of the close proximity of a single individual. In 

 the month of July, according to Macgillivray, and in October, according to Earth and other Scandi- 

 navian naturalists, the Ptarmigans begin to collect in packs, and are found in lower altitudes than in 



PTARMIGAN IN SUMMER PLUMAGE. 



the summer season. Barth says they do not unfrequently visit the sea-coast, and, being white, are 

 very conspicuous ; they appear quite bewildered, and easy to approach within gunshot, whereas, when 

 the ground is covered with snow, they are shy and take wing before one has arrived within anything 

 like gunshot range. They fly tolerably swiftly, in a loose irregular body, their mode of flight resem- 

 bling that of the Red Grouse, and when once on the wing, will generally fly some distance before 

 settling. Their call note is a harsh croak, not unlike the croak of a frog, and it is frequently uttered 

 as an alarm call. The food of the present species consists chiefly of the tender twigs and leaves of 

 Eiiipetrum nigrum ; but Macgillivray says that the crops of specimens he examined contained a large 

 quantity of fresh green twigs of Calluna vulyaris, Vacciniuni myrtillus, and Empetrum nigrum, the 

 largest fragments not exceeding five-twelfths of an inch in length. Leaves and twigs of Vacciniuni 

 vitis-Idcca, Salix herbacea, seeds of various Juncce and Cyperacece, and other plants, with berries in 

 autumn, also form part of their food, the same as that of the Red Grouse. The Grey Ptarmigan, then, 

 is a bird which, feeding on vegetable substances, containing comparatively little nourishment, 

 introduces a large quantity at a time, like a ruminating quadruped, and gradually digests it while 

 reposing." 



In summer the Ptarmigan puts off his white dress and becomes dark-coloured, not unlike a Willow 



