PTARMIGAN. 271 



flocks known as "packs," the males and females generally form- 

 ing separate parties ; and it is not uncommon to find that all 

 the birds killed in one drive are cocks, while on another beat 

 the reverse obtains. (Grant, I.e.). 



Nest. A slight hollow in the ground, sheltered by the longer 

 heather and grass, and lined with moss and grass or such 

 materials as chance to be on the spot. (Grant, I.e.). 



Eggs. Varying in number from seven to ten and sometimes 

 more. The ground-colour is pale cream or buff, spotted and 

 blotched all over with dark reddish-brown, which often nearly 

 conceals the ground-colour. Average measurements, 175 by 

 1-32 inches. (Grant, I.e.). 



II. THE PTARMIGAN. LAGOPUS MUTUS. 



Lagopus tinereus, Macgill. Brit. B. i. p. 187 (1837). 



Lagopus mutus (Montin) ; Dresser, B. Eur. vii. p. 157, pis. 477, 

 478 (1874); B. O. U. List. Brit. B. p. 144 (1883); 

 Saunders, ed. Yarrell's Brit. B. iii. p. 83 (1883); Lilford, 

 Col. Fig. Brit. B. part iii. (1888) ; Saunders, Man. Brit. 

 B. p. 483 (1889); Grant, Cat. B. Brit. Mus. xxii. p. 44 

 (1893) id. in Allen's Nat. Libr. ix. p. 38 (1895). 



Tetrao mutus, Seebohm, Hist. Brit. B. ii. p. 424 (1884). 



Adult Male and Female at all seasons.* Outer tail-feathers black, 

 with only the bases and tips more or less white ; flight-feathers 

 always white ; bill much more slender than in the Red Grouse 

 or Willow Grouse; wing shorter, males measuring about 7-5 

 inches from the bend of the wing to the end of the longest 

 flight-feather. 



Adult Male and Female, Winter Plumage. General plumage 

 and middle pair of tail-feathers white, with a black patch in 

 front of the eye in the male, which is absent or rudimentary in 

 the female. 



Adult Male, Summer Plumage. Head, upper-parts, middle 

 pair of tail-feathers, sides, and flanks dark brown, mottled and 



* The descriptions are again taken from Mr. Ogilvie Grant's volume (/.<".). 



