586 



SYSTEMATIC SYNOPSIS. — GALLING — ALECTOBOPODES. 



568. li. al'bus. (Lat. aTbus, \vhite. Figs. 403, 40i.) Willow Gkouse. Willow Ptarmigan. 

 Bill very stout and convex, its depth at base as much as the distance from nasal fossa to tip ; 

 whole culmen 0.75 ; bill black at all seasons. (? ? , in winter : Snow white ; 14 taU-feathers 

 black, white-tipped ; the middle pair (which most resemble and perhaps are true rcctrices, hav- 

 ing no after-shafts) together with all the coverts, one pair of which reach to end of tail, white; 

 shafts of several outer wing-quills black ; no black stripe on head. ^ , in summer : The head 



Fig. 403. — Willow Ptarmigan, summer plumage, J nat. size. (From Brebm.) 



and fore parts rich chestnut or orange-brown, more tawny-brown on back and ramp; the richer 

 brown parts sparsely, the tawny-brown more closely, barred Avith black ; most of the wings and 

 under parts remaining white. 9 similar, wholly colored excepting the wings, the color more 

 tawny than in the ^, and more heavily, closely, and uniformly barred with black. Length 

 1.5.00-17.00; wing about 8.00; tail 5.50. Arctic and Northern N. Am. from ocean to ocean, 

 int(j the northernmost U. S. Eggs very heavily coltired, with bold confluent blotches of intense 

 burnt sienna color, upon a more or less reddish-tinted buff ground. All the eggs of birds of this 

 family are colorless when tlie shell first forms high in the oviduct, acquiring pigment as they 

 pass down; in the ptarmigan, where the coloring is so heavy, an egg cut from the pigment- 



