■WILLOW GROUSE. 
219 
■with rusty yellow. Tail with black anti rusty yellow 
wavy transverse streaks. 
By degrees the young become like the mother, as 
the hroAvn wing feathers in August are changed for 
white, and the black tail feathers shoot out. The 
white Aving feathers groAV in this manner: — The outer 
ones of the first and second order come at one time; 
the third and fourth broAvn Aving feathers are shed 
last in the young birds, generally after the middle of 
August. In this or the foregoing month the old birds 
shed their tail and Aving feathers, and in the same or 
beginning of the next month the horny covering on 
the claAvs. 
Male and female in Avinter dress. Beak black; eye 
spot smaller and paler; the fourteen tail feathers black, 
Avith Avhite edges on the ends, A'ery broad on the 
middle ones. The shafts of the fiA^e or six first Aving 
feathers broAvn. For the rest, the Avhole of the 
plumage is snoAV AAdiite; tarsi and toes thickly covered 
Avith bushy feathers, like hair, Avhich, similar to the 
foot of a hare, lie eA^en on the sole of the foot. 
The transition from summer to Avinter dress takes 
place at different times in different jilaccs and seasons, 
but generally in September and October. In the 
middle of the last-named month Ave see some Avhite 
Bipa, and some speckled, on account of some of the 
summer feathers remaining. In the end of April or 
May the spring moult takes place, and even in the 
beginning of June Ave find occasionally Avintcr feathers 
remaining. During the period of transition Ave see 
speckled birds Avith more or less AA'hite feathers among 
the speckled ones. 
The spring moult comes on in this Avay: — The 
coloured feathers first appear on the head and neck. 
