THE Gos-Hawk. 121 
on wing, and can secure their own prey, the old birds drive them off, and they 
begin their wanderings towards the south. 
In their immature plumage (in which they are so often taken for Golden 
Eagles) they are dark brown, mottled with fulvous on the mantle and wings; tail 
dark brown; beak black; cere and irides light brown. The full plumage is not 
attained until the fifth or sixth year. 
A very large example of an old bird received from the Isle of Lewis was very 
light in colour, being of a yellowish grey all over. The writer has seen one of 
a uniform silvery white, that was shot near Glasgow; in this specimen the 
plumage was much abraded, and it gave the impression of being of a great age. 
Very old birds are said to become bluish grey upon the mantle. In the museum 
at Dunrobin Castle there is a perfect albino that had pink eyes. 
Family—FALCONID.F.. 
Gos-Hawk (ze. GoosE-Hawk.) 
Astur palumbarius, LINN. 
HIS fierce and rapacious bird is now only known in the British Isles as a 
rare occasional visitor at the periods of migration, when a chance one puts 
in an appearance from the Continent generally on the eastern coasts, and most 
frequently during the autumn and winter; these stragglers are mostly immature 
birds. "The last one known to the writer was one seen by his brother, Mr. G. F. 
Mathew, R.N., near Harwich, one day in the winter of 1895. Stevenson writes : 
“The Gos-Hawk appears occasionally (in Norfolk) both in spring and autumn, 
but at uncertain intervals, and has of late years become even more scarce than 
formerly.” At the beginning of the century there were a few pairs of Gos-Hawks 
nesting in the great forests of Scotland, but in Macgillivray’s time they had 
Vor. III U 
