ON ORNITHOLOGY. 453 
In four very old and perfectly similar birds the iris was 
sulphur to lemon-yellow in colour, the beak waxy yellow, 
the cere somewhat the same, but more inclined to citron- 
yellow, the feet citron-yellow, and the nails black. A fifth 
showed brownish spots, especially on the under part of the 
eye, the iris being sulphur-yellow. 
The Sea-Hagle of Southern Europe differs from the 
Northern Sea-Eagle both in size and colour, but is indis- 
putably the same bird, and there seem to be no grounds what- 
‘ever for making two species of them. They are, however, 
distinct races, such as are often produced among other mem- 
bers of the animal-world by different conditions of life and 
climate. 
In the rich collection of the British Museum I found skins 
of Haliaétus albicilla in all plumages and from the most 
widely separated countries. The northern specimens from 
Scotland, Iceland, Scandinavia, and the north of Russia were all 
markedly larger than those from the South of Europe, Asia 
Minor, and the north of Africa; and the colouring of the 
former was much more pronounced, being darker in the 
young plumage, lighter in the old, and in many cases almost 
white. 
