WHITE-TAILED EAGLE. 15 



One in the British Museum, supposed from its small size 

 to be a male, measures much less than the female above de- 

 scribed. The beak is two inches from the forehead to the 

 tip, and three inches from the tip to the gape ; the long- 

 est quill-feather of the wing seventeen inches. This spe- 

 cimen resembles very nearly the brown one represented in 

 the plate, with the exception of the upper coverts of the 

 tail, which are dark chocolate, two or three only being a 

 little mottled with white ; the tail is pure white. It would 

 thus appear that the upper tail-coverts are the last part of the 

 plumage that attains maturity. Mr. Selby describes a bird in 

 his possession as having " the tail, and upper tail-coverts 

 white ; " while Dr. Latham, on the authority of Dr. Hey- 

 sham, says, that an individual which had been kept in con- 

 finement, was " six or seven years before the tail became 

 white." This species goes through many interesting changes 

 of colour in the course of its progress from the nestling to 

 a state of maturity. We are informed by Montague, speak- 

 ing of some young birds that he had obtained from the coun- 

 ty of Down, that " the Eaglets were at first covered with a 

 glossy, dark, murrey-coloured down ; on their first moulting 

 they became much darker, particularly about the breast and 

 thighs, the latter almost of a dusky black, and it was not 

 until they were two years old that the base of the bill became 

 yellow.'" In this dark state of plumage the iris is umber 

 brown ; and it is not until the upper tail-coverts begin to 

 assume the white colour, indicative of maturity, that the iris 

 becomes yellow, tinged with burnt sienna. 



In this species the lower part of the tarsus is bare of fea- 

 thers, scutellated in front, the hinder part reticulated ; the 

 claws are grooved beneath. The beak is long, straight at 

 the base, and bending from the cere to the tip ; the gape 

 extends nearly as far as the hinder corner of the eye. 



