THE COMMON CROSSBILL. 173 



second moulting that these colours pass into the usual greenish 

 yellow. The red Crossbills are therefore the males of one 

 year old ; the greenish yellow the old birds. 



The females are either grey all over, with a little green on 

 the head, breast, and rump, *or irregularly speckled with the 

 same colours. 



An old male then, as may always be observed in the 

 Thuringian Forest, answers to the following description. It 

 is, however, necessary that the birds should be taken from the 

 nest, and not at the season of departure, when no two exactly 

 resemble one another in colour. This arises from the differ- 

 ent times at which they have moulted, which, as is well 

 known, has a great influence on the colours of birds. 



The forehead, cheeks, and eyebrows are green, or greenish yel- 

 low, spotted with white ; the back Siskin green ; the vent white, 

 spotted with grey ; the shank feathers grey. All over the bird, 

 however, the dark grey colour of the feathers shines through the 

 green and yellow, and gives all the parts, especially the back, 

 n spotty appearance. For in reality, all the feathers are grey, 

 and only their points yellow or green. The wings are blackish ; 

 the small wing coverts green ; the two larger rows, as well as 

 the last quill feathers, bordered at the end with whitish yellow. 

 Ail the quill feathers, however, as well as the black feathers of 

 the tail, have a very narrow border of green. 



If the Crossbills are grey or speckled, they are young ; if 

 red, they are one year old, and have just moulted ; if carmine, 

 they are just about to moult for the second time ; if spotted 

 with red and yellow, they are two years old, and in fall feather. 

 All these differences may be noticed except at the time of lay- 

 ing ; for as they do not make their nest at any fixed season, so 

 neither is their moulting regular, from which arises tne great 

 variety in their appearance. 



Prom all this it follows that the Crossbill has much the same 

 varieties of colour as the Linnet ; and that it is only the red 

 garb, which they wear for a year, which so distinguishes them 

 from other birds. 



It is curious that the young ones, which are bred in aviaries 

 in Thuringia in great numbers, never acquire in confinement the 

 red colour, but in the second year either remain grey, or im- 

 mediately receive the greenish yellow colour of the males who 

 have twice moulted. 



