( 2 ) 

 THE ECLIPSE-PLUMAGE OF THE CAPERCAILLIE. 



With a Note on the Capercaillies in the 

 Pennant Collection. 



BY 



W. R. OGIL VIE -GRANT. 



The difficulty of obtaining game-birds during the nesting- 

 season and when they are undergoing their autumn- 

 moult, has caused several interesting seasonal changes 

 of plumage to be overlooked until comparatively recent 

 years. Thus, it was not until the summer of 1912 when, 

 through the kindness of the Marquess of Breadalbane, 

 I received several male Capercaillies in full moult, that 

 I was able to show that this species, like the Blackcock, 



assumes an ecKpse-plumage 

 in July and August. At 

 that season the sides of the 

 head and neck are covered 

 with short blackish feathers 

 mottled with pale sandy- 

 brown (fig. a) and the chin 

 and throat are clad in worn 

 old black feathers devoid of 

 green gloss and mingled with 



a. Eclipse-plumage ou sides of the shortcr morc rouudcd eclipsc- 



b. WinterXnagerLes of the feathcrS sHgMly SpCCklcd with 



head aiid neck. ^^y Qn tho sldcS of the 



head and neck, a few of the long pointed feathers of the 

 breeding-plumage (fig. h) are usually retained and are very 

 conspicuous among the short echpse-feathers. The latter 

 differ so little in general tint from the feathers of the 

 winter- and breeding-plumage, which are grey mottled 

 mth black, that it is difficult to see what advantage the 

 bird derives from the change. Possibly it is the survival 

 of an ancient plumage worn by the ancestral stock, 

 before the long pointed ornamental feathers on the sides 

 of the head and throat had been developed in the modern 

 bird. The eclipse-plumage of the Capercaillie was first 



