BIRDS OF THE BRITISH ISLES. 



409 



head and neck jet black, glossed with purple and green ; 

 throat, with two white bands streaked longitudinally with 

 black lines ; sides of chest, white, streaked with black ; 

 upper plumage, mostly black, variegated with rows of white 

 patches and spots ; under parts, white ; sides and flanks, 

 blackish, marked with white ; irides, crimson ; bill, black ; 

 legs and feet, olive-black. Length, from thirty-two to 

 thirty-three inches. The male is larger than the female. 

 In winter the throat-bands are absent. 



Mbite^btUcb Diver. 



JOHN 



THE White-billed Diver (Colymbus Adamst, Gray) is a rare 

 nomadic winter migrant to the British Isles. It inhabits 

 the Circumpolar Region. The adult resembles the great 

 northern diver, but in the former the bill is yellowish-white 

 at all seasons and is deeper ; besides, the under mandible is 



