BLACK GUILLEMOT 489 



a narrow alar bar; front of neck, 1 breast, abdomen, and 

 under tail-coverts, white. 



Adult female nuptial. Similar in plumage to the male. 



Adult winter, male and female. The feathers of the 

 throat, cheeks, and chin, are white, but this species " appar- 

 ently does not assume the white patches on each side of 

 the occiput " (W. E. Ogilvie-Grant, Cat. Birds Brit. Mus., 

 vol. xxvi, p. 579). 



Immature, male and female. Resembles the adult 

 winter-plumage. 



BEAK. Black with a white line without feathers 2 along 

 the lower edge of the upper segment (tomia maxillary) from 

 the nostrils to the gape. 



FEET. Brownish. 



IRIDES. Dark brown. 



EGG. Thicker and blunter than that of the Common 

 Guillemot, but very like it in markings : clutch, one. 



AVERAGE MEASUREMENTS. 



TOTAL LENGTH 19 in. Female smaller. 



WING 8-25 



BEAK 3 1-75 



TARSO-METATARSUS ... T5 ,, 

 EGG 3'25 x 2 in. 



BLACK GUILLEMOT. Uria grylle (Linnaeus). 



Coloured Figures. Gould, 'Birds of Great Britain,' vol. v, pi. 

 49 ; Dresser, 'Birds of Europe,' vol. viii, pi. 623 ; Lilford, 

 ' Coloured Figures,' vol. vi, pi. 41. 



The Black Guillemot, a bird of rather local distribution, 

 differs from other British Auks in many of its habits. 4 Far 

 from being gregarious, it is seldom seen, even about its 



1 The white in front of the neck terminates in a point, whereas in 

 the Common Guillemot the white meets the brown in a rounded arch. 



2 In the Common Guillemot this part of the edge of the upper segment 

 of the beak is concealed from view by short dense feathers. 



3 Beak of immature bird much smaller. 



4 By some systematists this bird has been separated from the other 

 Auks, and has been placed in the Genus Cepphus (Saunders). 



