GEEAT BLACK-HEADED GULL 419 



DESCRIPTIVE CHARACTERS. 



PLUMAGE. Adult male nuptial. Head, black, with a 

 small white patch above the eye and another below ; back 

 and wings, ' pearl ' grey ; primaries, white towards their 

 tips, tinged with light 'french' grey above; there is a 

 narrow streak of black along the outer web of the first 

 primary ; neck, breast, abdomen, and tail, white. 



Adult female nuptial. Similar to the male plumage. 



Adult winter, male and female. Differs from, the 

 nuptial plumage in that the head is white, streaked with 

 greyish-brown and black, chiefly about the eye and the ear- 

 coverts. 



Immature, male and female. Head, streaked with dark 

 greyish-brown ; wing-coverts and scapulars, mottled with 

 dark brown ; tail, white, banded towards the extremity with 

 dark brown. 



" Birds which have assumed the black hood for the first 

 time exhibit black streaks next the shafts of the primaries 

 1 3 and black bars on 1 5, until the following moult " 

 (Saunders). 



BEAK. Eed, with a darkish band in front of the angle ; 

 strongly built. 



FEET. Ked. 



IRIDES. Dark brown. 



EGGS. Dull white shading to cream, blotched and 

 streaked with dark brown : clutch, two to three. 



AVERAGE MEASUREMENTS. 



TOTAL LENGTH 15*5 in. 



WING 11-75 



BEAK 1'75 



TARSO-METATARSUS 1-9 ,, 



EGG ... 2-2 X 1-4 in. 



GREAT BLACK-HEADED GULL. Larus ichthyaetus (Pallas). 



Coloured Figures. Dresser, ' Birds of Europe,' vol. viii, pi. 598 ; 

 Lilford, ' Coloured Figures,' vol. vi, pi. 21. 



There appears to be but one British record of this 

 South-eastern species, the largest of the ' hooded ' Gulls. 



