LABID^ 



LAKUS 427 



and pale purple somewhat evenly and densely distributed over the 

 whole surface. They measure about 219 X 142 aoeording to 

 Oates. 



766. Larus cirrhooephalus. Grey-headed Gull. 



Lai-us cirrhocephalus, Vicill. N. Diet. d'Hist. Nat. xxi, p. 502 (1818) ; 



Saimders, Cat. B. M. xx% p. 198 (1896) ; Shelley, B. Afr. i, p. 165 



(1896) ; AUxanxler, Ibis, 1900, p. 442 ; Beichenotv, Vog. Afr. i, p. 44 



(1900). 

 Larus poiocephalus, Sivains. B. W. Afr. ii, p. 245, pi. 29 (1837) ; 



Giirney, Ibis, 1860, p. 221; Layard, B. S. Afr. p. 368 (1867) [in 



part] ; Fleck, Jourv. Omith. 1894, p. 379. 

 Larus phsooephalus, Saunders, P. Z. S. 1874, p. 292, 1878, p. 204 ; 



Slmrpe, ed. Layard's B. S. Afr. p. 698 (1884). 

 Cirrhooephalus poiocephalus, Gumey, in Andersson's B. Damaral. 



p. 358 (1872). 

 Larus poliocephalus, Holuh ^ Pelzeln, Orn. Siid-Afr. p. 832 (1882). 



Description. Adult Male in breeding dress. — Head all round, 

 sides of the face and throat lavender-grey, darkest at its junction 

 with the pure white neck, where there is a marked line of dis- 

 tinction between the two colours ; mantle and wings like the 

 head but a little darker ; two or three outer primaries black with 

 white subterminal marks ; third to fifth with a good deal of white 

 on their basal halves, sixth and others with a considerable quantity 

 of grey, which replaces the white, and gradually takes up the whole 

 feather, seventh with a subterminal black bar throughout life ; tail- 

 coverts, tail and the whole of the lower surface white, a delicate 

 roseate tint, which rapidly fades after death, pervading the whole of 

 the lower surface. 



Iris yellowish-white ; bill and legs crimson to lake-red. 



Length about 16 ; wing 13 ; tail 5'0 ; culmen 1 8 ; tarsus 20. 



The female is slightly smaller ; the adult in non-breeding dress 

 has the head white all round for a short time at least ; the young 

 bird has a white head with darker circular patches, the mantle and 

 wings are somewhat mottled with ashy-brown ; the primaries are as 

 in the adult, but the first two or three have no white subterminal 

 marks ; bill yellowish, blackish at the tip ; legs deep brown. 



Distribution. — The Grey-headed Gull is found over a consider- 

 able portion of South America from Brazil to the Argentine, and 

 across to the coast of Peru. In Africa the same bird ranges from 



