LARUS ICHTHYAETUS. 



(THE GREAT BLACK-HEADED GULL.) 



Larus ichthyaetus, Pallas, It. ii. App. no. 27 (1776); Blyth, Cat. B. Mus. A. S. B. p. 288 

 (1849) ; Layard, Ann. & Mag. Nat. Hist. 1854, xiv. p. 270 ; Shelley, B. of Egypt, p. 307, 

 pi. 13 (1872); Dresser, B. of Europe, pt. 18 (1873); Hume, Str. Feath. 1873, p. 276, 

 et 1879, p. 115 (List B. of Ind.) ; Von Heuglin, Orn. N.Ost-Afr. ii. p. 1401 (1873); 

 Legge, Str. Feath. 1875, p. 375 ; Saunders, P. Z. S. 1878, p. 198. 



Kroikocephalus ichthyaetus (Pall.), Jerdon, B. of Ind. iii. p. 831 (1864). 



Croicocephalus ichthyaetus (Pall.), Holdsw. P. Z. S. 1872, p. 480. 



Adult (Caspian). Wing 18-3 inches ; tail 6-5 ; tarsus 3-0 ; middle toe and claw 3-4 ; bill to gape 3-5. 

 (Volga.) Wing 19-5 inches ; tail 8-6 ; tarsus 3-1 ; middle toe 2-3, its claw 05 ; bill to gape 4-0, depth 0-9. 



Adult male (Sindh). " Length 29-95 inches ; wing 19-5 ; tail 7-5 ; tarsus 3-2 ; middle toe and claw 2-55 ; bill t'r, 

 gape 3-8; weight 2 lb. Wing in 12 males 19-0 to 20-0 ; in 5 females 18-5 to 18-9." {Hume.) 



'OIll 



Breeding-plumage. Iris brown ; gape and eyelids vermilion; bill rich orange or wax-yellow, with a black bar across 

 both mandibles between the tip and the gonys ; " legs and feet rich yellow, with a greenish tinge " (Tristram). 



Entire head and throat to the level of just beneath the nape glossy black, sharply defined all round against the white 

 of the neck and entire under surface, the tail and its coverts ; back, interscapulary region, and wing-coveri s 

 delicate blue-grey ; scapulars and tertials tipped with white ; primaries and their coverts white, the 1st quill with 

 a black edge to within 2| inches of the tip, adjacent to which is a black band across the inner web ; at the same 

 position there is a black band across the next four quills, more extensive on the outer web than the inner ; 6th 

 primary with a black mark on the inner web near the tip. 



In specimens which are probably very old the edge only of the outer web of the 1st primary is black. 



Winter plumage. Bill yellower than in summer, the terminal portion orange-red. 



Head, face, and throat white, a black bordering in front of the eye ; nape and sides of the head behind the eye marked 

 with dusky grey streaks. 



The summer plumage is donned very early in the season. Mr. Hume writes that specimens shot in Sindh in the 

 latter half of January had white throats, and some of them slightly blackish-mottled caps ; but others killed at 

 Muscat in the middle of February " were in the fullest breeding-plumage, the whole head and neck all round 

 being velvet-black." 



Young, in down (Volga: coll. Saunders). Bill black, with the tip yellow ; legs and feet brown. 

 Entire upper surface dingy white, tinged with fulvous ; throat tinged with grey ; under surface white. 



Plumage of first winter (Ceylon). Head and all beneath white, with a dark spot in front of the eye : the hind neck 

 and back, with the bases of the feathers, pale, the central portions pale earthy brown, and the tips fulvous : 

 scapulars ochraceous brown, with fulvous-white tips ; lesser wing-coverts dark grey-brown; median coverts brown, 

 paling into ochraceous brown, and thence into greyish at the margins ; greater series ash-brown, darker in the 

 centre, and with whitish margins ; primaries aud their coverts blackish brown, paling to whitish at the bases of 

 the inner webs, with the tips of the shorter feathers white ; secondaries glossy umber-brown, the major portion of the 

 inner webs, the tips for about half an inch, aud the terminal portion of the edge of the outer webs white ; sides 

 iif rump, upper tail-coverts, and two thirds of the tail from the base white, the extreme tips of all the feathers 

 white : under tail-coverts with a black bar | inch from the tip, reduced on the lateral feathers to an oval spot on 

 the outer web ; under wing brown along the edge, the median series of feathers spotted with the same. 



Bill dark brown, paling behind the nostril and at the base of the lower mandible ; legs and feet dusky yellow. 



in tin: second year, judging from a specimen before me, killed in Ceylon while moulting, the hind neck is spotted with 



