Order LARIF0EME8 
No. 153. 
Family LARIDjF. 
GABIANUS PACIFIGUS GEORGII. 
WESTERN PACIFIC GULL. 
(Plate 121.)* 
Larus GEORGII King, Survey Intertrop. Coasts Austr., Vol. II., p. 423, 1826 ; King 
George Sound, West Australia. 
Larus georgii King, Survey Intertrop. Coasts Austr., Vol. II., p. 423, 1826. 
Gabianus pacificus Gibson, Emu, Vol. IX., p. 77, 1909. 
Larus paci ficus Ogilvie-Grant, Ibis 1910, p. 184. 
Larus pacificus georgii Mathews, Nov. Zool., Vol. XVIII., p. 212, 1912. 
Distribution. South-west Australia. 
Adult male. Back and wings dark brown ; small coverts round the bend of the wing 
pure white ; lesser, median, and greater wing-coverts blackish hke the bastard- 
wing, primary-coverts and quills, some of the latter tipped with white, more 
broadly on the innermost primaries which are also margined with white on the 
inner webs towards the tip ; sides of rump, upper tail-coverts, and tail white, 
the latter with a broad subterminal band of black on all the feathers except the 
outer pair, each of which have a very shght motthng of black and a black shaft- 
streak on the subterminal portion of the feather ; head and neck all round white 
like the under surface, which includes the axillaries, under wing-coverts, and 
under tail-coverts ; “ Bill green, tip red, cutting edges yellowish green ; iris silvery 
white ; eyehd yellow ; feet yellow ” (J. T. Tunney). Total length 645 mm. ; 
culmen 62, wing 475, tail 192, tarsus 78. * 
Adult female. Similar to the adult male but the sub terminal black band on the tail 
much more irregular in shape, the outer feathers pure white with the exception of 
the subterminal black shaft-streak, the second pair has a slight mark on the outer 
web with a black shaft-streak and a large blotch on the inner web, while on the 
corresponding feather there is only a black shaft- streak and a small black spot 
on the inner web ; “ Iris brown ” (J. T. Tunney). Total length 645 mm. ; culmen 
60, wing 443, tail 178, tarsus 64. 
Immature. Upper surface brown, most of the feathers margined with white or ferru- 
ginous, and showing dark shaft-streaks on the scapulars and upper tail-coverts ; 
bastard-wing, primary-coverts and quills dark brown fringed and tipped with 
white, the shafts of the latter white on their basal portion ; secondaries similar but 
paler at the base of the inner web ; tail-feathers dark brown fringed with whitish 
at the tips, outer feather on one side margined with white, and white on the inner 
web at the base ; head and neck all round brown with white bases to the feathers ; 
throat white with brown pear-shaped spots to the feathers ; remainder of under 
surface brown with white bases to the feathers ; under wing-coverts dark browui ; 
axillaries uniform pale brown. 
* The Plate is lettered Oahianus pacifktus. 
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