POMATORHINE SKUA 459 
as far as Walvisch Bay. Eastward this species has been 
obtained in Burmah and Japan ; westward in California and 
Peru, while it has also been recorded in the Southern Hemi- 
sphere from North Australia (Saunders). 
DESCRIPTIVE CHARACTERS. 
PLUMAGE.! Adult male nuptial.—Front and top of head, 
black ; acuminate neck-feathers, white, edged with lght 
yellow ; lower neck, blackish ; back, wings, and tail, brown, 
the two central twisted tail-feathers being four inches longer 
than the rest; breast and upper abdomen, dull white ; lower 
abdomen and under wing-coverts, brown. 
Adult female nuptial.—Similar to the male plumage. 
Adult winter, male and female.—Similar to the nuptial 
plumage, but the feathers of the flanks, upper and under 
tail-coverts, have a tendency to exhibit striations in adult 
birds, not quite mature (Saunders, Cat. Birds Brit. Mus., 
vol. xxv, p. 326). 
Immature, male and female.—Brown, mottled and barred 
with rufous-buff and black ; the markings on the breast and 
abdomen vary gradually from distinct striations to an almost 
uniform brown ; central tail-feathers at first not elongated. 
The mature plumage is very gradually assumed. 
Beak. Horn-colour. 
FEET. Brownish. 
TRIDES. Brown. 
AVERAGE MEASUREMENTS. 
TOTAL LENGTH ... as bal in. 
WING ss... soe a woe, LADO oe 
BRAK) e:. ee ae We MET Gyre 
TARSO-METATARSUS ... ee a 
Kee Ss: ses a Ae Nee 2°6 X 1:8in. 
' Dimorphism, also melanism, occur in the plumage of this Skua. 
