110 A MANUAL OF THE BIRDS OF AUSTRALIA. 
delicate birds to stout heavy forms. They have the leg muscle formula of the Gulls 
but differ in the presence of long czeca and the absence of the expansor secundariorum, 
The coracoids are separated whereas in the preceding they are in contact. The 
most interesting feature, however, is the differentiation of the Antarctic forms as 
to the skull and also in connection with the syrinx. In skull characters the Antarctic 
Skuas are more Pluvialine than Larine and the syrinx is also of the former nature. 
No detailed comparison between these and Stercorarius appears to have been 
instituted. 
Genus CATHARACTA. 
Catharacta Briinnich, Ornith. Boreal., p. 32, (pref. Feb. 20th) 1764. Type (by subsequent 
designation, Reichenbach, Nat. Syst. Vogel, p. v., 1852 (? 1853): Catharacta skua Briinnich, 
Pomarinus G. Fischer, Nat. Mus. Naturg. Paris, Vol. IT., p. 185, (pref. March 6th) 1803. 
Type (by monotypy): Pomarinus fuscus = C. skua Briinnich. 
Megalestris Bonaparte, Comptes Rendus Acad. Sci. Paris, Vol. XLIII., p. 643, Sept. 1856. 
Type (by monotypy): Stercorarius catarrhactes = C. skua Briinnich. 
Buphagus Coues, Proc. Acad. Nat. Sci. Philad., 1863, p. 124, May. Type (by original designa- 
tion): Catharacta skua Briinnich. 
Not Gray, Cat. Gen. Subgen. Birds, p. 129, 1855. 
Largest Skuas with stout powerful hooked bills, long wings, long wedge-shaped 
tail and strong legs and feet with stout hooked claws, the inner claw peculiarly 
developed. The bill has a horny cere, extending half way along the upper mandible, 
overhanging the nostrils which appear as elongately oval apertures ; the tip of the 
mandible is strongly hooked, and the gonys is not very pronounced. The wing is 
long and the square tail is about two-fifths the length, the central feathers being 
normal and not elongated in any way. The legs are very strong, and the feet with 
very broad webs, the claws very hooked, the inner claw powerfully and abnormally 
so, the hind-toe small. 
Coloration uniform dusky above and below. 
77. Catharacta lonnbergimANTARCTIC SKUA. 
Gould, Vol. VII., pl. 21 (pt. xxxv.), Dec. Ist, 1848. Mathews, Vol. II., pt. 5, pl. 122, Jan. 
31st, 1913. 
Catharacta antarctica lonnbergi Mathews, Nov. Zool., Vol. XVIII., p. 212, Jan. 31st, 1912: 
New Zealand Seas. 
DistTRIBUTION.—Southern Australian Seas. 
Adult male-—General colour above dark brown, inclining to blackish on the 
wings ; some of the scapulars fringed and mottled with white, as also some of the 
upper tail-coverts ; wing-coverts uniform dark brown like the bastard-wing and 
primary-coverts ; primary-quills white at the base, dark brown or blackish at the 
tips, the shafts for the greater part white ; secondaries and tail-feathers dark brown, 
white at the base; head and neck all round, rufous-brown like the under-surface 
of the body ; the feathers on the hind-neck and sides of the neck lanceolate in form 
and show glossy shaft-streaks ; under wing-coverts and axillaries darker than the 
abdomen and more glossy ; a short, narrow streak of white below the eye; bill 
black ; iris dark brown; feet black. Total length 690 mm.; culmen (exp.) 57, 
wing, 433, tail 170, tarsus 78. 
Adult female——Similar to the adult male. Total length 610 mm.; culmen 56, 
wing 410, tail 155, tarsus 77. 
Captain Hutton says: ‘‘ Sometimes the feathers of the back of the neck are 
finely streaked with pale yellow ; but usually they are of a uniform brown.” 
Immature —Uniform brownish-black on the upper-surface ; the lower, uniform 
brownish-grey ; the white bases of the primary-quills extensive. 
