676 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
b. Axillars and under wing-coverts grayish brown, slightly tinged ‘with cinnamon- 
rufous; under parts more grayish brown than rufescent. (Northern part of 
North Atlantic Ocean.).............0202.0202 2 eee Megalestris skua (p. 677). 
bb. Axillars and under wing-coverts mostly cinnamon or cinnamon-rufous; under 
parts uniform dull cinnamon-rufous or cinnamon. (Both coasts of southern 
South America, from Rio de Janeiro on Atlantic side to Callao, Peru, on 
Pacific side.).... « Diver iene a Aon Gime eee Megalestris chilensis (extralimital).¢ 
aa. Bill relatively shorter and deeper, with anterior edge of supra-nasal saddle (viewed 
from above) slightly concave; under. parts sooty brown to buffy brown (not at 
all rufescent). 
b. Under parts dark sooty brown; neck not conspicuously, if at all, streaked with 
yellow; white patch on base of primaries smaller. (Falkland Islands, South 
Georgia Island, Gough Island, Straits of Magellan, and adjacent seas. 
Megalestris antarcticus (extralimital).} 
3. Megalestris chilensis. (Catharacta chilensis Mathews, Birds Australia, ii, pt. 
5, Jan. 31, 1913, 496.—West coast of South America.) 
4. Megalestris maccormicki maccormicki. (Catharacta maccormicki maccormicki 
Mathews, Birds Australia, li, pt. 5, Jan. 31, 1913, 496.—South Victoria Land.) 
5. Megalestris maccormicki wilsoni. (Catharacta maccormicki wilsont Mathews, 
Birds Australia, ii, pt. 5, Jan. 31, 1913, 495, 496 —Weddell Sea.) 
6. Megalestris .lonnbergi lonnbergi. (Catharacta antarctica lonnbergi Mathews, 
Novit. Zool., xviii, 1912, 212; New Zealand seas.—Catharacta lonnbergi lonn- 
bergi Mathews, Birds Australia, ii, pt. 5, Jan. 31, 1916, 484, 494, 496.— 
Megalestris antarctica (not Lestris antarcticus Lesson) Mathews, Birds Aus- 
tralia, ii, 1913, pl. [122] facing p. 484.—Australian and New Zealand seas, 
breeding on Chatham Islands and Antarctic islands of New. Zealand.) 
7. Megalestris lonnbergi intercedens. (Catharacta lonnbergi intercedens Mathews, 
Birds Australia, ii, pt. 5, Jan. 31, 1913, 496.—Kerguelen Island.) 
8. Megalestris lonnbergi clarkei. (Catharacta lonnbergi clarket Mathews, Birds 
Australia, ii, pt. 5, Jan. 31, 1913, 494, 496 —South Orkney Islands.) 
Of these forms I have seen only the first, third, and seventh. 
. 4 [Stercorarius antarcticus} b. chilensis Bonaparte, Consp. Gen. Av., ii, 1857, 207 
(South America; coll. Berlin Mus.).—Stercorarius chilensis Saunders, Proc. Zool. Soc. 
Lond., 1876, 323, pl. 24 (monogr.); 1877, 800 (Straits of Magellan); Cat. Birds Brit. 
Mus., xxv, 1896, 318.— M[egalestris] chilensis Ridgway, Man. N. Am. Birds, 1887, 21.— 
Catharacta chilensis Mathews, Birds Australia, ii, pt. 5, Jan. 31, 1913, 496. 
5 Lestris antarcticus Lesson, Traité d’Orn., 1831, 616 (Falkland Islands).—Ster- 
corarius antarcticus Gray, List Birds Brit. Mus., Anseres, 1844, 167; Saunders, Proc. 
Zool. Soc. Lond., 1876, 321, part (monogr.).—Catarracta antarctica Bonaparte, Nau- 
mannia, 1854, 210.—Catarrhactes antarcticus Bruch, Journ. fiir Orn., 1853, 108.— 
Catharacta antarctica Lénnberg, Kungl. Svensk. Vet. Handl., Bd. 40, no. 5, 1906, 58 
(South Georgia Island; crit., habits, etc.).— Megalestris antarcticus Gould, Proc. Zool. 
Soc. Lond., 1859, 98 (Falkland Islands).— Megalestris antarctica Saunders, Cat. Birds 
Brit. Mus., xxv, 1896, 319, part (Inaccessible Island, off Tristan da Cunha; Falkland 
Islands).—Megalestris skua antarctica (not of Baird, Brewer, and Ridgway, 1884.) 
Mathews, Birds Australia, ii, 1913, 496 (Falkland Islands, breeding; Gough Island).— 
Buphagus antarcticus Coues, Proc. Ac. Nat. Sci. Phila., 1863, 127 (monogr.); Birds 
Northwest, 1874, 604, part (monogr,).—Lestris antarctica Sclater and Salvin, Ibis, 
1869, 284 (Santa Magdalena, Straits of Magellan).— Megalestris skua falklandica Lénn- 
berg, Schwed. Sud. Exped., Bd. v, Lfg. 5, 1905, 8. 
