332 



LONG-WINGED SWIMMERS — LONGIPENNES. 



3. S. longicaudus. Wing, 11.55-12.85 inches (average, 12.25) ; central rectrices, 10.50-14.50 

 (12.89) ; culnien, 1.10-1.30 (1.19) ; tarsu-s, 1.50-1.80 (1.6C) ; middle toe, 1.08-1.30 (1.20). 

 Tarsi light bluish in adult ; nasal shield not longer than the distance from anterior end of 

 nostril to tip of bill. 



Stercorarius pomarinus. 



THE FOMARINE JAEGER. 



Larus povrariims, TeMiM. Man. Oni. 1815, 511.— Sw. & llicii. F. B. A. II. 1831, 429. Nutt. Man. 



II. 1834, 315. — AuD. Oni. Biog. III. 1835, 396 ; Synop. 1839, 332 ; B. Am. Vll. 1844, 186, pi. 



451. 

 Stercorarius pomarinus, Vieill. Nouv. Diet. XXXII. 1819, 158. — Lawh. in Baird's B. N. Am. 1858, 



838. — Baird, Cat. N. Am. B. 1859, no. 653. 

 Stercorarius pomatorhinus, Newton, Ibis, 1865, 509. — CouES, Key, 1872, 309; Check List, 1873, 



no. 540 ; ed. 2, 1882, no. 765 ; B. N. VV. 1874, 607. — Ridgw. Norn. N. Am. B. 1881, no. 697. 



Hab. Northern portion of northern hemisphere, on the seas and larger inland waters, but 

 chiefly maritime. South, in North America, to New Jersey and the Great Lakes. 



Sp. Char. Adult, lightest jiluise : Pileuni, lores, and malar region, with entire upper surface, 

 except the nape, uniform dark sooty slate, with a slight plumbeous tinge in certain lights ; anal 

 region and crissum uniform plumbeous-slate, sometimes mixed with whitish. Rest of the head 



and neck (including entire nape), and lower 

 parts, except as described, immaculate white, 

 the auricular region more or less deeply tinged 

 with straw-yellow. Bill brownish white (dull 

 brownish in the dried skin), the terminal third 

 black ; iris dark brown ; legs and feet black, 

 sometimes clouded with bluish.^ Adult, usual 

 plumage: Similar to the above, but juguluni 

 and nape barred or transversely spotted with 

 dusky, and the sides irregularly barred with the 

 same. Adult, melanotic phase: Entirely dark 

 sooty slate, with a plumbeous cast in certain 

 lights. Young, light phase : Head, neck, and 

 lower parts dull buff, everywhere barred with 

 dusky ; the bars broad and sharply defined on 

 the crissum and flanks, faint or nearly obsolete 



S. pomarinus. 



on the head and neck. Upper parts brownish dusky, the scapulars and interscapulars tipped with 

 buff, the rump and upper tail-coverts spotted with the same. Young, dark phase : Whole plumage 

 sooty slate, the breast, abdomen, and sides narrowly and rather indistinctly, the crissum and upper 

 tail-coverts broadly and sharply, barred with deep buff. 



Total length, about 20.00 inches; extent, 48.00; wing, 13.50-14.00; tail, 8.00-9.00; culmen, 

 1.45-1.75 ; tarsus, 2.00-2.10 ; middle toe (without claw), 1.60-1.75. 



In the above diagnosis we have described the light and dark extremes of coloration, with an 

 intermediate phase which characterizes perhaps a majority of individuals of this species. Scarcely 

 two specimens are exactly alike, however, in the details of coloration, every condition between the 

 light and dark extremes existing in a large series. 



The Pomarine Skua, or Gull Hunter, is an eminently Arctic species, resident 

 during the summer in high northern regions, chiefly within the Arctic Circle, and 

 extending from Siberia, in Eastern Asia, entirely around the zone. It breeds so 

 exclusively in remote and inaccessible places that bi;t little is comparatively known 

 of its habits at that season. In the fall and in winter it is a great wanderer, and 



1 Adult inale : "Bill blackish brown at the end, dingy j'cllow toward the base; iris brown; tibia, 

 toes, webs, and lower half of tarsus black ; the upper half light blue ; claws black " ( Ai:dubon). 



