986 SYSTEMATIC SYNOPSIS. —LONGIPENNES. 



and pattern of the primaries. Mantle about as in leucopterus ; primaries and secondaries 

 mostly white on exposed surfaces, with markings of dull slate-gray. First primary white on 

 both webs at end for about 2.00, inner web white to base excepting a slate-gray strip next the 

 shaft, outer web (except at end) slate-gray, feding into white toward base ; 2d, the gray con- 

 fined to a space of about 4.00 on outer web, and both webs tinged with color of mantle which^ 

 on inner web, fades into white about 3.00 from tip, but on outer web is deepest where it joins 

 the darker gray area ; 3d with subapical gray bar on both webs, 0.50 wide on inner web, but 

 running along outer web for 2.00 ; tip white, the rest tinged with color of mantle ; 4th with a 

 slate-gray subterminal bar, but narrower and paler; 5th with a pair of subterminal gray spots ; 

 remaining primaries and all secondaries plain, concolor with mantle to within about 2.00 of 

 their tips, where the pearl-blue changes rather abruptly into white. Iris cream-color; bill 

 yellow with red spot, as usual ; orbital ring reddish; feet flesh-color. Length 24.00; extent 

 50.00; wing 16.00-17.00 ; tail 6.50; chord of culmen 1.75 ; gape 2.60 ; tarsus, or middle toe 

 and claw, about 2.30. Cumberland Sound and Greenland, S. in winter to New England and 

 New York. L. glaucescens Kumlien, Bull. U. S. Nat. Mus. No. 15, 1879, p. 98 ; Brews- 

 ter, Bull. Nutt. Orn. Club, 1883, p. 125; Merrill, ibid. Bay of Fundy and Grand Menan. 

 L. knmlieni Brewster, Bull. Nutt. Orn. Club, viii, 1883, p. 216 ; Park, Auk, 1884, p. 196, 

 New York ; Coues, Key, 2d, 3d, and 4th eds. 1884-90, p. 742 ; B. B. and R. Water Birds 

 N. A. ii, 1884, p. 219 ; Ridgw. Man. 1887, p. 27 ; A. 0. U. Lists, 1886 and 1895, No. 45 ; 

 Saunders, Cat. B. Brit. Mus. xxv, 1896, p. 288. 



Ii. nel'soni. (To E. W. Nelson.) Nelson's Gull. Pacific Gray-winged Gull. 

 Coloration as in the last; larger; wing over 17.00; chord of culmen over 2.00 ; bill along 

 gape 3.00 ; its depth at angle 0.80 ; tarsus 3.00 ; middle toe and claw 2.90. Norton Sound,, 

 Alaska ; a dubious Gull, which I admit with hesitation ; but the material now known is in- 

 sufficient for final decision regarding its specific validity or invalidity. It may prove to be 

 chalcopterus of Bruch, Bonaparte, Lawrence, and Coues. L. nelsoni Henshaw, Auk, 

 July, 1884, p. 250 ; B. B. and R. Water Birds N. A. ii, 1884, p. 222 ; A. 0. U. List, 1886, 

 p. 88; Coues, Key, 3d ed. 1887, p. 891; Ridgw. Man. 1887, p. 27; Henshaw, Nelson's- 

 Rep. Alaska, 1887, p. 53; A. 0. U. List, 2d ed. 1895, p. 17, No. 46; Saunders, Cat. B. 

 Brit. Mus. xxv, 1896, p. 287. 



L. mari'nus. (Lat. marinus, marine.) Great Black-backed Gull. Saddle-back. 

 Coffin-carrier. Cobb. Wagell. Size very large; form strong and powerful. Bill 

 very stout, deep at angle, rather short for its height ; culmen toward end exceedingly convex, 

 so much so as to make a tangent to it at the point where the tip of the lower mandible touches 

 it perpendicular to the commissure. Symphyseal eminence very prominent ; tarsus but little 

 if any longer than middle toe and claw, compressed, rather slender for size of the bird. Adult 

 ^ 9 ) i>i breeding plumage : Bill bright chrome ; tip of both mandibles diaphanous. A large 

 bright vermilion spot occupies nearly the terminal half of lower mandible and encroaches a 

 little on the upper. Edges of jaws bright vermilion. Palate and tongue pale orange-red. 

 Eyelids vennilion. Iris pale lemon-yellc)W. Legs and feet pale flesh-color. Mantle intense 

 slate-color, nearly black, with a purplish reflection ; secondaries and tertials broadly tipped 

 with white, the line of demarcation distinct. Primaries : 1st black, scarcely lighter at base, 

 tip white for 2.50, shaft white inferiorly, and superiorly along the white portion of the feather; 

 2d like 1st, but its base lighter, the white tip less extensive, and interrupted by a narrow bar 

 of black on one or both webs ; 3d, 4th, 5th broadly tipped with white, their bases of a lighter 

 shade of slate than the 2d, and fading into white at junction with the broad black subterminal 

 band. Adult J' 9 ; in winter : As in summer, but head and neck streaked with dusky. Young- 

 of-the-year : As large as adult ; bill as large, but not so strong, nor the eminence so well de- 

 veloped ; wholly black. Upper parts dusky chocolate-brown, mottled with whitish and light 

 rufous, the latter on back and wings, the feathers being tipped and wing-coverts deeply in- 



