LAHUS LEVCOPTERUS. 483 



Primaries and remainder of plumaire, white. Bill, yellow, iris white, and feet, pinkish. In winter, similar hut streaked 

 <;n lii-ail ami noek with nshy-hmwn. Young. Similar to winter adult hut streaked and spotted with ashy-brown. 



OBSERVATIONS. 



Rcco.irni7.eil by tlio large si/o and white primaries. Distributed, in summer, throughout the Arctic Regions, wander- 

 ing sisfar south a>; Ma->uriiusetts in winter. DIMENSIONS. Length, 30*00; stretch, 62-00; wing, 18'50, tail. 8'7fl; bill, 3*00; 

 tarsus, 3'00. 



DESCRIPTION OP NESTS AND EGGS. 



Wests, placed on rock.v cliffs, oomposvd of sticks, sea-weeds, etc. gg>, three or four in number, oval in form, vary- 

 ing from blui<li-white to dark brownish-yi-llow in color, spotted, blotched, and sprinkled with brown and lilac of varying 

 shades. Dimensions from 2'18x2-95 to 2*25x3'00. . 



HABITS. 



The largo and handsome Glaucous Gull is extremely rare- on our New England coast 

 in winter, but is occasionally taken as far south as Massachusetts, both in the adult and 

 immature plumages. I learned, however, when on the Magdalen Islands, that it is quite 

 common there in winter. This bird has much the same habits as those of the larger Gulls. 



LARUS LEUCOPTKRUS. 



White-winged QulL 

 Larus leucopierus FAB., Prodr. Isl. Orn., J820, 91. 



DESCRIPTION. 



Sr. Cu. Size, medium. Form, robust. COLOR. Adult. Back and upper part of wings, pale pearly-blue, with prima- 

 ries nnd remainder of plumage, white. Iris, white, bill, greenish-yellow, and feet, pinkish. Winter adult. Similar but 

 with head and neck narrowly streaked with dusky. Young. Pale yellowish-brown throughout, faintly mottled with 

 darker, and with primaries dusky at tips. Bill, dusky. 



OBSERVATIONS. 



Known by the medium size and pale color. Distributed, in summer, throughout the Arctic Regions. Winters from 

 Massachusetts, northward. DIMENSIONS. Length, 24 '15; stretch, 52*00; wing, 16*75; tail; 6*55: bill, 1*9; tarsus, 2'55. 



DESCRIPTION OF NESTS AND KGGS. 



Nests, placed on/rocky clifls, composed of sticks, sea-weeds, etc. F.yys, from three to four in number, ovul in form, 

 deep brownish-yellow in color, spotted and blotched with rather round marks of brown and lilac of varying shades. Di- 

 mensions from 1 -85x2-70 to 2-()Ox2-7li. 



HABITS. 



On the thirty-first day of January, 1880, an immature White-winged Gull was brought 

 to me by the Bangs Brothers for identification. It was killed while flying over the Mill- 

 dam, in Boston, near Charles River, and another was seen at the same tihie. This is the 

 only specimen of this rare bird that I ever saw in the flesh, and consider it of very uncom- 

 mon occurrence as far south as Massachusetts, as it breeds in the Arctic Regions. 



LARUS MARINUS. 



Great Black-backed Gull. 



Larus marinus LINN., Syst. Nat.. I; 1766, 225. 



DESCRIPTION. 



SP. Cn. Size, very large. Form, robust. COLOR. Adult. Back and win;?s. dark-slaty, becoming black on prima- 

 ries, which with secondaries and tertiaries are broadly tipped with white. Remainderof plumage, white. Iris, yellowish- 

 white, bill, yellow, with a vermilion spot near tip of under mandible, and feet, pinkish. Winter adult. Similar but with 

 lii-ail and neck streaked with dusky. Young. Ashy-brown throughout, more or less mottled with white. Primaries and 

 tail, dusky. Bill, black. 



OBSERVATIONS, 



Known by the larire size and dark colors above, in adult, and rather pale Colors iu young. Distributed in summer from 

 Bay of Fundy, northward. Winters from Maine to Florida 



DIMENSIONS. 



Average measurements of specimens from North America. Length, 30'50; stretch, 65'00; wing, 19*2(1; toil, 8'4H;bill, 



2*38: tarsus, -J s7. longest spceimcn. 31 -(Ml: irrisitiNt extent of wing.GTrlli); longest wing.20'25; tail,!* 05; hill/J-.W; tarmis, 

 3'05. Shortest -penmen, 30-lM), smallest e.Uent of wing. ti-l'(K); shortest wing, 17 8W; -tail, 7 !)H; hill,sJ-2f; tarsus, 2'7;i. 



