LABTB^ — LAMINA: GULLS. T45 



flesh-color); ring round eye in the breeding season orange-red (not yellow). Mantle dark 

 bluish — much darker than that of argentatus, yet not slate-colored as in occidentalis. Europe, 

 Asia, and N. W. coast of N. A. 



T76. Li. affi'nis. (Lat. affinis, allied to L. fuscus.) Rbinhardt's Gull. Unknown to me ; 

 Described as a slaty-backed bird, resembling L. fuscus, but belonging to the herring gull 

 group in the pattern of the primaries ; feet flesh-colored, small, toes shorter than tarsi. Asia ; 

 only N. American as occurring in Alaska and accidentally in Greenland. 



Tn. L. caUfor'nicus. Californian Gull. Adult, summer plumage : Bill moderately stout, 

 the angle well developed ; varying in size, longer than in delawarensis, sometimes nearly equal- 

 ling argentatus. Tarsus equal to or slightly longer than middle toe and claw. BiU chrome- 

 yellow, tinged with greenish; a vermilion spot on lower mandible at angle ; a black spot just 

 above, forming, with a very small black spot on the upper mandible, an imperfect transverse 

 band. Feet dusky hUdsh-green, the webs yellow. Mantle pearl-blue, much as in hrachyrhyn- 

 chus, lighter than in canus, slightly darker than in eargentatm. Primaries : bases of aU light 

 bluish- white, internally almost' white, especially on outer webs, and of great extent on all; 1st 

 with a white space at the end for about 2 inches, the shaft white along the white portion of 

 the feather ; 3d with a white spot near the end on the whole of the inner and most of the 

 outer web, divided by the black shaft ; tips of all white ; black forming merely a narrow sub- 

 terminal band on the 6th. Tips of inner primaries white, as are also the tips of the second- 

 aries and tertials, the line of demarcation between the white and the blue of the mantle pretty 

 distinct. In breeding plumage : Eyelids bright saflFron-yellow or red. Eyes brown. Upper 

 mandible bright chrome, the greater part of the lower vermilion, the rest chrome. Gape of 

 mouth deep crimson. Feet gi-een. Winter plumage: Bill dully colored. Head and neck 

 behind streaked and mottled with dusky. Nearly mature : As in the preceding. Tail with 

 an imperfect subterminal black bar. Some of the feathers of the upper parts edged with gray. 

 White space at end of 1st primary crossed by a transverse black bar ; no spot on 2d primary. 

 Young: Bill yellowish flesh-color, black on the terminal half. Head, neck, rump, wing- 

 coverts, tertials and secondaries, mottled with dusky. Primaries and tail uniformly brownish- 

 black, scarcely lighter at the tips. Back as in the adults, but the feathers with grayish edges. 

 Dimensions: Length 20.00-23.00; extent 50.00-54.00; wing 15.00-17.00; bill 1.60-2.00; 

 depth at eminentia symphysis 0.56; tarsus 2.00-2.25; middle toe and claw about the same. 

 Adults near the larger of these dimensions. Western and Arctic N. Am., breeding abundantly 

 in U. S. 



T78. L. delawareu'sis. (Of Delaware.) Ring-billed Gull. Common American Gull. 

 Adult in summer : Bill rather stout, as long as the middle toe and claw ; the upper mandible 

 considerably convex at the end ; under mandible much thickened at the angle, which is prom- 

 inent ; the outline from base to angle, and from angle to tip, both concave. Middle toe and 

 claw scarcely more than f the tarsus. Bill greenish-yellow, at tip chrome, encircled at the 

 angle with a broad band of black. Legs and feet dusky bluish-green. Mantle light pearl- 

 blue, fading into white at the ends of the secondaries and tertials, the line of demarcation in- 

 distinct. Primaries : 1st black, the basal portion of the inner web very light bluish-white, 

 (almost white), with a spot of white about 1.25 inches long near the end, of equal extent on both 

 webs, divided by the black shaft ; 2d with a small white spot on the inner web, and the inner 

 web whitish at base for a longer distance ; the whitish of the bases of the primaries regularly 

 increases inward and the black decreases, until on the 6th it is merely a transverse bar. Apex 

 of 1st primary black, of others white, the spot being very minute on the 2d, and gradually in- 

 creasing; 7th and innermost primaries without any black, like the secondaries. Adult in 

 winter : As in summer, but the head and neck behind spotted (not streaked nor nebulated) 

 with dusky. Young, first winter : Upper parts irregularly mottled with dusky brown and the 

 pearl-blue of the adults, the wing-coverts being almost entirely dusky, with lighter margins 



