7 46 SYSTEM A TIC SYNOPSIS. — L ONGIPENNES — GA VIuE. 
to the feathers. Head, neck, and under parts, mottled with white and dusky. Primaries 
uniformly black ; secondaries with a patch of brownish-hlack near the ends ; tertials wholly 
brownish-black, narrowly tipped with whitish. Tail with a broad subterminal band of black, 
narrowly tipped with white. Terminal half of bill black, the extreme tip yellowish. Young- 
of-the-year in August : Everywhere mottled thickly with brownish-black, on the upper parts 
the feathers with yellowish -white edges, the pearl-blue of the adults scarcely apparent, except 
on the wing-coverts. Terminal two-thirds of bill with the tip black, the rest light flesh - 
color. Dimensions: length 19.75; extent 48.50; wing 14.75; bill above 1.70; gape 2.30; 
height at nostril 0.45; at angle 0.50; tarsus 2.10; middle toe 1.80. N. Am. at large, on 
the whole the commonest species, both coastwise and in the interior ; breeds in the U. S. as 
well as far north, 
779. L. ca'nus. (Lat. canus, hoary gray.) European Mew Gull. Assigned to N. A. on 
strength of a specimen shot by me in Labrador in 1860. It is entirely like the next to be 
described excepting the following particulars : Tarsus a fourth longer than the middle toe and 
claw. Bill stouter, with less convex culmen and better developed angle. The bluish bases of 
the primaries darker, not fading into white at their junction with the black, not running so far 
along the feathers, nor farther in the centres than along the edges of the inner webs. Size 
greater. Probably not more than varietally distinct from the next to be described. 
780. L. brachyrhyn'chiis. (Grr. ^paxvs, brachus, short; pvyxos, hrugchos, beak.) American 
Mew Gull. Bill small, somewhat stout for its length, much shorter than the head or tarsus. 
Upper mandible straight to the end of the nostrils, moderately convex to the tip, rather more 
so than in canus. Angle of lower mandible pretty well-developed, comparatively more so than 
in canus ; the lower outline considerably concave posterior to it, somewhat so before it. 
Commissure about straight to near the tip. Tarsus and middle toe and claw about equal, the 
former but little if any longer than the latter. Adult in summer : Bill bluish-green, its ter- 
minal third bright yellow. Legs and feet dusky bluish -green, the webs yellowish. Mantle light 
grayish-blue or dark pearl-blue, a shade darker than in canus, much darker than in delawa- 
rensis. Primaries : the bluish-gray bases rather lighter than in canus, much darker than in 
delawarensis, but fading into nearly pure white on all but the first at the juncture with the 
black portion ; these bluish -gray bases of the feathers extend toward the ends much further 
than in canus, as far as in delawarensis, and, as in that species, on the 2d, 3d, and 4th, extend 
further along the central portions of the inner web than at the edges, so that they are bordered 
for some distance with the black of the terminal portions of the feathers. The black takes in 
the outer web of the 1st primary and nearly the whole of the inner, but rapidly becomes nar- 
rower, till it is merely a subterminal transverse bar on the 6th. The 7th has frequently a spot 
of black on one or both webs. First, with a large white spot near the end two inches long, 
longer on the outer than on the inner web, not divided by the black shaft, the tip of the feather 
black ; 2d, wdth a similar spot, but smaller, not longer on the outer than on the inner vv^eb, 
and divided by the black shaft ; the extreme apex white, as are the apices of all the other 
primaries except the 1st. Adult, high breeding plumage : Eyelid, ocular region, and gape of 
mouth, bright orange-yellow, which color extends over the tip and cutting edges of the bill. 
The green of the bill with a peculiar hoary glaucescence. Legs and feet bluish-green, the 
webs bright gamboge-yellow. Sometimes a faint pink blush of the plumage of the under 
parts. Adult in winter : The head and neck all round, with the upper part of the breast, mot- 
tled with dusky. Approaching maturity : Head and neck faintly mottled. Primaries brown- 
ish-black, without decided white tips ; the spots on the 1st and 2d restricted. Tertials with a 
dusky spot on each web near the end. Tail with a more or less perfect subterminal band. 
Young, first winter : Bill flesh -color ; black on the terminal half. Legs and feet light yellow- 
ish. Head, neck, rump, and whole under parts, mottled irregularly with dusky. Back as in 
the adult, but the feathers with grayish edgings. Wing-coverts, secondaries, and tertials 
