BONAPARTE’S GULL. 
17 
prominence at the end of the angle, which is long and narrow, the dorsal 
line then ascending and slightly concave, the ridge convex, the sides nearly 
erect and flattened. 
Head of moderate size, ovate, narrowed anteriorly, convex above. Eyes 
of moderate size. Neck rather short. Body rather slender. Wings very 
long. Feet of moderate length, rather strong ; tibia bare below for a short 
space, covered behind with narrow scutella ; tarsus compressed, anteriorly 
covered with numerous scutella and three inferior series of transverse 
scales, laterally with oblong scales, posteriorly with oblique scutella. Toes 
slender, with numerous scutella ; first extremely small, second considerably 
shorter than fourth, third longest ; anterior toes connected by reticulated 
webs, of which the anterior margins are deeply concave, the outer and inner 
slightly marginate. Claws small, compressed, moderately arched, rather 
obtuse, that of middle toe 'with an expanded inner edge. 
Plumage full, close, soft, blended. Wings very long and pointed ; prima- 
ries tapering and rounded, first longest, second very little shorter, the rest 
rapidly graduated ; secondaries obliquely pointed, the rounded extremity 
extending beyond the tip of the shaft, which is exterior to it, the inner 
feathers more elongated. Tail of moderate length, almost even, the middle 
feathers slightly longer. 
Bill black, inside of mouth vermilion. Iris reddish-hazel. Feet orange, 
slightly tinged with vermilion ; claws dusky brown. Head and upper part 
of neck all round, greyish-black, that colour extending half an inch lower 
on the throat than on the occiput. A white band divided by a narrow black 
line margining the eye behind; the remaining part of the neck white ; back, 
scapulars and wings, light greyish-blue. The anterior ridge of the wing, 
alula, smaller coverts on the carpal margin, four outer primary coverts, shaft 
and inner web of the outer primary, both webs of second, inner webs of 
third and fourth, white ; of which colour also are the rump, tail, and all the 
lower parts. Outer web of first quill, excepting a small portion towards the 
end, its tip to the length of half an inch, black, as are the ends of the next 
six, which however have a small tip of white, the black on some of them 
about an inch long, and running along the inner ridge to a considerable 
extent. 
Length to end of tail 14^ inches, to end of wings 151, to end of claws 
13 a ; extent of wings 32£ ; wing from flexure lOf ; tail 4fV ; bill along the 
ridge 1 T V, along the edge of lower mandible ; tarsus ly^ ; hind toe and 
claw ; middle toe 1~, its claw y-j ; outer toe l T J r , its claw f£ ; inner toe 
fi, its claw f|. Weight 6£ oz. 
Adult Female. 
Vol. VIII. — 3 
