134 BONAPARTE'S GULL. 



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 connnected 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 edge to a considerable 

 extent. 



Length to end of tail 14^ inches, to end of wings 15-f, to end of claws 

 13^; extent of wings 32^; wing from flexure lOf; tail 4 T 2 ^; bill along the 

 ridge 1 T %, along the edge of lower mandible l|f; tarsus ly^; hind toe and 

 claw y|; middle toe 1 T ? 3, its claw ff; outer toe 1-^, its claw f|; inner toe 

 ^4, its claw |f. Weight 6j oz. 



Adult Female. 



