KirrnvAKE gull. i89 



Larus tridacttlus, Lath. Ind. Ornith. vol. ii. p. 817.— CA. Bonaparte, Synopsis of 

 Birds of the United States, p. 359 — Swains, and Richards. Fauna Bor. Amer. 

 part ii. p. 423. 



KiTTiwAKE Gull, Nuitall, Manual, vol. ii. p. 298. 



Adult in Summer. CCXXIV. Fig. 1. 



Bill shorter than the head, strong, nearly straight, compressed. Up- 

 per mandible with the dorsal line nearly straight and slightly declinate, 

 until towards the end, when it is decurved, the ridge convex, the sides 

 slightly convex, the edges a little inflected, straight, towards the end 

 declinate and arched, the tip rather obtuse. Nasal groove narrow rather 

 long ; nostril in its fore part, lateral, longitudinal, linear, wider ante- 

 riorly, open, and pervious. Lower mandible with a slight prominence 

 at the end of the angle, which is long and narrow, the dorsal line then 

 nearly straight and ascending, the sides convex, the edges sharp and 

 inflected. 



Head rather large, oblong, anteriorly compressed. Neck of moderate 

 length. Body rather full. Wings long. Feet of moderate length rather 

 strong; tibia bare below; tarsus somewhat compressed, covered before 

 and behind with numerous broad scutella, the sides reticulated ; hind toe 

 rudimentary, with a minute knob in place of the claw ; the fore toes 

 rather long and slender, the fourth longer than the second, all scutellate 

 above, and connected by reticulated entire membranes, the lateral toes 

 margined externally with a narrow membrane. Claws small, compressed 

 slightly arched, rather obtuse. 



The plumage in general is close, elastic, very soft and blended, on the 

 back somewhat compact. Wings very long, rather broad, acute, the first 

 quill longest, the other primaries rapidly graduated ; secondaries broad 

 and rounded, the inner elongated and narrow. Tail of moderate leno-th 

 even, of twelve rounded feathers. 



Bill pale greenish-yellow. Edges of eyelids crimson; iris reddish- 

 brown. Feet black. The head, neck, rump, tail, and lower parts o-ene- 

 rally are pure white. The back and upper surface of the wings light 

 pearl-grey. The first five quills are black at the end, the first on its outer 

 web also, the fifth with a small white tip, the tips of all the other quills 

 more or less white. 



Length to end of tail 18 inches, to end of wings 20, to end of claws 17 • 

 extent of wings 36^ ; wing from flexure 12, tail 7 ; bill along the back 1 ^ 



