X60 THE WHITE-WINGED SILVERY GULL. 



narrow; nostrils in its fore part, lateral, longitudinal, linear, wider anteriorly, 

 open and pervious. Lower mandible with a prominence at the end of the 

 angle, which is long and narrow, the dorsal line then nearly straight and 

 ascending, the sides flat and slightly inclined, the edges sharp and inflected. 



Head rather large. Neck of moderate length. Body rather full. Wings 

 very long. Feet of moderate length, rather slender; tibia bare below; tarsus 

 somewhat compressed, covered before with numerous broad scutella, laterally 

 and behind with roundish scales, on the outer side also with a row of small 

 scutella; toes of moderate length, rather slender, all covered above with 

 scutella; the anterior connected by reticulated webs, the two lateral with an 

 external thick margin; the first extremely small, the third longest, the fourth 

 longer than second; claw of hind toe smallest, of third largest, with an inner 

 thin edge, of second next in size, all more or less compressed and obtuse. 



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

 rather compact. Wings very long, broad, pointed; primaries tapering, the 

 first longest, the second slightly shorter, the rest rapidly graduated; secon- 

 daries broad and rounded, the inner elongated and rather narrow. Tail of 

 moderate length, even, of twelve broad feathers. 



Bill gamboge-yellow, with a spot of orange-red near the end of lower 

 mandible; the angle of the mouth and the edges of the eyelids are also 

 orange-red. Iris pale yellow. Feet pale flesh-colour; claws greyish-brown. 

 The whole plumage is pure white, excepting the back and upper surface of 

 wings; the tips of the secondaries, the terminal third or so of the primaries, 

 their shafts, and the upper tail-coverts also white. 



Length to end of tail 26 inches, to end of wings 28^; extent of wings 50; 

 bill along the back If, along the edges 2\\ tarsus 2\\ middle toe 2j\, its 

 claw y|; wing from flexure 17^; tail 6|-. 



Young in winter. 



Bill yellow, the tips black. Edges of eyelids pale reddish-orange; iris 

 brown. Feet yellowish flesh-colour; claws greyish-brown. The plumage 

 is yellowish-grey, marked on the head and neck with longitudinal streaks of 

 pale brown, on the back and wings with transverse undulations, those on the 

 tail much fainter; the first six quills destitute of markings. 



