51. HERRING GULL. 24 in. 



(Larus argentatus.) 



White; wings and back, pearly blue-gray; bill mostly 

 yellow; outer wing feathers partly black, marked and tipped 

 with white; the closed wing shows black towards the end, 

 marked with a regular line of w^hite spots and tipped with 

 white at the extreme point; looks large and heavy in flight. 

 Winter : Streaked on head and neck with gray. Immature : 

 Dark, much streaked with brownish; bill darker. Ring- 

 billed Gull. Kittiwake. 



54. RING-BILLED GULL. 19 in. 



(Larus delawarensis.) 



Similar to 51, but sinaller; bill, greenish-yellow, bright 

 at tip, banded with black around the middle; wing tipped at 

 extreme point with black; feet greenish-yellow; eyelids ve-r 

 milion-red. Herring Gull. 



60. BONAPARTE GULL. 13 in. 



(Larus Philadelphia.) 



Back and wings, light pearl-gray; head and throat, dark 

 slate color; back of head, neck, underparts and square tail, 

 white; wings tipped, and bordered narrowly on the outside edge 

 with black; feet and legs, red; bill black. Winter: hood, 

 grayish white. Common Tern. 



70. COMMON TERN. 15 in. 



(Sterna hirundo.) 



Pearly gray back and wings, whiter on rump; top of head, 

 shining black; pure white on throat; dusky-white below; 

 tail forked, outer edge darkest; bill long and red, blackening 

 towards tip, held at right angles to the body in flight; feet 

 reddish. Winter: front of head and under-parts, white; 

 bill nearly black. Bonaparte Gull. 



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