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KEY TO THE WATER BIRDS OF FLORIDA. 



STERNA FORSTERI Nutt. 

 Forster's Tern. 



Adult in siininier: Crown black ; upper parts pearl gray : 

 under parts white ; inner web of outer tail feather 



darker than outer web ; bill reddish orange tipped with 

 black; feet yellowish. Adult in winter : Bill dark brown; 

 feet brown ; head grayish ; a dusky black patch on sides 

 , of the head, enclosing the eye. Immature in winter : 



• I Upper parts mottled with pale brown or buff. 



Length, 15 ; Wing, 10.25 '1 Tail, 6.60 ; Tarsus, .90 ; Bill, 

 1.50. 



The range of Forster's Tern extends nearly 

 throughout North America. It is common in winter in Florida, both on the 

 east and west coast. It breeds commonly on Cobb's Island, Va. ; the eggs 

 are two to three in number, usually laid on the sand ; they are pale buff or 

 greenish gray marked with dark brown. 



STERNA HI RUN DO Linn. 

 Common Tern. Mackerel "Gull.' 



Adult in summer ; Bill red, broadly tipped with black; feet red; crown black ; upper parts 

 pearl gray ; under parts pale ashy gray. Adult in winter : forehead and crown white or grayish 

 white ; under parts white. Immature specimens have the upper parts mottled with buff or pale 

 brown. The outer web of outer tail feather is darker than the inner web at all seasons. 



