196 KEY TO THE WATER BIRDS OF FLORIDA. 
STERNA FORSTERI Wut. 
Forster’s Tern. 
pe Adult in summer: Crown black ; upper parts pearl gray ; 
Mee ion . h 
(Ye under parts white; inner web of outer tail feather 
> ww darker than outer web; bill reddish orange tipped with 
a black; feet yellowish. 4du/t in winter : Bill dark brown; 
/ feet brown; head grayish; a dusky black patch on sides 
of the head, enclosing the eye. Jmature in winter : 
Upper parts mottled with pale brown or buff. 
Length, 15; Wing, 10.25; Tail, 6.60; Tarsus, .go; 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 HIRUNDO Zinn. 
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 7n 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. 
