196 



KEY TO THE WATER BIRDS OF FLORIDA. 



STERNA FORSTERI Nutt. 

 Forster's Tern. 



^gg,--^?™-*- Adult in siuiiiiicr: Crown black : upper parts pearl gray : 



^^^^^^ ^H^n^^ under parts white : inner web of outer tail feather 



BMm^^^__^^^^^^^^ darker than outer web ; bill reddish orange tipped with 



MBfi black: feet yellowish. Adult in luinter : Bill dark brown: 



' Y feet brown : head grayish ; a dusky black patch on sides 



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



' Upper parts mottled with pale brown or buff. 



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

 1.50. 



The range of For.ster"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 grav marked with dark brown. 



STERNA HIRUNDO Z/////. 

 Common Tern. Mackerel "QuII.' 



Adu/t 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. 



