430 THE RING-BILLED Gi'LL. 



gonys, and sharp cutting edges; tail generally even; body 

 thick, and wings broad, as compared with the Terns, for 

 instance, while they are usually of larger size; feet and legs 

 stout for birds of their class; and the bouyancy with which 

 they float on the water, on account of their small bodies as 

 compared with the bulk of their plumage. In form, gener- 

 ally, the whole sub-family are so similarly moulded, that 

 any eye of moderate discrimination can recognize them. 

 In size and color they are subject to great variation. 



