114 BIRDS OF THE WORLD 



Gulls 



At one time regarded as near relatives of the Pet- 

 rels, it is now known that these birds are much more 

 closely related to the Plovers, and this relationship is 

 shown, curiously enough, most strikingly in the 

 colouration of the eggs on the one hand and in the 

 skeleton on the other, though many other common ana- 

 tomical characters afford equally positive evidence of 

 this fact. 



Like the Petrels and unlike the Plovers, they are 

 web-footed. But they differ from the Petrels and 

 resemble the Plovers in having slit-like instead of 

 tubular nostrils. 



Such species as display a distinct summer dress 

 have this change confined to the colouration of the 

 head. Many species require several years to attain 

 their fully adult plumage. 



Gulls fly with more deliberate flaps of the wings 

 than Terns and Jaegers and are able to keep in the air 

 even longer without coming to the water to rest. It 

 is believed that individuals have followed vessels en- 

 tirely across the Atlantic. Gulls are excellent swim- 

 mers, exceedingly buoyant and floating high on the 

 waves with the breast seeming just to touch. One 

 alighting upon the water is a very pretty sight, indeed. 

 Raising the wings high above the back as it nears 

 the surface, with the delicate feet extended down- 

 ward, the bird settles quietly to rest, folding its wings 

 and carefully adjusting its plumage. They sleep or 

 appear to sleep in the wildest sea, bobbing up and 

 down on the waves like corks, and no amount of spray 



