634 LARID^. 



brown, margined with wood brown ; wing-primaries brown- 

 ish-black, tipped with pale brown ; tail-feathers pale 

 brown at the base, then brownish-black to the end ; the 

 central pair half an inch longer than the others ; neck in 

 front, breast, belly, and under tail-coverts pale yellowish 

 wood brown, mottled and transversely barred with umber 

 brown ; legs and the base of the toes yellow, the ends of 

 the toes and the anterior portion of the intervening mem- 

 branes black, and hence called sometimes the Black-toed 

 Gull ; but this is only an indication of youth : as the bird 

 increases in age the yellow colour is lost by degrees. 



The next stage, which in this species, also, as in the 

 Pomarine Skua, probably occurs in the second year, the 

 plumage is of a uniform greyish umber brown, the whole 

 of the light brown margins having disappeared, and the 

 bird has now acquired its full size, measuring from the 

 point of the beak to the end of the long feathers of the 

 tail twenty inches, the central pair of tail-feathers being 

 three inches longer than the next feather on each side ; 

 the wing, from the anterior bend to the end of the 

 longest quill-feather, thirteen inches and three-quarters ; 

 the tarsus one inch and three-quarters ; the middle toe 

 and claw together the same length, or one inch and three- 

 quarters. 



After this stage a few yellow hair-like streaks appear on 

 the sides of the neck ; next, the sides of the neck become 

 lighter in colour : and, advancing in age, the neck, all 

 round, becomes white, tinged with yellow, the head remain- 

 ing of the same colour as the back. Males and females 

 are not distinguishable by their plumage, and as this spe- 

 cies, like the smaller Gulls, is capable of breeding when 

 one year old, it is observed, that birds, sometimes in simi- 

 lar states, and sometimes in very different states, as to 

 plumage, are in pairs at the breeding-stations. 



