IVORY GULL. 



839 



violet- grey. The eggs appear to resemble those of the Kittiwake in colour, 

 but those of the Common Gull in size. 



The Ivory Gull is about the size of the Kittiwake^ but rather less than 

 the Common Gull. When adult^ both in summer and winter^ the Ivory 

 Gull deserves its name, the entire plumage being pure white ; bill greenish 

 grey, yellow at the tip ; legs and feet black ; irides hazel ; orbits vermilion. 

 Immature birds have black spots on the lesser wing-coverts, primary- 

 coverts, the edge of the wing, and on the tips of the quills and tail-feathers. 

 Birds still more immature have black spots also on the mantle, scapulars, 

 and innermost secondaries. Young in first plumage are said to be an 

 almost uniform dark French grey, but very little is known of the imma- 

 ture stages of plumage of this species. Young in down appear to be 

 undescribed. 



