GULLS. 395 



B. With white head, both summer and winter, but 

 in the winter the heads of some are spotted brown. 



1. With white back. 



230. L. EBURNEUS, Gm. Hvit Mase. The Ivory Gull. 



D. F. 



Length 20 in. ; beak, from the nostrils, 6 1. ; tarsus 

 1 in. 4i 1. shorter than the middle toe ; foot web in- 

 dented. The whole plumage ivory white, with black, 

 rough, short legs ; beak large, grey -blue, with yellow 

 tip ; the first primary longer than the following. The 

 young bird has small black spots on the wings, thicker 

 on the head ; a black band at the point of the tail ; 

 beak blackish, with yellow tip. 



Has never been detected breeding in any part of Scan- 

 dinavia, but is only occasionally seen off the coast in the 

 winter. 



Morris gives a very good figure of the egg of the ivory 

 gull. I have not seen many, and all these have been from 

 Greenland. Ground colour reddish white, covered all over 

 with large and small red-brown spots. I know no gulFs 

 egg so light in colour. Eather larger than that of the last. 



2. With ash blue back ; both in summer and winter 

 all the under parts white. 



231. L. TEYDACTYLUS, L. Tretaig Mase. The Kittiwake. 



D. F. 



The absence of the hind toe will distinguish this at 



once from any other gull. Mantle ash blue ; tarsus 



If in. ; the outer primaries black, with white tips ; 



bill green-yellow; legs dark olive green; length 18 in.; 



wings 2 in. longer than tail ; beak from forehead If in. 



Except as accidental wanderers, they seem to be confined 



entirely to the Polar seas on these coasts. 



232. L. CANUS, L. Fisk Mase. The Common Gull. D. F. 



Length 17-^-in. ; beak, from forehead, If in.; the 

 older the bird grows, the higher and more bent at 

 the tip does the beak become ; tail about 2 in. shorter 



