68 STUDIES IN BIRD-MIGRATION 



Common Gull, Lariis camis. 

 Suiiuner. — Northern Continental Europe. 

 Winter. — Western and Southern Europe, North Africa. 



Herring-Gull, Larus argentatus. 

 Summer. — Coasts of Norway. 

 Winter. — Western and Southern Europe. 



Lesser Black-backed Gull, Larus fiisciis. 

 Summer. — Faroes, Coast of Norway. 



Winter. — Western and Southern Europe to West Coast of Tropical 

 Africa. 



Great Black-backed Gull, Larus marinus. 

 Summer. — Iceland, Northern Continental Europe, Western Siberia. 

 Winter. — Western and Southern Europe, Northern Africa, Canaries. 



Glaucous Gull, Larus glaucus. 

 Sumtner. — Coasts and Islands of Arctic Europe. 

 Winter. — Western and Southern Europe. 



Kittiwake, Rissa tridadyla. 

 Summer. — Coasts and Islands of Northern and Arctic Europe. 

 Winter. — Western and Southern Europe, Canaries. 



Great Skua, Megalestris catarrhactes. 

 Summer. — Iceland, Faroes. 

 Winter. — Western and Southern Europe. 



PoMATORHiNE Skua, Stercorarius pomntorMnus. 

 Summer. — Novaya Zemlya, Tundras of Siberia. 

 Winter. — South-western Europe to South-west coast of Africa. 



Arctic Skua, Stercorarius crepidatus. 

 Summer. — Coasts and Islands of Arctic and Northern Europe, 



Greenland. 

 Winter. — Western and South-western European and African Seas. 



Buffon's or Long-tailed Skua, Stercorarius parasiticus. 

 Summer. — Islands of Arctic Europe, Scandinavia, Greenland. 

 Winter. — South-western European Seas. 



