190 THE MIGRATION OF BIRDS. 



China and Malaysia, birds that have obviously 

 increased their summer area westwards within 

 comparatively recent time. Birds visiting the East 

 Palaearctic region, from the Urals or the Obb 

 valley to Kamtschatka and the Aleutians, normally 

 winter in Arabia, Persia, and India, eastwards to 

 China^ and southwards to Australia and New 

 Zealand ; but a few in a precisely similar way 

 retire to Asia Minor and Africa, birds that have 

 extended their sunimer area eastwards within 

 equally recent time. The winter quarters of 

 West Palcearctic migrants may be divided into 

 three well-marked regions or zones. The first 

 of these zones is the Great Aquatic Zone, con- 

 sisting of the North Sea, the Baltic, the West 

 Atlantic down to Madeira, the Mediterranean, the 

 Black and the Caspian Seas, the Red Sea, and 

 part of the valley of the Nile. The second of 

 these zones may be said to include the extreme 

 southern portions of Europe, Turkey in Asia, 

 Persia, the Arabian Peninsula, and all Africa north 

 of the Equator. The third of these zones consists 

 of Africa south of the Equator, including Mada- 

 gascar. The first or aquatic zone is the great 

 winter quarters of West Palaearctic migratory 

 water birds, especially Swans, Geese, and Ducks 

 (ANATiD.i:), Grebes (Podicipedid.^), and various 

 Waders (Charadriid.e). As might naturally be 

 expected, the land birds wintering in the extreme 

 northern portions of the second zone, between 

 South Europe say and the Atlas, are few. Among 



