Geographical Distribution 353 



most of Central Asia and Siberia to the Pacific at about 

 Lat. 55 . It consists of two Provinces, viz. — 



A. The European Province. 



To this belongs the whole of Northern and Central 

 Europe, as defined above, and Central Siberia as far as the 

 valley of the Lena. The Bearded Reedling of our Norfolk 

 Broads (Calamophilus biarmicus) is one of the characteristic 

 forms, but numbers of species do not wander outside the 

 limits of this Province. The Ural Mountains, which have 

 been generally looked upon as the boundary of the 

 European Avifauna, are no boundary at all, and few species 

 of birds seem thus to regard it. Whether the Yenesei or 

 the Lena constitutes the eastern limit of the European 

 Province can only be determined •when we know more of 

 the birds which inhabit the valley of the last-named river. 

 Many species of European birds apparently do not extend 

 beyond the Yenesei Valley, and in Central Siberia there is 

 probably a distinct natural Province, judging from many 

 of its birds. Thus the Starlings {Sturnus) are represented 

 in the European Province by our common species, Sturnus 

 vulgaris, but in Central Siberia its place is taken by 

 Sturnus menzbieri, while no true Sturnus is found 

 beyond the district of Lake Baikal. The Blue-headed 

 Wagtail of Europe {Motacilla flava) is represented on the 

 Yenesei by a paler species {M. beemd), and the Hooded 

 Crow (Corone sharpii) is again a paler form of our European 

 Hooded Crow (C. comix). There are also many other 

 representative species and an infusion of peculiar forms in 

 Central Siberia which may ultimately warrant the recogni- 

 tion of a third Province in our Eurasian Sub-Region, but 

 at present the data are wanting, from which to found a 

 decisive conclusion. 



A A 



