THE SIBERIAN MIGRATION. IQI 



When we come to consider the eastern birds, we 

 have to distinguish between resident species and 

 migratory ones. The Black-throated Thrush (Turdus 

 atrigularis], which has been twice obtained in the 

 British Islands, is a mere straggler to Europe, and 

 is not known to breed there at all. Better known 

 birds, perhaps, are the Golden Thrush ( Turdus varius\ 

 which has even occurred as far west as Ireland, the 

 Rock-Thrush (Monticola saxatilis) and the Scarlet 

 Grosbeak {Carpodacus erythrinus], which breed in 

 Eastern Europe, but are known only as occasional 

 visitors in the west. 



To judge by their distribution, the Bullfinches 

 (Pyrrhula) are of Asiatic origin, for seven species out 

 of ten are confined to that continent. Our common 

 Bullfinch (P. europed] probably came with the Oriental 

 migrants, or perhaps its ancestors did. But the larger 

 Northern or Russian Bullfinch (P. major] has no doubt 

 entered our Continent directly from the east. We have 

 in many groups similar instances of closely allied species 

 er varieties, one of which, originating at a somewhat 

 later stage than the other, took a different route of 

 migration from that followed by its near relative. 



The Pine -Grosbeak (Pimcola enudeator) is only 

 known to British ornithologists as an exceedingly 

 rare visitor. Its real home lies in the northern parts 

 of Europe, Asia, and North America, and it is one 

 of the most typical of the Siberian migrants. 



But there are a number of other species of birds, 

 which, though probably not of Siberian origin, 



