240 RESULTS OF THE JOURNEY 



geographically or ornithologically. So far as we know, 

 one species only of the Petchora birds recognises this 

 chain as the eastern limit of its range, viz. : 



Meadow Pipit. 



Four species ranging westward from Kamtschatka 

 throughout Arctic Siberia and across the Ural Mountains, 

 do not appear to advance farther into Europe, during the 

 breeding season, than the valley of the Petchora : 



Siberian Pipit. Siberian Stonechat. 



Yellow-headed Wagtail. Bewick's Swan. 



Six species, ranging westward from Kamtschatka 

 throughout Arctic Siberia and across the Ural Mountains, 

 appear to extend beyond the valley of the Petchora as 

 far as the White Sea, viz. : 



Siberian Lesser-spotted Woodpecker. Marsh-tit (eastern form). 

 Little Bunting. Terek Sandpiper. 



Arctic Willow-warbler. Siberian Herring-gull. 



One bird only appears to be so restricted in its 

 geographical range as to be found only in the valleys of 

 the Petchora, the Ob, and the Yenesei, viz. : 



Siberian Chiffchaff. 



Of the fourteen birds included in the last four lists, 

 only four or five have their principal breeding-grounds 

 within the Arctic circle, and these all belong to genera 

 which are represented in the Nearctic region, with the 

 exception of the Arctic willow-warbler, which has been 

 obtained in Alaska. 



The final conclusion to which we must therefore 

 arrive, from a study of the geographical distribution of 

 the birds found in the valley of the Petchora, is that a 

 circumpolar region ought to be recognised : that so iar 



