246 THE MIGRATION OF BRITISH BIRDS 



to the British Area in spring has been reported and 

 described by Mr. Cordeaux as a " very anomalous 

 movement." If it were perfectly normal it certainly 

 would deserve such a description. There can be no 

 doubt whatever that the individuals coming from the 

 north-east and east (most probably the former) into 

 England, in the very teeth of the advancing normal 

 migration from Britain to the Continent, are birds that 

 have migrated too early, or that a sudden late snap of 

 winter in their summer quarters, or on the routes to 

 them, has turned back. We experience precisely the 

 same phenomenon in the Arctic regions of birds being 

 too eager to reach their breeding grounds, and having 

 to return, it may be, many miles, owing to a temporary 

 recurrence of winter weather. It would be just as 

 manifestly absurd to say that there was a migration in 

 the Arctic regions soiitJi as Aveli as north in spring, as 

 it is to describe this east to west or north-east to south- 

 west flight at the same season on and off our eastern 

 coasts (conf. Migration Report, v. pp. 60, 61). It is 

 suggestive enough that no such " anomaly " occurs in 

 autumn ! 



During the earlier part of the time this spring migra- 

 tion is in progress of birds leaving us for continental 

 areas, another, if perhaps less perceptible movement of 

 some of the same species is taking place into our islands 

 from more southerly areas : individuals that breed with 

 us and still continue to winter further south. This 

 movement is not a very ancient one. It is made by the 

 descendants of individuals of these species that were 

 among the last to extend their summer area to the 

 Ikitish Islands. It was initiated after Ireland was 



