194 ANNALS OF BIRD LIFE. 



which they come. The general movements of 

 migratory birds are very different in spring to 

 what they are in autumn. In spring, as we have 

 already seen, the great migration is from south to 

 north. No bird is known to migrate north in 

 autumn, but at that season the great movements 

 are from north to south, from north-west to south- 

 east, and from north-east to south-west. Some 

 of our autumn strangers reach the British coasts 

 during their usual passage south ; others, that 

 should travel from the extreme west to the far 

 east, occasionally take the wrong direction, and 

 stray down the Atlantic coasts of Europe ; whilst 

 a great many European species at this season 

 travel from the east to the west ; and sometimes an 

 Asiatic species gets mixed up with them, and is 

 borne westwards with the stream of regular 

 migrants. It is most probable that only the very 

 outermost edge of this vast wave of migrants 

 breaks upon the extreme west of Europe and the 

 British Islands ; so that, though there may be a 

 great number of Asiatic birds carried with it, the 

 bulk of them are scattered over Central and 

 Southern Europe. Most of these birds appear to 

 cross the German Ocean by way of Heligoland. 

 The occurrence of a rare bird on this famous 

 little island at the mouth of the Elbe is a great 

 point in the probabilities of another of that par- 

 ticular species turning up in this country, and 

 helps materially to confirm the bona fides of any 

 stray individual whose occurrence here may be 



