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he refers, however, as there are remarkably few pecuHar to this 

 part of the continent. 



Without going into a list of American species occurring in 

 Great Britain and Heligoland, a few remarks may be made on 

 the probable manner and route by which they reach their 

 respective localities. 



From the' fact of migrants in narrow seas settling so frequently 

 on the rigging of ships there can be no doubt that many a bird is 

 saved from drowning by this temporary aid, and it is only reason- 

 able to suppose that the presence of certain of the smaller Ameri- 

 can species in Europe has been greatly aided in this manner. 

 Herr Gatke's objection has little weight that the time taken up 

 in resting only adds to the period during which these individuals 

 must go without food. This fact is evident, but still, as he tells 

 us himself, birds migrate on empty stomachs, and on reaching 

 Heligoland, so little are they affected by their efforts, that a stay 

 of only a few hours is sufficient to fully recuperate their powers. 

 A rest, therefore, seems of more value during these long flights 

 than food. 



It is a curious fact and one that should be by no means lost 

 sight of, that the American birds captured in Europe or observed 

 out at sea, have been in nearly all cases single individuals ; very 

 rarely flocks. In the face of this it can hardly be doubted that 

 the majority of the smaller species have been brought over in 

 cages and have escaped on nearing or, on arrival at land. 



Of the larger species, which have occurred in Europe, such 

 as the American Bittern and the various waders, the greater 

 number breed in the far north and no doubt are often carried 

 beyond their proper nesting stations by various influences. The 

 further north they go, the more chance any slight deviation to 

 the east will be likely to convey them to Europe on their return 

 journey. It must not be forgotten too, that as far as we know, 

 there is nothing to prevent these northern breeding species from 

 flying completely across the poles to the breeding grounds of 

 other species which regularly pass our shores on migration. 

 When we reflect how many birds have been observed to stray 

 to great distances beyond their proper quarters — the capture 

 of the Hoopoe in Spitz-Bergen may be cited as an instance of the 

 latter fact — the probability of this assumption becomes apparent. 



