7346 Birds. 



On the Occurrence of American Birds in Europe. 

 By Heir H. G/ltke* 



The route by which American birds proceed to Europe is, as 

 Yanell justly terms it, " an interesting problem, of difBcult solution." 

 For years this solution has occupied my attention ; and although I 

 have myself always been convinced that such of these entirely 

 American birds as occasionally visit Europe do reach us by a passage 

 across the Atlantic, this remains a mere opinion, carrying no weight 

 if unsupported by facts, or by at least sufficient argument to make 

 good the question at issue. 



The mere comparative review of the occasional visitors among the 

 birds of Great Britain and of Germany will lead to the conclusion 

 that the route of American birds to Europe must needs be a voyage 

 across the Atlantic, for almost all the additions to the birds of Europe, 

 of species purely American, have been obtained in Great Britain, 

 which could not have been the case if they had proceeded in any 

 other than an eastern direction ; whilst the additions by Germany, 

 furnished to the European Ornis, consist nearly entirely of birds 

 belonging to Asia. 



However striking the result of such a comparative review may be, 

 one question will always present itself, namely, whether it be possible 

 for a bird to sustain an uninterrupted flight sufficient to carry it 

 across the wide expanse of the Atlantic. I am convinced that this is 

 possible, and shall endeavour to prove such possibility. 



This purpose necessitates a measure for the rate of locomotion of a 

 bird through the atmosphere. For a long time I vainly endeavoured 

 to obtain reliable data upon which to found an estimation of the rate 

 of flight of birds, when at last I hit upon a passage in Yarrell's 

 * British Birds,' ii. p. 295, where, speaking of the carrier pigeon, he 

 mentions the fact of one of these birds having performed a flight of 

 150 miles in an hour and a half: it was on the 24th of June, 1833; 

 the pigeon flew from Rouen to Ghent ; sixteen others flew the same 

 distance in two hours and a half. 



Wonderful as this instance of swiftness of the flight of a bird may 

 appear, it certainly is still surpassed by birds when on their periodical 

 migrations ; for the above feat was accomplished by an individual 

 hatched and reared in at least semi-confinement, whose powers of 

 flight consequently could not be nearly so well developed as in a bird 



* As translated in the ' Proceedings of iLe Zoological Society' for 1860, p. 105. 



