EXCEPTIONAL MIGRATION PHENOMENA 125 



ship approached the Irish coast, and made straight for the land. 

 Two others succeeded in escaping from their cage in the streets of 

 Liverpool, and five were safely brought home. Professor Newton, 

 in reference to this case, suggests the opinion that many other 

 migrants may have been thus helped across the Atlantic by human 

 aid ; with what success may be inferred from the American element 

 in the list of so-called ' British ' birds. 



We cannot however reasonably admit that cases like that just 

 instanced explain the passage of American migrants to Europe 

 generally ; for, first of all, as opposed to the three or four birds which 

 regained their liberty near the coast or in the streets of Liverpool, 

 we must take into consideration the numerous flocks which must 

 have passed at the same period over one-half of the Atlantic with- 

 out human assistance, and which certainly would not have retraced 

 their course against the ' stiff westerly breeze ' prevailing at the 

 time, but had probably reached the coast of Europe long before 

 their imprisoned comrades. 



That among the American birds which have been met with on 

 this side the Atlantic, there are examples which, like the aforesaid 

 Crossbills, have escaped from cages, cannot be doubted ; in fact 

 we have already hinted at this in the case of the example of Doli- 

 chonix oryzivora shot here. The number of such birds, however, 

 cannot be more than very insignificant. The simplest way of 

 obtaining a tolerably clear result in this respect is to subject the 

 species of American birds which have occurred in England to a 

 closer examination. 



We shall then find at once that just such of their number as 

 specially commend themselves for the cage or aviary, either by 

 reason of their song, or beauty of plumage, or for being easily 

 sustained with food, are in an insignificantly small minority, while, 

 on the other hand, waders, shore-birds, and aquatic birds are in a 

 majority of ten times the number of the first-named species. Now, 

 these latter birds can only be obtained alive with very great diffi- 

 culty, and would certainly not be kept in confinement otherwise 

 than in rare and exceptional cases ; consequently it is hardly likely 

 that they would ever make a journey to Europe with the aid of 

 human agency. 



The birds comprised in the first of these categories consist of the 

 following species : Turdus migratorius, Regulus calendula, Ampelis 

 cedrorum, Loxia leucoptera, Agelceus phceniceus, Sturnella magna, 

 and Columba migratoria, in all amounting to about twenty-five 

 examples. A widely different result is presented in the case of the 

 waders and shore-birds : thus, of Macrorhamphus griseus fifteen 

 examples are recorded ; of Tringa rufescens and Botaurus lenti- 

 ginosus, seventeen in each case ; while of Tringa maculata as many 



