60 THE MIGRATION OF BIRDS 



find companions of quite an alien tribe ; others, 

 wind-swept in this way, may travel alone to new 

 lands. A few pelagic South Pacific and South 

 Atlantic petrels and other birds have reached 

 Europe from time to time, but theirs is an error of 

 too wide nomadic wandering. The wonder is not 

 that these stragglers do turn up, but that so few are 

 noticed ; probably the frequent mistakes made by 

 inexperienced or even experienced birds are speedily 

 rectified by nature ; failure to find food or exhaustion 

 spells death. 



Mr C. Dixon emphatically declares that each 

 party of young birds is accompanied by one or 

 more older ones to act as guides " The many 

 wintered crow that leads the clanging rookery home/' 

 This is as emphatically denied by other observers. 

 Probably there is no regular rule for many species, 

 as there certainly is not for swallows, in which the 

 old and young birds can be easily distinguished. 

 I have seen bands trailing south in autumn in which 

 all the birds were immature, and others in which 

 a number of young were accompanied by a few 

 mature birds, though, certainly, these old birds 

 did not appear to lead. Another assertion, that 

 the old and young do not even travel by the same 

 route rather supports the idea that the young birds 

 find their way simply by a sense of direction, a 

 sense liable to blunder, whilst the old birds travel 



