xlii INTRODUCTION. 



fairies ; but baffled by storms and contrary gales, they often 

 suffer from want, and at times, like the Quails, become victims 

 to the devouring waves. On such unfortunate occasions (as 

 Mr. Bullock -^ witnessed in a voyage near to Vera Cruz late in 

 autumn) , the famished travellers familiarly crowd the decks of 

 the vessel, in the hope of obtaining rest and a scanty meal 

 preparatory to the conclusion of their unpropitious flight. 



Superficial observers, substituting their own ideas for facts, 

 are ready to conclude, and frequently assert, that the old and 

 young, before leaving, assemble together for mutual departure ; 

 this may be true in many instances, but in as many more a 

 different arrangement obtains. The young, often instinctively 

 vagrant, herd together in separate flocks previous to their 

 departure, and guided alone by the innate monition of Nature, 

 seek neither the aid nor the company of the old ; consequently 

 in some countries flocks of young of particular species are alone 

 observed, and in others, far distant, we recognize the old. 

 From parental aid the juvenile company have obtained all that 

 Nature intended to bestow, — existence and education ; and 

 they are now thrown upon the world among their numerous 

 companions, with no other necessary guide than self-preserving 

 instinct. In Europe it appears that these bands of the young 

 always affect even a warmer climate than the old ; the aeration 

 of their blood not being yet complete, they are more sensible 

 to the rigors of cold. The season of the year has also its effect 

 on the movements of birds ; thus certain species proceed to 

 their northern destination more to the eastward in the spring, 

 and return from it to the south-westward in autumn. 



The habitudes and extent of the migrations of birds admit 

 of considerable variety. Some only fly before the inundating 

 storms of winter, and return with the first dawn of spring ; 

 these do not leave the continent, and only migrate in quest of 

 food when it actually begins to fail. Among these may be 

 named our common Song Sparrow, Chipping Sparrow, Blue- 

 bird, Robin, Pewee, Cedar Bird, Blackbird, Meadow Lark, and 

 many more. Others pass into warmer climates in the autumn, 



1 Travels in Mexico. 



