24 INTRODUCTION. 



between the plumage of their foe and the blue hea- 

 ven above them studded with clouds, and passing on 

 fearlessly, they fall an easy prey to his voracious ap- 

 petite, while did the bird present a darker image 

 against the sky, it would produce alarm, and the fish 

 would hurry off to the protection of some overhang- 

 ing bank, or dive into the depths below. 



The instincts of birds are in many respects very 

 remarkable. What sagacity do they display in dis- 

 cerning the proper time for performing their migra- 

 tions ! With what precision do they direct their 

 course through the darkness of night ! With what 

 skill do they construct their nests ! And with what 

 tender affection do they provide for the wants and 

 protection of their young ! It has been observed of 

 the House Wren and many other birds, that the same 

 pair will return to the same spot for many successive 

 seasons: that these little creatures should be able to 

 designate in a journey of at least one thousand miles 

 the precise spot where they have nestled the year be- 

 fore, shows a degree of intelligence not always found 

 even in man. 



The migration of birds is by no means the least 

 interesting part of their history. How often do we 

 observe when looking out upon some bright morning 

 of spring, that while the air seems laden with fresh 

 odors, it also bears upon its bosom a soft aerial music, 

 a sweet incessant warble, the song of thousands of 

 merry little travellers fresh from the distant south ! 

 Each day for weeks in succession seems to bring new 

 arrivals, until at last we welcome the tardy littlo 



