144 AETISTS AND AETISANS IN THE FEATHERED WORLD. 



ment, and whenever we speak of nest-builders we at 

 once think of birds' nests. A nest, above all other 

 things, must protect the builders and their young from the 

 influences of weather. It is not only the residence, but 

 the cradle and the kindergarden, and only in rare cases, 

 of which I shall speak later, do birds build certain 

 structures for pleasure and recreation. Nesting is, 

 therefore, a business ; it means " work," which is, in- 

 deed, scrimped if not shirked by some. Consequently 

 we find all degrees of diligence bestowed upon them, 

 and they show all kinds of artistic development, while 

 their size and shape vary in every possible way, so that 

 we may find nests which we could hide in our closed 

 hand, in opposition to structures nearly as high as a grown 

 man ; nests which resist the blow of a hammer, and others 

 which cannot even be touched without crumbling or fall- 

 ing to pieces. Also the forms of the nest are greatly 

 varied ; we have open and cup-shaped, conical, dome-cov- 

 ered and suspended nests, all of which will receive due 

 consideration in the course of this lecture. 



One remarkable circumstance is that sometimes the 

 nearest relatives build very different kinds of nests, or 

 in very different places, while in other cases birds that 

 have nothing in common, construct residences of very 

 similar design. As a strange example of the former may 

 be mentioned the Pyranus, of which one kind, Empi- 

 donax Traillii, builds its nest in a very substantial solid 

 way in the vertical fork of some tree, while his near 

 relative, E. acadicus, always chooses a horizontal fork as 

 the best place for his residence, which is so fragile, with- 

 out any base or support, that one is able to see through 

 it. 



The localities in which nests are placed are extremely 

 variable, the birds seeming sometimes very careless, and 

 again wonderfully capricious in their choice of a proper 

 spot whereon to tit their residences. There is scarcely a 



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