62 THE LIFE OF A BIRD. 



substances, some the most unlikely imaginable, 

 are employed for this purpose. The vegetable, 

 the animal, and even the mineral kingdom all lend 

 some ingredients to the work in hand. It has also 

 been seen that birds make choice of different ma- 

 terials according to the circumstances in which 

 they may be placed. This, and the union in one 

 nest sometimes of one variety of materials, some- 

 times of another, renders it a difficult, and, for 

 practical purposes, a useless task, to classify nests 

 according to the substances of which they happen 

 to be composed. No such classification will hold 

 good throughout ; and it has been only adopted 

 in the present instance merely for the convenience 

 of arranging the parts in order, and with a view 

 to their better recollection. Having marked the 

 situation, and dwelt upon the material, let us now 

 watch our architects in the use of them in the 

 construction of the nest. 



