.THE COMMON-SENSE VIEW 173 



gathering food for a young cow-bird nearly twice 

 as big as she was, while her foundling sat 

 phlegmatically at the foot of a tree chirping and 

 fluttering its wings, and acting as a thankless and 

 apparently bottomless receptacle for the morsel 

 after morsel laboriously harvested for it by its 

 tireless little foster-mother. Sand-martins and 

 kingfishers burrow in the earth and rear their 

 broods in subterranean cradles ; gulls and game- 

 birds build on the ground ; the flamingoes and 

 barn-swallows build mud nests ; the woodpeckers 

 mine holes in trees ; doves and eagles make plat- 

 forms of sticks ; the tailor-bird bastes living leaves 

 together ; the social weavers construct great straw 

 roofs covering the top of a tree, and build their 

 nests on the limbs beneath ; most singing birds 

 build daintily-lined baskets, and swing them in 

 trees and bushes. 



It is often said that all the birds of a species 

 build their nests in precisely the same way, and 

 that, while men change and improve their dwelling- 

 places from generation to generation, birds build 

 their abodes in the same old way, just as their 

 ancestors built theirs centuries and centuries ago. 

 This is a favourite thought with the fogies, with 

 those who change not in their thinking from the 

 ways hacked out for them centuries and centuries 

 ago. Birds are like men. Some of them some 

 races and some individuals are much more given 

 to initiative than others. There is as wide a 

 difference between the hang-bird and the auk in 

 the construction of their domiciles as between the 



