INSTINCT 



but the fact is, that no two nests are alike. 

 A bird will improve in nest building, usually, 

 with age. I have a little friend, a chestnut- 

 sided warbler, that has constructed twenty- 

 three nests since I made her acquaintance. 

 As I remember them the last nest is the neat- 

 est and most substantial. Some have been 

 made almost wholly of rags. Chickadees 

 have adopted cotton-batting, and call for it 

 if I neglect to keep it in the dooryard. It 

 often happens that birds select new material, 

 if handy, instead of hunting the usual nest 

 building material. If birds were guided by 

 instinct and did not exercise reason, they 

 would select the same nesting material year 

 after year. The habit would be so securely 

 fixed that the bird would not be tempted to 

 use new material, no matter how plentiful or 

 handy it might be. The fact that birds read- 

 ily accommodate themselves to new surround- 

 ings, is proof positive that they possess the 

 power to reason. I found a nest, last season, 

 of the wood-thrush, which was a complete de- 

 parture from the usual nest. The bulk of the 

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