The Body of a Bird 



291 



than we now possess of the life-habits and the psychology 

 of birds. This is especially true of the great number of 

 cases which we can explain only by calling them orna- 

 mental and decorative. Hence we find one ornithologist 



FIG. 231. White-throated Sparrows. The light-coloured bird is in normal plu- 

 mage; the dark bird was subjected to moisture-laden air through two moults. 



explaining a certain colour as due to one cause, while 

 another scientist gives an entirely different interpretation 

 of the same fact. 



From personal observation among the birds of the 



