The Birds' Calendar 



eluding observation, not only by placing them 

 in concealment, but by making the exterior of 

 the nest so harmonious in color and texture 

 with its surroundings, that it is sometimes 

 scarcely discernible even when close before 

 your eyes. It often seems as if the chronic 

 anxiety and ceaseless vigilance of these creat- 

 ures to escape destruction would make life 

 hardly worth living. 

 Even in winter, 



" When there is a hush of music on the air." 



you commonly hear a chirp or zip before you 

 see the bird, and not infrequently these call- 

 notes are distinctive enough to indicate the 

 species. This is perhaps especially true of the 

 winter birds, when the various families are rep- 

 resented by so few species, and the more re- 

 mote the relationship the more unlike the notes 

 are likely to be. For example, the white- 

 throated sparrow has a peculiar and unmistak- 

 able tone, soft, but shrill, as unlike that of the 

 cardinal grosbeak or of the nuthatch as possible, 

 although not easily distinguished from the note 

 of some of the species appearing later in the 

 season. Indeed, without these faint sugges- 



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