Nesting Time, 



although before the introduction of 

 horses the short hairs of the larger wild 

 mammals served the same purpose. 



Another interesting example of a 

 change, due to the advent of civiliza- 

 tion, in nesting habits of a bird is that 

 of the chimney-swift of the eastern 

 states. This species habitually nests in 

 chimneys not in use, fastening its cup 

 of sticks to the sides of the brick flume 

 by means of its gummy saliva. Vaux's 

 swift, a very closely related species 

 found upon the Pacific Coast, has ap- 

 parently not adopted this improvement, 

 and still builds its home in the good 

 old-fashioned way within a hollow tree. 

 The cliff-swallows, as their name im- 

 plies, originally nested upon the face of 

 rocky cliffs, but they find the eaves of 

 our barns a very acceptable substitute 

 and nest in such places in great num- 

 bers. In the eastern states the white- 

 breasted swallow habitually nests in bird 

 boxes in the country and in towns, but 

 the beautiful violet-green swallow of the 

 197 



