NESTING-TIME 



The cliff-swallows, as their name implies, 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 

 numbers. In the eastern states the white-breasted swallow ha- 

 bitually nests in bird boxes in the country and in towns, but the 

 beautiful violet-green swallow of the Pacific Coast still con- 

 tents itself with the primitive nest in a hollow in an oak tree. I 

 might continue at great length to cite cases of birds which have 

 changed their nesting habits, but the examples given are enough 

 to enforce the point. We must therefore look at the birds as 

 genuine architects who work with an intelligent idea of making 

 a home for themselves. We find that their first thought is 

 necessarily of safety, but the loving pains bestowed by the bush- 

 tit and the oriole upon their beautiful homes surely implies a 

 sense of beauty as well as of utility. I cannot but feel, how- 

 ever, that instinct, developed by the habit of generations, plays 

 a part in directing the building of the nests, at least to the ex- 

 tent of impelling the birds to their task. 



The color of the egg seems to be largely determined by the 

 need for protection. We notice that as a general rule birds that 

 nest in the dark lay white eggs, and that the more exposed the 

 nest the more perfectly are the eggs protected in their imitative 

 markings. 



To be sure, there are exceptions to this as to most rules, but 

 think of the woodpeckers and owls. Here are large groups 

 which generally nest in holes in trees and which lay spotless 

 white eggs. On the other hand, many of the sparrows, whose 

 nests are exposed on the ground or in the low bushes, lay green 

 eggs with brown dots upon them. Nothing could blend more 

 perfectly with the green grass or foliage than this, and many a 



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