THE BIED INVISIBLE. .227 



us why they get the name. Do not look for the black-billed 

 cuckoo west of the Rocky Mountains, nor for the yellow-billed 

 at the farthest northern limits of the country, for it is rare 

 north of Massachusetts. In the farthest South there is some- 

 times seen a third kind called the Mangrove cuckoo. When 

 both kinds are found in the same region, the black-billed will 

 be most commonly detected along wet lowlands, where a little 

 growth of willows or alders borders a meadowy rivulet, while 

 the yellow-billed cuckoo haunts the dry upland pastures, with 

 scattered tufts of shrubby trees and near access to taller, 

 thicker growth. 



Some day you may find Cuckoo's nest. Cuckoo is a poor 

 nest builder, so you may easily guess whose house it is 

 even if the owner is not home. "As a nest builder," says 

 one observer, "the cuckoo is no genius, or if a genius he 

 belongs to the impressionist school. The nest is but a raft of 

 sticks flung into the fork of a bough." If you find such a nest, 

 so shallow that the pale, blue-green eggs may easily be rolled 

 out if the wind blows hard, thrust into the side of a quickset 

 hedge, or on the low bough of an evergreen, there is little doubt 

 it is Cuckoo's. She usually further advertises herself by twist- 

 ing a piece of rag into her structure, just as the red-eyed vireo 

 always uses a piece of hornet's nest, and the Baltimore oriole 

 twists strings into her woven pocket, and the great-crested fly- 

 catcher wreathes a snakeskin about her nest rim. 



It is not wise to go too near Cuckoo's nest, nor to visit it 

 often. She is the most suspicious of mothers, and often deserts 

 her nest when she finds that it has been discovered. Instead, 

 keep away from the pretty green eggs and the ugly black babies 

 until some day you see Madam Cuckoo bringing caterpillars to 

 what you think are little Plymouth Rock chickens. Then you 

 may watch her if you will. Naturally you will be rather aston- 



