By the Riverside 



head and cheeks are white ; the chin, throat, sides 

 and flanks are black, while the rest of the under- 

 parts are white. The second part of the name is 

 equally merited. 



For some reason this Wagtail is a great 

 favourite with the Cuckoo, and often has the 

 doubtful privilege of rearing the latter's offspring. 

 The disparity in their respective eggs is not so 

 great as one would suppose, for the Cuckoo lays 

 an exceedingly small egg considering its size, and 

 one which sometimes bears a singularly close 

 resemblance to those of the Wagtail bluish 

 white, minutely spotted all over with dots of 

 purplish brown. One of the characteristics of 

 the Cuckoo's egg is its extreme variableness, since 

 even blue ones have been found in the nests of 

 the Redstart and Pied Flycatcher, which lay blue 

 eggs. There is every reason to suppose that the 

 Cuckoo that lays these was itself hatched from a 

 blue egg, and continues to lay eggs of this colour, 

 choosing nests of such birds as lay blue eggs in 

 which to deposit its own. Sometimes, however, a 

 Cuckoo's egg is found with others to which it 

 does not bear the slightest resemblance, but the 

 conclusion is that at the time of laying the bird 

 had not found a suitable nest in which to drop it. 

 The egg is first laid on the ground, and then 

 carried in the beak to the nest, where it is to be 

 hatched by proxy ; and the fact that birds have 

 been shot while thus carrying their eggs has 



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