THE CUCKOO. 191 



Cuckoo be somewhat of a vagrant, there is no 

 improbability of her being subject to thus much 

 regularity of habit, and indeed such has been 

 asserted as an observed fact. If, then, this be so, 

 there is every probability of her offspring inheriting 

 the same habit, and the daughter of a Cuckoo which 

 always placed her egg in a Reed Wren's or a Tit- 

 lark's nest doing the like." In other words, the 

 habit of depositing an egg in the nest of a particular 

 species of bird is likely to become hereditary. 



This would be an excellent argument in support 

 of the theory, were it not for one expression, upon 

 which the whole value of the argument seems to us 

 to depend. What is meant by the expression " once 

 successfully deposited " ? Does the Cuckoo ever 

 revisit a nest in which she has placed an egg, and 

 satisfy herself that her offspring is hatched and cared 

 for ? If not (and we believe such an event is not 

 usual, if indeed it has ever been known to occur), 

 then nothing has been gained by the selection of a 

 Reed Wren's or Titlark's nest (as the case may be), 

 and the Cuckoo can have no reason for continuing 

 the practice of using the same kind of nest from one 

 season to another. 



