PERCHING BIRDS. 153 



he communicated his views in the article in question. 

 Dr. Baldamus says he discovered that the cuckoo de- 

 posits her eggs in the nests of thirty-seven different 

 species, and that in by far the greater number of in- 

 stances these eggs bore the same colour and markings 

 as the eggs of the birds in whose nests they were laid. 

 He enters into details, and proves this to his entire 

 satisfaction, giving a list of all the species in whose nests 

 he and his friends found cuckoo's eggs, summing up the 

 question thus : " Therefore I do not hesitate to set 

 forth as a law of nature, that the eggs of the cuckoo are, 

 in a very considerable degree, coloured and marked 

 like the eggs of those birds in whose nests they are 

 about to be laid, in order that they might the less easily 

 be recognised by the foster parents as substituted 

 ones." 



He then asks the question, " Does the same hen 

 cuckoo lay eggs of the same colour and markings 

 only ? and so, is she limited to the nests of but one 

 species ? Or else, does the same individual lay eggs 

 of different colour and markings, according to the 

 character of the eggs amongst which her own will be 

 intruded ?" 



In discussing these points the Doctor considers it by no 

 means " improbable " " that the sight of the eggs lying 

 in the nest has such an influence on the hen which is 

 just about to lay, that the egg which is ready to be laid 

 assumes the colour and markings of those before her/' 

 and adduces as evidence in proof the account of the 

 proceeding of the patriarch Jacob as given in Genesis 

 xxx. 37, &c. 



. His final conclusion, however, is this, " that every hen 

 cuckoo lays only eggs of one colouring, and con* 



