INSTINCTS OF BIRDS. 27d 



adapted to the several offices they have to per- 

 form, admits of such numerous and decisive 

 proofs, that it is truly amazing how a person of 

 so much observation as Darwin could so entirely 

 overlook them. 



Those young birds which do not acquire the 

 use of their eyes for several days after they are 

 hatched, open their mouths for food as soon as 

 they are stimulated by hunger, not only when 

 the old ones bring it to them, but when anything 

 approaches the nest. Nestlings too as soon as 

 they are grown sufficiently large, mute over the 

 edge of the nest, though the parent birds carefully 

 convey to a distance whatever drops from them 

 that they do not succeed in ejecting. These 

 actions occur also when birds are brought up in 

 confinement, however young they may be when 

 taken, and therefore must be instinctive. 



The common duck has its toes connected by 

 a strong membrane which enables it to swim 

 with facility; and the young of this species, 

 though hatched under birds which instinctively 

 avoid committing themselves to the water, rush 

 to it with avidity almost as soon as they are 

 extricated from the shell, notwithstanding the 

 utmost exertions of the foster mother to divert 

 them from it. 



