WHAT DO YOUNG ANIMALS KNOW ? 197 



muddy water. This habit is to stand up to the 

 thighs in water, and, stamping gently and rapidly 

 with their webbed feet on the muddy bottom, 

 make the water rise in a constant eddy before them. 

 It brings up any particles of food it may contain, 

 which are then seized and devoured. The writer 

 observed this spring young wild ducks hatched 

 under a domestic hen practising this habit the 

 third day after they had emerged from the egg. 

 They every one stood and watched the muddy 

 water eagerly as it swirled beneath their eyes, 

 stamping rapidly on the bottom meanwhile and 

 snatching continuously at the particles of food as 

 they made them come to the surface. There was 

 an evident knowledge of the action of the water 

 under these complex movements which was quite 

 surprising. No human actions could be better 

 adjusted as a means to an end. The little ducks 

 appeared by their movements and eager looks to 

 know all about the cause and the effect as well as 

 if they had been through the experience a thousand 

 times. And yet they were but three days old ! 

 Some light is thrown on the subject by the actions 

 of a young sheldrake, kept with the ducks, which 

 went through nearly the same movements in search- 

 ing for its food in the same water, but exhibited 

 others quite as interesting. In its natural haunts 

 the sheldrake feeds on the mud-flats and sands left 

 by the receding tide. When it was fed on the dry 

 ground it exhibited a very curious modification of 

 the young wild ducks' habit. It went through a 

 kind of dancing or prancing movement, stamping 

 rapidly on the floor with its feet. The writer was 

 interested to find, on looking the subject up, that 



