THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 123 
16th day—Can discover little advance in vision. 
The eyes are still more fully open. 
If the puppies hear at all it is only in the faintest 
way. 
As the dam stands close beside the pen, when the 
puppies lie drowsing, they soon begin to move the 
muscles of the face, raise their. heads, sniff here and 
there, like a hunting dog catching scent of game, and 
feel about, as it were, for the object giving the scent. 
Presently they make, almost simultaneously, quick 
movements as if to reach some object. I am convinced 
that all this is from smell and not vision, though it 
would be difficult to prove absolutely that sight had 
nothing to do with it. 
When the dam now sits on her haunches the puppies 
manage to reach the teats. 
They will still suck the finger when put into the 
mouth, but for a much shorter period. 
17th day—Playing more common. One began to 
play with the foot of another, but soon changed to 
sucking this part. 
Slight movements of the tail are noticed during play 
at times, and there is obvious increase in walking 
power; muscular co-ordinations of all kinds are better 
made. 
When a beef bone is held within half an inch of the 
nose when the puppies are asleep, the movements of 
tongue, lips, ete. before referred to as evidence of 
smell, take place. When awake, they give evidence 
of smelling cold roast beef at 3 inches. 
When the dam stands at the end of the pen, some 
2 feet from the puppies, that lie in about its centre, 
they soon begin to move towards her, but not in a 
straight line, as they would if they were guided solely 
by sight. I am convinced that vision is very im- 
perfect yet. 
