THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 137 
kennel with three partitions or walls between (doors 
being open) causes one of them, though lying apparently 
asleep, to get up, and if anything happens they all 
awake if one moves much or whines. 
One of them is observed to snap at a fly. 
At 10 p.m. I notice one of the puppies scraping away 
the sawdust near the elevation referred to above, on 
which he had laid his head in preparing to rest. He 
tried the spot once or twice before he finally laid his 
head down. 
42nd day.—lIt is very warm, and the puppies whine 
and cry a good deal owing to the discomfort, as their 
coats are thick and warm. 
Now there are many evidences that they hear as 
acutely as mature dogs, if not more so, and sounds dis- 
turb them more, as they do not know their meaning 
so well. 
They now show an interest in everything that goes 
on within their field of examination with eyes, nose, etc. 
In fact it is difficult to move about among them. 
When they see one they may cry out if hungry, wag 
the tail if recently fed and satisfied, sniff, ete. 
This sniffing is a characteristic method of investigation 
with dogs, and its appearance, at this date and earlies, is 
significant. 
On every occasion, if they see or smell the dam (that 
is seldom with them now, as they were gradually weaned 
—the process ending to-day), they cry out. 
While this litter is an unusually even one in physical 
characteristics, at all events, individual differences are 
to be observed in many directions. There are some 
decided differences in psychic manifestations. 
One, a bitch, seems to be quicker and more precocious 
than the rest by a great deal. 
One dog growls when feeding, as they do at present 
all together from one large dish. 
