THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 145 
23rd day.—Playing. Differences in coat, shape of head, . 
etc., showing a physical advance. 
They now dite and chew at objects. They show a decided 
aversion to Epsom salts. 
25th day.—Began feeding milk. They do fairly well at 
first attempt to lap. 
26th day.—They push through some slats confining them, 
showing considerable co-ordinative power, etc. 
30th day.—Repeated and rapid pinching of their sides 
makes them very angry—snatl, etc. 
The fall of a shovel causes them all to cower with fear. 
32nd day.—Lip-call followed by their approach with 
wagging tail. 
37th day.—The sound of a whip surprises and seems to 
puzzle them. 
45th day.—When about to punish another mature terrier 
they hide away under the benches. 
They are put down in the yard, a large one, for the first 
time, and seem puzzled and shy. 
46th day.— Great changes now visible in physical features, 
expression of face (more knowing), etc. They now crowd 
each other when eating from the same dish. Their move- 
ments and whole demeanour more terrier-like. This is seen 
in play very clearly. 
They are now much more readily and profoundly affected 
by noises. 
47th day.—Rapid development owing to enlarged ez- 
perience ; much more aggressive. 
50th day.—Two of them given bones. Each goes off with 
one. When one comes up to take the other’s, he pulls it 
away but does not growl. Lies down to bone and uses his 
feet to steady it like a mature dog. When the boue is 
snatched up the puppy snzfs about after it. 
Sexual and individual differences now more evident—I 
mean that the peculiarities of shape, expression, and 
demeanour that characterise a mature bitch, and which only 
close observers of dogs detect, are now fairly well developed. 
58th day.—When looking out into darkness at night they 
show hesitation, fear, etc. 
The discussion that follows is based almost entirely 
on the diary of the litter of St Bernard puppies, ex- 
tended over sixty days. 
Kk 
