THE PSYCHIC DEVELOPMENT OF YOUNG ANIMALS 171 
developed much faster psychically than St Bernards, 
and they also mature earlier, physically and otherwise, 
a remark that applies to the smaller breeds of dogs 
generally. 
They sooner show, especially in movements, a great 
superiority, which strengthens the opinion I have 
expressed, that, among animals, the degree of advance- 
ment in co-ordinated movements is a fairly good guide 
to psychic progress at early periods. 
WHAT REMAINS TO BE DONE—I am now anxious, 
as all my work has been done on pure-bred dogs, to 
study a litter of mongrels. 
It has been thought well to confine this paper to the 
study of the early development of dogs. 
I can see the desirability of supplementing this paper 
by the account of some one dog from birth to maturity, 
and possibly I may be able to do this. 
I purpose following this paper by another similar 
one on the development of other animals in the earlier 
periods of existence, considerable material for which 
has already been accumulated, so that I hope in time 
to get the facts in such form, that broad and sound 
conclusions as to development of young animals may be 
drawn. 
As the dog, after the monkeys and apes, more closely 
resembles man psychically than any other animal, it 
seems to me that it would be very profitable to attempt 
a comparison of the development of the young dog 
and the infant. But this task must also be deferred. 
For various reasons I have not referred in detail to 
the fragmentary work of others, chiefly because the 
original papers are not, in most cases, accessible to me 
now, and because prolonged discussions and com- 
parisons with their results would add to the length of 
an already long paper. I present my observations with 
such conclusions as I have tried to draw cautiously, 
