274. ANIMAL INTELLIGENCE 
the 12th day, and the movements in which the head 
and face parts are concerned can be induced by 
electrical stimulation about this time. It is to be 
specially noted that these movements can be produced 
in the rabbit, experimentally, almost as soon as those of 
the fore-lmb—in fact, I question whether, in some 
cases at least, they are not excitable earlier and with 
greater facility, 7.¢e. with a weaker current. With the 
hind-legs the case is altogether different—in fact, my 
investigations would lead me to infer that the hind-legs 
are never related to the cortex in the same way as the 
fore-limbs. In no case have I been able to establish 
to my satisfaction the existence of a cortical centre for 
the hind-legs of the same nature (to put the matter 
cautiously) as those for the fore-limbs, head, face, ete. 
The relation between the early, and all but simultaneous, 
development of the cortical centre for the fore-limbs 
and head (and face) parts, and the physiological and 
psychic manifestations of the young rabbit afford one 
of the most beautiful and striking illustrations of cor- 
relation known to me. 
IV.—THE CAVY, OR GUINEA-PIG. 
THE cavy comes into the world able to take care of 
itself. It can, in a few hours, if not at once, run about 
quite well, eat, etc. It is at the set-out as far on in the 
path of development as a rabbit some days after its 
eyes are open, though in the end there is little difference 
between these two rodents physically or otherwise. 
Corresponding with this advanced physiological and 
psychic development, the cortex is, as I have shown, 
excitable at or soon after birth, so that here again there 
is rendered evident by experiment a close correlation 
of the kind considered throughout this paper. 
