ent interest was going on, but was unable wholly to
understand the situation. After watching Gertie for a time and trying to
discover what she was doing, which was rendered difficult by her
tendency to turn away from him, in order to shield her injured finger,
he rushed over to the wire partition and made strenuous efforts to seize
Tiny with his hands and teeth. But although she continued close to the
partition and often crowded against it with face and hands flattened on
the wires, he was not able to get hold of her, and after a few vain
attempts he returned to his mate, and again with evident solicitousness
and the most troubled expression, watched her wringing her hands and
chewing or sucking at her injured finger. Shortly he again returned to
the partition and renewed his attempts to seize the young monkey. Thus
he went back and forth from one place of interest to the other several
times, but being unable to achieve anything at either point, he finally
gave up and returned to his breakfast on the floor of the cage.

I report this incident fully because the behavior of Jimmie was in
marked contrast with the usual behavior of the monkeys. Selfishness
seemed everywhere dominant, while clear indications of sympathetic
emotions were rare indeed. The above is undoubtedly the best evidence of
anything altruistic that I obtained.

It is possible that Tiny's action was retaliatory, but although it is
practically certain that either Gertie or Jimmie inflicted the wound on
her finger, I of course cannot be sure that the spirit of revenge
stirred her to punish Gertie so severely. Jimmie's part in the whole
affair is, however, perfectly intelligible from our human point of view,
and there seems no reason to doubt that he did experience something like
a feeling of sympathy with his mate, coupled with a feeling of
resentment or anger against Tiny.

VI

HISTORICAL AND CRITICAL DISCUSSION OF IDEATIONAL BEHAVIOR IN MONKEYS AND
APES

It is my purpose in this section to indicate the relations of my work on
monkeys and apes to that of other investigators. Although throughout the
report I have used freely the psychological terms idea and ideation, it
has been my aim to describe the behavior of my animals rather than to
interpret it or speculate concerning its accompaniments. Certain acts I
have designated as ideational simply because they seemed to exhibit the
essential features of what we call ideational behavior in man. Furt