nd eagerly
entering any box which happened to be open, in order to obtain the
reward of food.

The regular experimentation was undertaken on April 13, and the results
of the first series of trials with Julius are sharply contrasted with
those obtained with the monkeys in that fewer choices were necessary.
Instead of the expected ratio of right to wrong first choices, 1 to 2.5,
the orang utan gave a ratio of 1 to 1. An additional markedly different
result from that obtained with the monkeys is indicated below in the
total time required for a series of trials. As examples, the data for
the first, second, fifth, and tenth series are presented.

TIME FOR SERIES OF TRIALS

1st series 2nd series 5th series 10th series
Skirrl 35 min. 20 min. 14 min. 10 min.
Sobke 14 " 17 " 10 " 9 " (8th series)
Julius 12 " 11 " 14 " 9 "

It is also noteworthy that Julius in the presence of visitors or under
other unusual conditions worked steadily and well, whereas the monkeys,
and especially Sobke, tended to be distracted and often refused to work
at all.

Almost from the beginning of his work on problem l, Julius began to
develop the tendency to enter immediately the open door nearest the
starting point. In case the group of open doors lay to the right of the
middle of the apparatus, this method naturally yielded success; whereas
if the group included doors to the left of the middle, it resulted in
failure. Obviously it was a most unsatisfactory method, and although it
enabled him to make more right than wrong first choices, it prevented
him from increasing the number of right choices, and as table 1
indicates, it maintained the ratio of 1 right to .67 wrong first choices
for eight successive days.

On April 23 a break occurred in which the number of correct choices was
reduced from six to five. Julius worked very rapidly and with almost no
hesitation in choosing. My notes record "he seems to miss the point
wholly. It is doubtful whether the punishment is sufficiently severe."
At this time he was being punished by thirty seconds confinement in each
wrong box, the interval having been held fairly steadily from the first
series of experiments. On April 26 it was increased to sixty seconds, in
an effort to break him of the habit of choosing the "nearest" door. But
he became extremely restless under the longer confinement and tried his
best to raise the entr