Quotation from: The Beasts of Tarzan

Written by: Edgar Rice Burroughs

When all were in place it was discovered that two of the apes of
Akut were missing, and though both the king ape and Tarzan called
to them for the better part of an hour, there was no response, and
finally the boat put off without them. As it happened that the
two missing ones were the very same who had evinced the least desire
to accompany the expedition from the island, and had suffered the
most from fright during the voyage, Tarzan was quite sure that they
had absented themselves purposely rather than again enter the canoe.