monkey. It seemed bent over, as if it stooped toward the ground.

"Who are you?" called Mark suddenly.

For an instant the figure halted and then hurried on faster than
before, with a curious, shuffling walk. It was approaching the ship.

Somehow it struck Mark as if it was an uncanny being; an inhabitant of
some other world. Then he laughed at his half-fear, and started on a
run toward the dock.

"If it's some tramp trying to find a place to sleep he'd better not go
aboard the ship, he might do some damage," the boy thought.

He could hardly see the figure now as it had passed into the shadow
cast by the boat. He was about to summon the professor to make an
investigation, when Washington started going the search light which
was placed just over the door of the living cabin. It was kept there
as a sort of beacon light, as, near the island was a dangerous ledge
of rocks.

Then, in the blinding white glare from the big lantern as Washington
accidentally swung it toward the Mermaid, Mark beheld a strange sight.

The figure he had been watching stood out in bold relief. Though it
was shaped like a human being it was not like any person the boy had
ever seen. It seemed covered with a skin twice too large for it; a
skin, which, in spite of the clothes that concealed it, hung in folds
about the arms and legs, dropping pendent like from the neck like a
big garment, and flapping in the wind.