slept, though it was an uneasy slumber,
disturbed by a feeling as though some one were holding a heavy black
quilt over his head, preventing him from breathing.

The feeling, sensation or dream--whatever it was--perhaps a
nightmare--became at last so real to Ned that he struggled himself into
wakefulness. With an effort he sat up, uttering an inarticulate cry.
To his surprise he was answered. Some one asked:

"What is the matter?"

"Who--who are you?" asked Ned quickly, trying to peer through the
darkness.

"This is Jacinto--your guide," was the soft answer. "I was walking
about camp and, hearing you murmuring, I came to your tent. Is
anything wrong?"

For a moment Ned did not answer. He listened and could tell by the
continued heavy and regular breathing of his chum that Tom was still
asleep.

"Are you in our tent?" asked Ned, at length:

"Yes," answered Jacinto. "I came in to see what was the matter with
you. Are you ill?"

"No, of course not," said Ned, a bit shortly. "I--I had a bad dream,
that was all. All right now."

"For that I am glad. Try to get all the sleep you can, for we must
start early to avoid the heat of the day," and there was the sound of
the guide leaving and arranging the folds of the mosquito net behind
him to keep out the night-flying insects.

Once more Ned composed himself to sleep, and this time successfully,
for he did not have any more unpleasant dreams. The quiet of the
jungle settled down over the camp, at least the comparative quiet of
the jungle, for there were always noises of some sort going on, from
the fall of some rotten tree limb to the scream or growl of a wild
beast, while, now and again, from the river came the pig-like grunts of
the alligators.

It was about two o'clock in the morning, as they ascertained later,
when the whole camp--white travelers and all--was suddenly awakened by
a wild scream. It seemed to come from one of the natives, who called
out a certain word ever and over again. To Tom and Ned it sounded like:

"Oshtoo! Oshtoo! Oshtoo!"

"What's the matter?" cried Professor Bumper.

"The vampires!" came the answering voice of Jacinto. "One of the
Indians has been attacked by a big vampire bat! Look out, every one!
It may be a raid by the dangerous creatures! Be careful!"

Notwithstanding this warning Ned stuck his head out of the tent. The
same instant he was aware of a dark enfolding shadow passing over him,
and, with a shudder o