There was no necessity for the last words, for both were running as fast as the nature of the ground would permit. The snake followed for a short distance, and then was lost to view.

But the boys kept right on, and it was not until both found themselves in a perfect labyrinth of undergrowth that they slackened their pace and finally came to a stop.

“Thank Heaven we have got away from him,” exclaimed Gus, puffing to catch his breath. “Huh! I can almost feel him coiling around my body!”

“So can I,” returned Oliver. “Of all things to meet I think a snake is the worst. I would just as lief encounter a tiger or a lion.”

“Let us get back at once,” said Gus; “I won’t feel safe until I am in the car, and when I am you won’t catch me leaving the train again until we arrive at Panama.”

“Just my sentiments,” rejoined Oliver. “Let us—”

He stopped short. “Where are we?”

Both suddenly gazed around them in alarm. Which way should they turn? Neither knew. They were lost in the forest!

CHAPTER XV.
AN ADVENTURE ON THE ISTHMUS.