so had all of them--a very singular species of
ants' nests of a yellowish brown colour. The ants themselves were of a
beautiful emerald green. They were the _Formica spinicollis_. These
nests were composed of a soft cotton-down, which the ants had collected
from a species of _Melastoma_, a handsome shrub found growing in these
regions; and this down Guapo knew to be the best for blood-stopping.

Even Don Pablo had heard of its being used by the Indians for this
purpose, and knew it by the name of "_yesca de hormigas_," or
"touch-wood of ants." He had heard, moreover, that it was far superior
even to the ants' nests of Cayenne, which form an article of commerce
and are highly prized in the hospitals of Europe. Guapo, therefore, ran
off and robbed the green ants of their nests, and speedily returned
with the full of his hands of the soft "yesca." This was applied to the
wounds, and in a few minutes the bleeding was effectually stopped, and
Leon, although still suffering pain, had now only to be patient and get
well.

Strange to say, another incident occurred that very evening, which
taught our party a further lesson of the danger of taking to the water
without knowing more of its inhabitants. Just as they had finished
supper, and were seated in front of their new house, the mule, that had
been let loose, stepped into the river to drink and cool its flanks. It
was standing in the water, which came up to its belly, and, having
finished its drink, was quietly gazing around it. All at once, it was
observed to give a violent plunge, and make with hot haste for the bank.
It snorted and looked terrified, while its red nostrils were wide open,
and its eyes appeared as if they would start from their sockets. At
length it reached the bank, and, staggering forward, rolled over in the
sand, as if it was going to die!

What could all this mean? Had it, too, been attacked by the "caribes?"
No; that was not likely, as the bite of these creatures upon the hard
shanks of the mule could not have produced such an effect. They might
have frightened it, but they could not have thrown it into "fits"--for
it was evidently in some sort of a fit at that moment.

It might have been a puzzle to our party not easily solved, had Guapo
not been upon the spot. But Guapo had witnessed such an incident before.
Just before the mule gave the first plunge Guapo's eyes had been
wandering in that direction. He had noticed an odd-looking form glide
near th