ngth was failing more and more
daily, and although I was suffering no actual pain, yet the weakness was
simply appalling. It was all I could do to stand up on my legs. What was
worse for me was that my head was still in good working order, and I
fully realised our position all the time.

The country we were travelling over was fairly hilly, up and down most of
the time, over no great elevations. We passed two large tributaries of
the main stream we had found before, and a number of minor ones. The
main stream was strewn with fallen trees, and was not navigable during
the dry season. The erosion of the banks by the water had caused so many
trees to fall down across it that no canoe could possibly go through.

I noticed in one or two places along the river traces of human beings
having been there some years before.

In the afternoon we again wasted much energy in knocking down two
palm-trees on the summit of which were great bunches of _coco do matto_.
Again we had a bitter disappointment. One after the other we split the
nuts open, but they merely contained water inside shells that were much
harder to crack than wood. My craving for food was such that in despair I
took two or three _sauba_ ants and proceeded to eat them. When I ground
them under my teeth their taste was so acidly bitter that it made me
quite ill. Not only that, but one _sauba_ bit my tongue so badly that it
swelled up to a great size, and remained like that for several days. The
entire genus of the Sauba (_Oecodonia cephalotes_) ant is typical of
tropical South America. The largest Sauba is about an inch long, and
possesses powerful scissor-like clippers, with which it can destroy any
material, such as leather, cloth, paper or leaves, in a very short time.
Their method of work is to cut up everything into circles. I remember one
day dropping on the ground a pair of thick gloves. When I went to pick
them up I found them reduced to a heap of innumerable little discs--each
as large as a sixpenny coin. It is with those powerful clippers that the
Saubas, having climbed in swarms up a tree, proceed to despoil it of its
foliage. The work is done in a systematic way, each ant quickly severing
one leaf and carrying it down, banner-like, vertically above its head,
tightly held between its strong mandibles.

It is this habit of the Saubas which has brought upon them the Brazilian
name of _Carregadores_, or carriers. One sees everywhere in that country
long proce