ion.

During the night in less than one hour we caught two large _jahu_, one
huge _pacu_ (_Prochilodus argentius_), the latter shaped like a sole,
but of a much greater size, and with brilliant red patches on its body--a
most delicately-tasting fish to eat--and a number of large _trahira_
(_Machrodon trahira_), also called by the Brazilians _rubaffo_ because of
the noise they make in the water. Altogether over 200 lb. of fish were
got out of the water in less than sixty minutes.

We found many _jenipapeiros_ (or _genipapeiro_) trees, from the stewed
bark of which we made excellent tea. Its fruit was good to eat, and we
used it for making sweets.

During the night of July 19th the minimum temperature was 67 deg. F.

We started off gaily enough in the morning, passing first a great
boulder, 10 m. in diameter, sticking right out of the water; then an
island 200 m. long contained in a basin 500 m. wide. We left the
island--Ruby Island--which was 80 m. long, on our left, and went down a
channel with strong eddies and whirlpools. Looking back at the eastern
channel, we were glad we had not followed it, as it was extremely rocky.

[Illustration: A Fine Cataract on the Arinos-Juruena River.]

The river was contracting in narrow necks and expanding into large
basins, another of these being 450 m. broad. A strong rapid existed here,
owing to the barrier formed across the stream by a central island of rock
and other boulders. After that came a basin 700 m. wide, with three
islands--Teffe I., Nair I., Rock I.--in its western part. The central and
eastern passages were difficult owing to the quantity of rocks which
stood in the way, so we took the canoe down the channel from S.S.W. to
N.N.E., which was also extremely bad, and where we had to let her down
with the greatest care by means of ropes, the baggage having been
previously unloaded. Even then the canoe got filled with water. That
involved a great loss of time and waste of energy, so that we had to halt
longer than usual in the middle of the day.

Our halting place was most picturesque, situated on volcanic rocks of
great beauty, and overlooking a canal cut into the rocks, with strong and
foaming rapids from east to west. Strong eddies formed at the end of the
rapids.

After leaving the camp and negotiating the rapids, we came to an island
150 m. long--Magda Island--separated by a rocky narrow channel from
another island, 50 m. long, west of it.

After the last rapid