On the Gapo, or submerged lands, however, a considerable difference in
the vegetation appears. The palms are here often more numerous than in
other parts. This is the region where the cacao-tree and prickly
sarsaparilla grow. Here the underwood is less dense, the sipos retiring
to weave their tracery among the upper branches alone. Though during
the dry season the vegetation springs up with wonderful rapidity, it is
swept away by the next overflow.
Here the lovely orchis tribe adorn the gloomy shades with their
brilliant flowers. Among the most beautiful is the oncidium, of a
yellow hue, often seen--apparently suspended in air between the stems of
two trees--shining in the gloom, as if its petals were of gold. In
reality it grows at the end of a wire-like stalk a yard and a half long,
springing from a cluster of thick leaves on the bark of a tree; others
have white and spotted blossoms, growing sometimes on rotten logs
floating on the water, or on moss and decayed bark just above it. Still
more magnificent is the Flor de Santa Ana, of a brilliant purple colour,
emitting a most delicious odour.
Peculiar and strange is this region of the Gapo. When the waters are at
their height it can be traversed in all directions. The trees which
grow on it, and the animals which here have their abodes, appear to
differ from those of other districts.
Let us accompany the naturalist Wallace, in his canoe, through a
district of this description; now forcing our way under branches and
among dense bushes, till we get into a part where the trees are loftier
and a deep gloom prevails. Here the lowest branches of the trees are
level with the surface of the water, many of them putting forth flowers.
As we proceed we sometimes come to a grove of small palms, the leaves
being now only a few feet above us. Among them is the maraja, bearing
bunches of agreeable fruit, which, as we pass, the Indians cut off with
their long knives. Sometimes the rustling of leaves overhead tells us
that monkeys are near, and we soon see them peeping down from among the
thick foliage, and then bounding rapidly away. Presently we come out
into the sunshine, on a lake filled with lilies and beautiful
water-plants, little bladder-worts, and the bright blue flowers and
curious leaves with swollen stalks of the pontederias. Again we are in
the gloom of the forest, among the lofty cylindrical trunks rising like
columns out of the deep water; and now there is a splash of fruit
falling around us, announcing that birds are feeding overhead, and we
discover a flock of parrakeets, or bright blue chatterers, or the lovely
pompadour, with its delicate white wings and claret-coloured plumage.
Now, with a whir, a trogon on the wing seizes the fruit, or some clumsy
toucan makes the branches shake as he alights above our heads.
This region, as might be supposed, is not destitute of inhabitants.
Several tribes of Indians dwell within it all the year round. Among
them are the Purupurus and Muras tribes, who, spending most of their
time in their canoes, in the dry season build small huts on its sandy
shores; and when the waters overflow it, form rafts, which they secure
between the trees, sleeping in rude huts suspended from the stems over
the deep water, and lighting their fires on masses of mud placed on
their floating homes. They subsist entirely on fish, turtle, and
manatee.
Several species of trogons are peculiar to this submerged region. The
curious black umbrella-bird is entirely confined to it, as is also the
little bristle-tailed manakin. Several monkeys visit it during the wet
season, for the sake of its peculiar fruits; and here the scarlet-faced
urikari has its home.
For miles and miles together the native traverses this region in his
canoe, passing through small streams, lakes, and swamps, scraping the
tree trunks, and stooping to pass between the leaves of the prickly
palms, now level with the water--though raised on stems forty feet
high--while everywhere round him stretches out an illimitable waste of
waters, but all covered with the lofty virgin forest. In this trackless
maze, by slight indications of broken twigs or scraped bark, he finds
his way with unerring certainty.
"This curious region," says Wallace, "extends from a little above
Santarem to the confines of Peru, a distance of about 1700 miles; and
varies in width on each side of the river from one to ten or twenty
miles."