ant
are used by the natives of the Amazon for a variety of purposes,
such as constructing inside walls, making boxes and baskets, etc.
_R. vinifera_, the Bamboo palm, is similarly used by the Africans,
who also make a very pliable cloth of the undeveloped leaves. Palm
wine is one of the products of the genus.

367. RAVENALA MADAGASCARIENSIS.--This plant is called the Traveler's
tree, probably on account of the water which is stored up in the
large cup-like sheaths of the leaf-stalks, and which is sought for
by travelers to allay their thirst. The broad leaves are used in
Madagascar as thatch to cover their houses. The seeds are edible,
and the blue, pulpy aril surrounding them yields an essential oil.

368. RHAPIS FLABELLIFORMIS.--The ground rattan palm. This is supposed
to yield the walking-canes known as rattan, which is doubted. It
is a native of southern China, and is also found in Japan, where
it is known by the name of Kwanwortsik.

369. RHIZOPHORA MANGLE.--This plant is known as the mangrove, possibly
because no man can live in the swampy groves that are covered with
it in tropical countries. The seeds germinate, or form roots
before they quit the parent tree, and drop into the mud as young
trees. The old plants send out aerial roots into the water, upon
which the mollusca adhere, and as the tide recedes they are seen
clinging to the shoots, verifying the statements of old travelers
that they had seen oysters growing on trees. All parts of this
tree contain tannin. The bark yields dyes, and in the West Indies
the leaves are used for poulticing wounds. The fruit is edible; a
coarse, brittle salt is extracted from the roots, and in the
Philippines the bark is used as a febrifuge.

370. ROTTLERA TINCTORIA.--This plant belongs to the order
_Euphorbiaceae_, and reaches the size of a small tree in the Indian
Archipelago and southern Australia. From the surface of the
trilobed capsules of this plant, which are about the size of peas,
a red, mealy powder is obtained, well known in India as kamala,
and which is used by Hindoo silk-dyers, who obtain from it a deep,
bright, durable orange or flame color of great beauty. This is
obtained by boiling the powder in a solution of carbonate of soda.
When the capsules are ripe the red