ing their roots buried far beneath the soil,
feel little the effects of the scorching sun. The number of these which
have tuberous roots is very great; and their structure is intended to
supply nutriment and moisture, when, during the long droughts, they
can be obtained nowhere else. Here we have an example of a plant, not
generally tuber-bearing, becoming so under circumstances where that
appendage is necessary to act as a reservoir for preserving its life;
and the same thing occurs in Angola to a species of grape-bearing vine,
which is so furnished for the same purpose. The plant to which I
at present refer is one of the cucurbitaceae, which bears a small,
scarlet-colored, eatable cucumber. Another plant, named Leroshua, is
a blessing to the inhabitants of the Desert. We see a small plant with
linear leaves, and a stalk not thicker than a crow's quill; on digging
down a foot or eighteen inches beneath, we come to a tuber, often as
large as the head of a young child; when the rind is removed, we find it
to be a mass of cellular tissue, filled with fluid much like that in a
young turnip. Owing to the depth beneath the soil at which it is found,
it is generally deliciously cool and refreshing. Another kind, named
Mokuri, is seen in other parts of the country, where long-continued
heat parches the soil. This plant is an herbaceous creeper, and deposits
under ground a number of tubers, some as large as a man's head, at spots
in a circle a yard or more, horizontally, from the stem. The natives
strike the ground on the circumference of the circle with stones, till,
by hearing a difference of sound, they know the water-bearing tuber to
be beneath. They then dig down a foot or so, and find it.

But the most surprising plant of the Desert is the "Kengwe or Keme"
('Cucumis caffer'), the watermelon. In years when more than the usual
quantity of rain falls, vast tracts of the country are literally covered
with these melons; this was the case annually when the fall of rain was
greater than it is now, and the Bakwains sent trading parties every year
to the lake. It happens commonly once every ten or eleven years, and
for the last three times its occurrence has coincided with an
extraordinarily wet season. Then animals of every sort and name,
including man, rejoice in the rich supply. The elephant, true lord of
the forest, revels in this fruit, and so do the different species of
rhinoceros, although naturally so diverse in their choic