s from the Alderneys or the Highland breed.
I was led to this from having once seen a black rhinoceros with a horn
bent downward like that of the kuabaoba, and also because the animals
of the two great varieties differ very much in appearance at different
stages of their growth. I find, however, that Dr. Smith, the best
judge in these matters, is quite decided as to the propriety of the
subdivision into three or four species. For common readers, it is
sufficient to remember that there are two well-defined species, that
differ entirely in appearance and food. The absence of both these
rhinoceroses among the reticulated rivers in the central valley may
easily be accounted for, they would be such an easy prey to the natives
in their canoes at the periods of inundation; but one can not so readily
account for the total absence of the giraffe and ostrich on the high
open lands of the Batoka, north of the Zambesi, unless we give credence
to the native report which bounds the country still farther north by
another network of waters near Lake Shuia, and suppose that it also
prevented their progress southward. The Batoka have no name for the
giraffe or the ostrich in their language; yet, as the former exists in
considerable numbers in the angle formed by the Leeambye and Chobe, they
may have come from the north along the western ridge. The Chobe would
seem to have been too narrow to act as an obstacle to the giraffe,
supposing it to have come into that district from the south; but the
broad river into which that stream flows seems always to have presented
an impassable barrier to both the giraffe and the ostrich, though they
abound on its southern border, both in the Kalahari Desert and the
country of Mashona.

We passed through large tracts of Mopane country, and my men caught a
great many of the birds called Korwe ('Tockus erythrorhynchus') in their
breeding-places, which were in holes in the mopane-trees. On the 19th
we passed the nest of a korwe just ready for the female to enter; the
orifice was plastered on both sides, but a space was left of a heart
shape, and exactly the size of the bird's body. The hole in the tree
was in every case found to be prolonged some distance upward above the
opening, and thither the korwe always fled to escape being caught. In
another nest we found that one white egg, much like that of a pigeon,
was laid, and the bird dropped another when captured. She had four
besides in the ovarium. The first