we take on the one side, the elephant, [7] hippopotamus, giraffe, bos
caffer, elan, certainly three, and probably five species of rhinoceros;
and on the American side, two tapirs, the guanaco, three deer, the
vicuna, peccari, capybara (after which we must choose from the monkeys
to complete the number), and then place these two groups alongside each
other, it is not easy to conceive ranks more disproportionate in size.
After the above facts, we are compelled to conclude, against anterior
probability, [8] that among the mammalia there exists no close relation
between the bulk of the species, and the _quantity_ of the vegetation,
in the countries which they inhabit.
With regard to the number of large quadrupeds, there certainly exists
no quarter of the globe which will bear comparison with Southern
Africa. After the different statements which have been given, the
extremely desert character of that region will not be disputed. In the
European division of the world, we must look back to the tertiary
epochs, to find a condition of things among the mammalia, resembling
that now existing at the Cape of Good Hope. Those tertiary epochs,
which we are apt to consider as abounding to an astonishing degree with
large animals, because we find the remains of many ages accumulated at
certain spots, could hardly boast of more large quadrupeds than
Southern Africa does at present. If we speculate on the condition of
the vegetation during these epochs we are at least bound so far to
consider existing analogies, as not to urge as absolutely necessary a
luxuriant vegetation, when we see a state of things so totally
different at the Cape of Good Hope.
We know [9] that the extreme regions of North America, many degrees
beyond the limit where the ground at the depth of a few feet remains
perpetually congealed, are covered by forests of large and tall trees.
In a like manner, in Siberia, we have woods of birch, fir, aspen, and
larch, growing in a latitude [10] (64 degs.) where the mean temperature
of the air falls below the freezing point, and where the earth is so
completely frozen, that the carcass of an animal embedded in it is
perfectly preserved. With these facts we must grant, as far as
_quantity alone_ of vegetation is concerned, that the great quadrupeds
of the later tertiary epochs might, in most parts of Northern Europe
and Asia, have lived on the spots where their remains are now found. I
do not here speak of the kind of vegetation necessary for their
support; because, as there is evidence of physical changes, and as the
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