hstanding the fact of
their extending to the snow-line on some of the Andean Mountains of
Chili, where several species of the Hedgehog Cactus were found by
Humboldt on the summit of rocks whose bases were planted in snow. In
California, in Mexico and Texas, in the provinces of Central and South
America, as far south as Chili, and in many of the islands contiguous to
the mainland, the Cactus family has become established wherever warmth
and drought, such as its members delight in, allowed them to get
established. In many of the coast lands, they occur in very large
numbers, forming forests of strange aspect, and giving to the landscape
a weird, picturesque appearance. Humboldt, in his "Views of Nature,"
says: "There is hardly any physiognomical character of exotic vegetation
that produces a more singular and ineffaceable impression on the mind of
the traveller than an arid plain, densely covered with columnar or
candelabra-like stems of Cactuses, similar to those near Cumana, New
Barcelona, Cora. and in the province of Jaen de Bracamoros." This
applies also to some of the small islands of the West Indies, the hills
or mountains of which are crowned with these curious-looking plants,
whose singular shapes are alone sufficient to remind the traveller that
he has reached an American coast; for these Cactuses are as peculiar a
feature of the New World as the Heaths are in the Old, or as Eucalypti
are in Australia.

Although the Cactus order is, in its distribution by Nature, limited to
the regions of America, yet it is now represented in various parts of
the Old World by plants which are apparently as wild and as much at home
as when in their native countries.

The Indian Figs are, perhaps, the most widely distributed of Cactuses in
the Old World-a circumstance due to their having been introduced for the
sake of their edible fruits, and more especially for the cultivation of
the cochineal insect. In various places along the shores of the
Mediterranean, and in South Africa, and even in Australia, the Opuntias
have become naturalised, and appear like aboriginal inhabitants. It is,
however, only in warm sunny regions that the naturalisation of these
plants is possible.

From these facts, we are able to form some general idea of the
conditions suitable for Cactuses when cultivated in our greenhouses;
for, although we seldom have, or care to have, any but diminutive
specimens of many of these plants as compared with their appe