Physical geography. By Mary Somerville ...

360 PHYSICAL GEOGRAPHY. CHAP. XXVI.
when the seeds of these fig-trees are deposited by birds on the ironbark-tree, or euacalyptus resinifera, that they vegetate and enclose
the trunk of the tree entirely with their roots, whence they send off
enormous lateral branches, which so completely envelop the tree,
that at last its top alone is visible in the centre of the fig-tree, at
the height of 70 or 80 feet. The Pandanus genus flourishes within
the influence of the sea-air. There are only six species of palms,
equally local in their habitations as elsewhere, not one of which
grows on the west side of the continent. The Araucaria excelsa,
or Norfolk Island pine, produces the best timber of any tree in this
part of Australia: it, or others of the same genus, extends from the
parallel of 29~ on the east coast towards the equator, and grows
over an area of 900 square miles, including New Norfolk, New Caledonia, and other islands, some of which have no other timber-tree:
they are supposed to exist only within the influence of the sea.
The Asphodelese abound and extend to the southern extremity of
Van Diemen's Land.
The south-western districts of Australia exhibit another focus of
vegetation, less rich in species than that of Port Jackson, but not
less peculiar. The kingia australis, or grass-tree, rises solitary on
the sandy plains, with bare blackened trunks as if scathed by lightning, occasioned by the fires of the natives, and tufts of long grassy
leaves at their extremities; Banksias, particularly the kind called
wild honeysuckle, are numerous; the Stylidium, whose blossoms are
even more irritable than the leaves of the sensitive mimosa, and
plants with dry, everlasting blossoms, characterize the flora of these
districts. The greater part of the southern vegetation vanishes on
the northern coasts of the continent, and what remains is mingled
with the cabbage-palm, various species of the nutmeg tribe, sandalwood, and other Malayan forms-a circumstance that may hereafter
be of importance to our colonists.
Orchicdee, chiefly terrestrial, are in great variety in the extra-tropical regions of Australia, and the grasses amount to one-fourth of
the monocotyledonous plants. Reeds of gigantic size form forests
in the marshes, and kangaroo grass covers the plains.
Beautiful and varied as the flora is, Australia is by no means luxuriant in vegetation. There is little appearance of verdure, the
foliage is poor, the forests often shadeless, and the grass thin but
in many valleys of the mountains, and even on some parts of the
plains, the vegetation is vigorous. It is not the least remarkable
circumstance in this extraordinary flora, that, with the exception of
a few berries, there is no edible fruit, grain, or vegetable indigenous
either in Australia or Van Diemen's Land.
The plants of Australia prevail in every part of Van Diemen's
Land; yet the coldness of the climate and the height of the rnoumtains pe'rmit genera of the northern hemisphere to be mixed with