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In addition to the above it is well to note that the appendices in the narrative volumes of the voyages of discovery and the inland exploring expeditions give many botanical details.

Baron von Mueller's "Census of Australian Plants, 1889" enumerates 8,839 Australian plants which, after critical revision, he admits as well-founded and established species. These lie grouped into 156 natural orders comprising 1,409 genera. Additions since made to this flora have perhaps raised the total number of species to about 9,000, but in discussing the characteristics of Australian vegetation these additions raise no material issues.

Briefly stated, the Australian flora is constituted of three elements, viz.—(1) The autochthonous or original Australian vegetation more or less spread over the whole continent, but with many of its species very localized. (2) An immigrant element, mainly Oriental, which dominates the tropical northern coasts, but does not obliterate the distinctively Australian characteristics of those coastal regions. (3) An alpine or cold region flora, also immigrant, and typical of the Andes Mountains of South America. This element survives now only on the highest mountains of Tasmania, Victoria, and New South Wales.

For the ancestral types of each of these elements search must be made far back in the rocks of the geological record. The two immigrant floras are descendants of families of relatively recent date and are as yet comparatively little modified. The autochthonous element, on the contrary, is descended from families so ancient that many of the types have become extinct in other parts of the world, and but for their survival in Australia many genera would to-day be known only by their fossil forms. Some fifty species found fossil in Australia still survive in the world's flora, but of this number no fewer than seventeen survive only in the Australian region. They belong to the genera Byblis, Casuarina, Cephalotus, Santalum, Nuytsia, Polyompholyx, Persoonia, Grevillea, Hakea, Lomatia, Banksia, Dryandra, Callicoma, Ceratopetalum, Boronia, Eucalyptus, and Phylloglossum. All of these, except Persoonia, Hakea, and Boronia, occur as fossils in Europe, some of them as far north as Greenland and Spitzbergen. Of the other species (or species very closely akin to them), seven live in North America and two in Brazil. Sixteen range among East Indian islands, three are in Japan, one in the African island of Bourbon, one in the Himalayas, one in Syria, three in Europe, and two in New Zealand. Among the forms of plant life of the ancient ages which still survive, but which now have forsaken Australia, are Sequoias (pines), indistinguishable from the giant pine of California and the lumber wood which America exports to Australia from Oregon in such immense quantities. The "cedar of Lebanon" and the oak and the beech-trees also once had an Australian home. Such facts suggest that in ancient days the world's climatic conditions favoured a far wider range of specific plant life than now obtains, or that the plants were better able to struggle in the battle for existence. This is still better seen if the geological ages are traced still farther back. New Zealand, for instance, shows very little affinity with Australia during the Tertiary period, but in the Mesozoic period she had in common with Australia certain forms which still survive as closely-allied species among living floras. The Gingko pine of China and Japan, the Araucaria or "Norfolk Island pine" and the Dammara or "Kauri" pine are