1899] ORIGIN OF AUSTRALIAN FLORA 277 
Tasmania (Eocene), not met with earlier than the Pliocene age. Mr. 
Wallace, it will be observed, adopts the conventional notions based on 
present distribution to which objection has already been made, On this 
view, if an Australian genus or species has the Indo-Malayan facies 
and is found outside Australia, or is closely related to extra-Australian 
forms, it must have migrated into its present habitat; but the palpable 
errors into which Mr. Wallace has been led while formulating what he 
believes to be the true explanation of the case, may perhaps lead us to 
suspect that there is something wrong in the inference from present 
distribution whereupon his views are founded. 
Professor Tate’s conclusions are also based upon notions as to 
present distribution. He considers the Australian flora to be composed 
of two elements, an endemic and an immigrant. The endemic flora is 
of three kinds: Euronotian in the south and east, Autochthonian 
in the south-west, and Eremian in the desert. The immigrant flora 
has two constituents—an Oriental, dominant in the littoral tracts, but 
mixed there with typical Australian genera, and an Andean, restricted 
for the most part to the highlands of New South Wales, Victoria and 
Tasmania, and with this he includes north temperate forms, that is 
species characteristic of north temperate regions. The Autochthonian 
element was dismembered in Cretaceous times, and except for possible 
inter-communication with the Euronotian via the present Eremian region 
during the period of tertiary submergence, and perhaps, too, by means 
of land in the south now submerged, it has remained in a state of 
isolation. The Euronotian element was modified during early tertiary 
times by the irruption of a primitive cosmopolitan flora. The Andean 
element was introduced during a glacial period, and since then the 
Eremian flora has been developed from Autochthonian and Euronotian 
constituents, largely modified by an incursion of Indian types, while at 
the same time the Euronotian gained accessions from the Indo-Malayan 
province, although migrants have probably been received at all times 
since the specialisation of the flora of the Indo-Malayan province. 
It will be observed that Professor Tate is not content with making 
Australia a sort of botanical dumping ground during recent times, but 
that he ascribes a migrant character to the primitive tertiary flora as 
well. Is there sufficient justification for this? The primitive tertiary 
flora makes its appearance to all intents simultaneously in various 
parts of the earth, in North America, in Europe, at Perim, in Borneo, 
ete., as well as in Australia, and we have no evidence in any of these 
cases as to its origin in one of these localities, and of its migration 
into others. There seems also no conclusive evidence that the western 
part of Australia was absolutely isolated from the eastern half during 
earlier tertiary times, and it seems incredible, unless the climate of 
Western has greatly differed from that of Eastern Australia, that a flora 
which flourished over such a wide area as we have indicated, shall 
1 Tate, ‘‘ Inaugural Address,” p. 37. 
