FLORA OF TASMANIA. 
Myrtacea. 
Caprifoliaceae, absent in South Africa. 
Goodeniaceae, ditto. 
Stylidiese, ditto. 
Brunoniacese, ditto. 
Epacridese, ditto. 
My..j[ioviiie£e, ditto. 
Labiatse. 
Lentibularineae. 
PlantagineaB, absent in South 
Cupuliferje, ditto. 
Casuarinere, ditto. 
Coniferse. 
Xerotidese, ditto. 
Phylidrese, ditto. 
It is singular that there should be exactly the same number (sixteen) of Orders absent in each 
country ; of these, however, three Australian ones are confined to the south-eastern part of that 
continent, Magnoliacece, Monimiacea, and Caprifoliacea, which is in accordance with the facts I have 
elsewhere indicated, that the affinity between the Floras of South-west Australia and South Africa is 
very markedly greater than between that country and South-east Australia. 
I shall return to the consideration of the European genera of South Africa in the following 
section of this Essav. 
§11. 
On the European Features of the Australian Flora. 
In one respect this is by far the most difficult subject to treat of to the satisfaction of many 
persons interested in the study of the distribution of plants ; for situated as Australia is, at the anti- 
podes of Europe, the presence in it of many forms common to both, whether generic or specific, 
affords so strong an argument in favour of there being many centres of creation for each vegetable 
form, that I cannot expect the believers in that doctrine to follow me far. I have given my own 
reasons for dissenting from that view and inclining to the opposite one, that variation will account 
for change of species and genera; that the force of variation being a centrifugal one tends to diversity 
of forms and opposes reversion ; that Darwin's theory of natural selection accounts for the temporary 
stability of many forms we call species ; that the destruction of species by natural causes resolves 
species into genera, etc.; and that if we allow time enough, these several operations may have worked 
together and produced, out of what would otherwise be to us a homogeneous series of vegetable forms, 
a series broken up into varieties, species, and genera, all of unequal value, and of multiplied cross- 
affinities. I now pursue the subject of the European affinities of the Australian Flora in subjection 
to these views, not because I insist that they are right, nor because I expect to explain the facts by 
them, but because I conceive these hypotheses to be, in the present state of science, as legitimately 
tenable as those of absolute creations and multiplied centres, and far more suggestive to future 
inquirers of fresh ideas, that may be worked into one class of hypotheses or the other. 
The following is a list of the European genera and species hitherto discovered in Australia. I 
have indicated by As. those which, though found in Europe, are so scarce there, and so much more 
characteristic of Asia, that they cannot be considered as direct instances of affinity between Australia 
and Europe ; and by Trop. those genera that are only found in tropical or subtropical Australia. 
Those marked with an asterisk are possibly introduced. 
