FLORA OF TASMANIA. 
§ 2. 
Estimate of the Australian Flora, and some General Remarks on the Classes and Orders, 
their Numbers, Distribution, and Affinity. 
I estimate the Flowering Plants known to be indigenous to Australia* at about 8,000 species, a 
number which will not in all probability be much increased by further investigations, because it 
includes upwards of 500 of which I have seen no specimens, and a considerable proportion of which 
will no doubt prove to be founded on error, and it includes a much larger number which I have 
reason to believe will prove to be varieties,t when more of their forms are collected, or themselves 
more carefully studied. 
About ten years ago (1849), Brown, in the appendix to Sturt's Voyage, estimated the Austra- 
lian Flora at something under 7,000 species ; since which period 1,000 species have not been added, 
although the explored area has been greatly enlarged, both by surveys of the tropical coasts, and 
inland journeys made to the north of the Tropic of Capricorn, and especially by the investigations 
of Dr. Mueller, during his adventurous explorings of the Australian Alps, and of the northern and 
eastern parts. Dr. Mueller % himself, who has personally explored more of the continent than any 
other botanist, except the late Allan Cunningham, considers that the total Flora, including the 
undiscovered species, Phcenogamic and Cryptogamic (exclusive of the minute Fungi and fresh-water 
Algce), cannot exceed 10,000 species. Cryptogamic plants are known to be extremely rare in Australia 
as compared with Phamogamic ; nevertheless, as they already amount to fully 2,000 discovered spe- 
cies^ I suspect that Dr. Mueller's estimate is more probably too low than too high, and that we may 
assume 9,000-10,000 flowering plants as an approximation to the number that will eventually be 
found to be indigenous to Australia. \\ 
Considering that the vegetation of Australia is confined to a belt of more or less fertile land 
surrounding an arid desert, which occupies perhaps two-thirds of its total area, and that the tropical 
region is an extremely poor one in plants, this Flora must be considered as very large. And if the 
tropical Flora is excluded, and the temperate alone compared numerically with that of Europe for 
instance, the very varied nature of the Australian vegetation will appear all the more remarkable. 
Thus the superficies clothed with any considerable number of species in extra-tropical Australia, is 
probably not equal to one-fifth of the similarly clothed area of Europe, which, though so much more 
varied in all its physical features, contains only 9,648** species, according to Nyman's list, and this 
* Except when otherwise stated, t include under the general term Australia. 
f Dr. Mueller's valuable notes upon my 'Tasn td in the Supplement, show 
how very much is to he done in the reduction of species founded on herbarium specimens, even when these are 
unusually copious and good. 
X Journal of the Linnrean Society, Botany, vol. ii. p. 141. 
§ In Tasmania alone there are Ferns and allies, 70 ; Mosses and Hepaticns, 386 ; Alga?, 315 ; Lichens, ahout 
100 ; Fungi, 275. And I cannot doubt but that this number will be doubled by future discoverers. 
II I need hardly remark, that the as to what amount and con- 
stancy of difference between many forms of plants should constitute a species, renders all such comparisons vague ; 
and I may add that no two or more botanists can ascertain the comparative value of their opinions except they have 
exactly the same materials to work with. It is too often forgotten that in the sciences of observation what an called 
negative facts and evidence are worthless as compared with positive. 
** Nyman, Sylloge Florae Europae. 
