PRESIDENTIAL ADDRESS. 563 
study of the Earth’s crust that we must look, rather than to the exigencies of 
botanists and zoologists, for its final solution. 
But the hypothesis of an Antarctic Land-Connection has been held open to 
doubt in various quarters. As Sir Wm. Thiselton Dyer has recently pointed out, 
Darwin himself dissented, though regretfully, from the sinking of imaginary 
continents in a quite reckless manner, and from the construction of land-bridges 
in every convenient direction. From the geological side Dana laid down the 
positive proposition that the Continents and Oceans had their general outline and 
form defined in earliest time, Sir John Murray, whose recent death we so deeply 
deplore, was an undeniable authority as to the Ocean-floor. He wrote quite 
recently with regard to Gondwana-land, that ‘the study of Ocean-depths and 
Ocean-deposits does not seem in any way to support the view that continental 
land has disappeared beneath the floor of the Ocean in the manner indicated.’ 
He suggested that the present distribution of organisms is better interpreted 
by the North Polar theory of origin. The ‘continuous current of vegetation ’ 
southward at the present time was recognised by Hooker himself, and definite 
streams of northern forms have been traced by him extending even to Australia 
and Tasmania. This might account for much in present-day distribution ; though 
“it seems doubtful whether it would fully explain the extraordinary distribution 
of Antarctic Plants. The problem must for the present remain an open one. 
This whole question, however, has a connection with the still wider difficulty 
of the existence within the Polar area of ancient Floras. In the north the 
fossils are even of sub-tropical character. Coal has been found in lands with a 
five months’ night. How did such plants fare if the seasonal conditions were at 
all like the present? To explain this it would be a physiological necessity to 
assume either an entirely different climatal condition in those regions from that 
of the present time; or, as has been suggested, some shifting or creeping of the 
Earth’s crust itself. These are, however, questions which we cannot undertake 
to discuss with effect in the Botanical Section. We must not do more than 
recognise that an unsolved difficulty exists. 
We pass now from Hooker’s great work to the last of the classical series, viz., 
the ‘Flora Australiensis’ of Bentham and Baron Ferdinand von Miller. It is 
embodied in seven volumes, and was completed in 1878. Bentham, while assent- 
ing in his ‘concluding preface’ to the principles laid down by Hooker in the 
Tasmanian Flora, recognised as the chief component part of the present Flora 
of Australia the indigenous genera and species, originated or differentiated in 
Australia, which never spread far out of it. Secondly, an Indo-Australian Flora 
showing an ancient connection between Australia and the lands lying to the 
north. It is represented especially in tropical and sub-tropical East Queens- 
land. Then there is the Mountain Flora common to New Zealand, and extend- 
ing generally to the southern extra-tropical and mountain regions, while other 
constituents are ubiquitous maritime plants, and those which have been intro- 
duced since the European colonisation. But the most remarkable, as they are 
the least easily explained, are some few plants identical with species from North 
and West America, and from the Mediterranean. They are stated to be chiefly 
annuals, or herbaceous or shrubby plants; free-seeders; while their seeds long 
retain the power of germination. This may perhaps give the clue to this curious 
conundrum of distribution. 
It has been fortunate that the duty of working out this remarkable Flora 
should have fallen into the hands of such masters as Robert Brown, Sir Joseph 
Hooker, and Bentham. The foundations were thus surely laid. The further 
progress of knowledge has been carried on by the late Baron Ferdinand von 
Miller, and it may be confidently left in the hands of others who are still with 
us. The completion of the task of observing and recording may still be far 
ahead. But I may be pardoned if I utter a word of anticipatory warning. 
There is at the present time a risk that the mere work of tabulating and defining 
the species in a given country may be regarded as the only duty of a Government 
Botanist ; that, whenever this is completed, his occupation will be gone. Some 
such erroneous idea, together with a short-sighted economy, is the probable 
explanation of the fact that certain positions hitherto held by professional 
botanists have recently been converted into positions to be held by agriculturists. 
Tn the countries where this has happened (and I refer to no part of Australasia) 
the vegetation had been very adequately, though not yet exhaustively, worked, as 
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