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THE ESSEX NATURALIST.
settled countries bear the mark of the effect of the action of
man and his crops and herds, and would not revert to the original
state even if such action were now removed.
He then proceeded to show, by two examples which had come
under his own observation, how much had been lost to science
by the want of care for the preservation of the original floras of
St. Helena and the Bermudas.
As regards our own islands, although a large proportion of
our flora is certainly the result of post-glacial immigration from
the Continent, it is now recognised that various types of endemic
species were probaby associated with specially favoured
localities remaining unglaciated which served them as homes
of refuge and this gives rise to some very interesting problems
both geological and botanical.
Another proof that our British flora is still a fertile object
of study and worthy of preservation on that account is that
the more it is intensively studied the more extensive it is found
to be, new species even now being constantly added to the list,
as for example a new Brassica recently found on Lundy Island,
and the greater the number of minor differences brought to light
within the species. These facts also give rise to most interesting
problems of distribution of forms within our islands and their
relations with continental forms.
From the scientific point of view there is no doubt that native
floras are well worth preserving. In this connection local
floristic lists and vegetational surveys of limited areas are of
great importance and local Natural History Societies can give
much help in these directions.
On the question whether it is ever allowable to introduce
plants into an area where they are not now nor ever have been
found, as advocated by some people with the best intentions,
Dr. Rendle said he saw no objection to the re-establishment of a
species where it has been destroyed by human action provided
it was done with the utmost care and an accurate record kept.
But the introduction of species into any presumably suitable
places and the broadcast scattering of seed are to be strongly
deprecated while the introduction of, say, alien alpines on a
British mountain is thoroughly reprehensible.
As regards the best methods of ensuring the preservation of
our native flora Dr. Rendle referred to the work of a number of