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ON THE ORIGIN OF THE LOCAL FLORAS OF 
GREAT BRITAIN AND IRELAND. 
BY HARLAND COULTAS, 
LECTURER ON BOTANY AT THE CHARING CROSS HOSPITAL. 
T he botanical evidence from fossil plants proves irresistibly 
tbat tbe present vegetable creation bas been preceded 
by many others, — is continuous with them and the product of 
their labours, — is, in fact, only a fragmentary portion of that 
vegetable carpet with which nature has covered the earth 
during the successive periods of its geological history, and 
the pattern of which has been continually improving in beauty 
and variety. Fossil plants may be truly regarded as the re- 
mains of a system of vegetable life developed under external 
conditions, which are no longer the same in any part of the 
world. The calamite, lepidodendron, and other extinct forms 
of vegetation, on which our sun once shone, have at last dis- 
appeared for ever, as living agents, from the surface of our 
planet. They probably could not exist in the present w’orld ; 
but they helped to carry on the work of creation whilst they 
did. And the same remarks apply to the present living plants, 
all of which are contributing their part to the advance of 
nature, and are just as well and beautifully adapted to this 
stage of the world^s progress. 
The most important fact taught by fossil plants is that the 
organic and inorganic creation has slowly assumed its present 
appearance, and the evidence leads us to the unavoidable con- 
clusion that changes have taken place in the organization of 
plants by which their forms have been gradually adapted to 
the ever-changing landscape. The history of the origin of 
the local floras of the British isles is, therefore, intimately 
associated with the history of those physical changes which 
have brought about, slowly, their present geographical figure 
and position with reference to the continent of Em’ope. The 
history of these past changes, in so far as it tends to explain 
the present character and distribution of British plants, is a 
legitimate inquiry, fairly open to botanists and geologists. At 
present these changes are only imperfectly understood or 
traceable ; but every succeeding year adds to the store of facts 
