Fururr Borantst. 9 
for all these terms mean the same thine. Mixed up with this 
study of suitability is another problem of still @reater importance 
—‘ The Evolution of Plant Organs.” Darwin’s work on the *“ Origin 
of Species”’ was incomplete in one respect. He showed that if a 
more suitable variety were granted, this best variety would be 
chosen by Nature just as a gardener would select it, namely, by 
weeding out the others which were less suitable. Darwin did zo¢ 
show how the variety arose. 
In some cases the climate, by its own direct influence, produces 
that variety which is the most fitted to itself. It is true that this has 
only been proved in a few cases, but the theory may be entirely 
general. A simple instance will make this clear. The first time that 
a man rows in a boat he discovers that he blisters the hand at the 
root of his fingers; this painful result is followed by the formation 
of hard skin pads at the place, and with these he can row without 
pain. It is only required to suppose that these pads or hardnesses 
should be inherited to see how, in this instance, the direct action 
of the surroundings produces the variety best suited to resist them. 
To put it more simply, there are two distinct branches of botany, 
the one “/Vhy plants have certain organs and arrangements,” 
and the other, ‘“ Hozw they produced such organs.” It is obvious, 
if we wish to study these questions, it is quite essential that 
we should have a thorough knowledge of the climate, habitat, 
or environment of every plant, and that is exactly what 
we do not possess. The late Dr Gilchrist had a very clear 
idea of this problem. I quote his exact words: ‘It is very diffi- 
cult, from its extreme complexity, involving a knowledge of the 
plant’s relation to whatever can modify its growth, to the soil on 
which it grows, to the air which it breathes, to the sun which gives 
it light, to the rain, dew, or snow which afford it moisture.” I do 
not know when these words were spoken, but it shows that Dr 
Gilchrist anticipated the very newest botanical ideas. 
Perhaps the best method is to take the various organs of the 
plant in detail, and to try and show zy they have their present 
shape, and perhaps, in some cases, “ow these have been evolved. 
Flowers are the more important organs, and it is on this 
account that in the Flora of Dumfriesshire I have included insect 
visitors where possible, these bemg essential parts of a flower’s 
environment. I found it impossible in one season to investigate 
more than six species thoroughly, on account of the unfortunate 
