BRITISH PLANTS: 
THEIR BIOLOGY AND ECOLOGY 
INTRODUCTION 
THE ENVIRONMENT—FUNDAMENTAL CONSIDERATIONS 
Tue study of plants in relation to their natural sur- 
roundings or environment is known as Plant Ecology 
(Gr. oikos, a home). 
Every plant which lives and succeeds in reproducing 
itself may be regarded, on the one hand, as an efficient 
machine, satisfactorily performing its various physio- 
logical functions; and, on the other, as an organism adapted 
to, or in equilibrium with, its environment. Otherwise 
it would perish and leave no descendants behind. Again, 
when we examine any association of plants living together 
under much the same conditions, a wonderful diversity 
of form, habit, and growth meets our eyes ; and, seeing 
that each plant in this association is a successful unit in 
the battle of life, we are driven to the conclusion that not 
only is it adapted to its environment, but that this 
adaptation is reached in many and various ways. 
These three considerations—namely, 
(1) That a successful plant is an efficient machine ; 
(2) That it is in equilibrium with its environment ; 
(3) That this adaptation is reached in many different 
ways 
—lie at the root of Plant Ecology, and form the basis upon 
which our knowledge of the vegetable population of the 
globe has been founded. 
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