NATURAL SELECTION. XVil 
NATURAL SELECTION. 
The flora of a scattered group of islands is more 
interesting than that of a compact area of the same 
size. Comparative isolation reduces the risk of cross- 
fertilisation, and tends to give each species more 
scope to develop new characters in keeping with its 
environment. No part of botany is more interesting 
than the manner in which plants adapt themselves 
to their environment. One result which comes out 
with sufficient clearness from recent investigation is 
the great amount of variability there is in plants. 
Under moist conditions, a plant tends to develop 
hairiness, which protects the stomata from the 
entrance of water, thereby enabling the plant to 
thrive better than those not so protected. When 
this additional structure has developed, the plant is 
better able to surmount this peculiarity of climate. 
This characteristic developes healthier plants, which 
are consequently selected by Nature to an abundant 
erowth. This is natural selection. Darwin says :— 
“As many more individuals of each species are born 
than can possibly survive, and as consequently there 
is a frequent, recurring struggle for existence, it 
follows that any being, if it vary, however slightly, 
in any manner profitable to itself, under the complex 
and varying conditions of life will have a_ better 
chance of surviving, and thus be naturally selected. 
From the strong principle of inheritance, any selected 
variety will tend to propagate its new and modified 
form. This preservation of favourable individual 
