THE STRUGGLE FOR EXISTENCE 193 
differences were useful in the particular environment 
in which the plants existed, the individuals possessing 
them would soon oust those not so well equipped and 
occupy the area, victorious in the ‘‘Struggle for 
Existence.’’ It is to this Struggle, resulting in the 
‘Survival of the Fittest,’’ that the earth owes the 
diversity of fruits, flowers, and foliage we _ see 
around us. 
Leaving this record of the past, which is still, in 
parts, more or less obscure, let us consider what is 
going on throughout the vegetable world to-day. 
There are certain types of plant which, owing to special 
peculiarities, are adapted only to a special environment, 
while, again, there are others which, because of certain 
broad features that make for strength, endurance and 
rapid multipheation, are able to flourish in a great 
variety of surr oundings. 
The dock is-a plant of the latter type. Its long 
fleshy tap root goes deep into the earth for food and 
moisture; it stores reserve material against seasons of 
scarcity, and it is, above all, possessed of such enormous 
powers of resistance to drought, that, if taken up and 
left on the surface of the ground till apparently quite 
desiceated, it will yet, when the rains have come, send 
branch roots into the earth, once more become estab- 
lished, and produce flower and fruit. The fruit, too, 
owing to its rough ease, is easily transported on the 
coats of animals, and being light, and able to 
endure prolonged soaking, may float on water for 
considerable distances. The seed, too, possesses creat 
vitality, and, even after being pura deco in the earth 
for some years, will freely germinate when brought 
into regions where oxygen is available. 
The daisy family includes about ten per cent. of all 
known flowering plants and consequently must be well 
equipped to compete in the struggle for existence. 
