606 not The Milkweeds. ` > uya 
the conclusion that the warfare there is even more severe than 
it is with the human race, He will find that carnivorous animals 
devour others weaker than themselves; birds feed on grass- | 
hoppers and other insects; these again prey on others; and so | 
the warfare continues down to the minute animalcule which can 4 
be seen only under the microscope, and which swallows other — 
creatures only a little smaller than itself. Not only so, but he 
will find the Carnivora disputing with their own kind; wolves — 
fighting with other wolves; birds contending with other birds 
for the insects they need; and these in their turn fighting their i 
own kind for nearly every mouthful of food. Everywhere he ~ 
will find war being waged continually; so that he must finally 
come to the conclusion that nature is far sterner than man in : 
the struggle for the means of living. 
Perhaps he may think that in the animal world alone this war- 
fare is going on; but if he turns to the vegetable kingdom with 
the idea that here there can be no such struggle, a short time 
will convince him of his mistake. He will not, indeed, as a 
rule, see one plant devouring another in a literal sense; but he 
will find one sort of tree crowding and pushing another, or 
overshadowing smaller plants so that they cannot live; he will 
see them in the fields so close together that he soon concludes — 
they must take more or less moisture and nutriment from each 
other; he will find the roots so crowded and matted together 
that the soil is a mass of them; that here one plant has fastened ; 
itself on another and is sucking its life away; and he will be 
forced at last to give a reluctant assent to the assertion that 
there is warfare among plants as there is among animals, and 
that the difference is one not of kind, but of degree. This con- 
stant, continual, fierce fight is the struggle for existence, in the — 
course of which the fittest will survive. In other words, that — 
plant or animal will be the most likely.to live and continue to _ 
propagate its species which can best succeed in crowding out — 
some of its competitors, and in taking the Sorria they 
need to itself. 
It is for the purpose of carrying on this continual kata 4 
that many structures have become developed. For instance, 
the lion has had his strength increased and his retractile claws 
a sharpened by the constant effort he is obliged to make to con- _ 
quer and carry off his prey. There can be no doubt but that — 
a ee ae ae ee 
ae 
