unitary state, the members of which have entirely lost their independence, and in which a single will rules the whole; while we may represent the plant as a freely organized federal state, the members of which, in spite of their resignation to the whole body, have yet preserved a certain degree of independence and self-administration.
In the federal state of the plant the limbs and boughs correspond to the provinces, the leaves to the villages; but the village is not the last member of the chain: it is itself a union of citizens, each one of whom, though a member of the state and the village, is an independent being who lives first for himself, and has his own household, all of whose efforts are first directed to the maintenance of his own existence. But while with a just egoism the citizen knows his own good as his immediate object, he thereby participates directly in the advancement of the state organism and contributes to the support of the whole state. Every citizen goes through his independent development from birth to death; but the village does not die with the death of the individual, for in his stead come his children to fill the vacant place; and the village and state are renewed in the unbroken succession of generations.
It is the same in the plant-state. If we compare the leaf with the village, it also consists of a larger or smaller number of individuals which may be regarded as independent organisms. The citizens, through the union of whom the plant-state is formed, are called by the botanist plant-cells. All plants, without exception, are composed in all their parts of cells, just as every building, from the palace to the hut, consists of building-stones or timbers. Every plant-cell pursues an individual life. Its first effort is only to maintain and develop itself; it takes its own nourishment and assimilates it, and finally dies, after having, as a rule, first left a posterity in its place. As the cells unite to form cell-villages in the leaves, these unite again to form the provinces of the foliage-boughs, and enter into an interchange of life with each other, and so they maintain the life of the whole plant in the same manner as the collective state-life comes into being through the interworking of the lives of the individual citizens. What we see going on in the life of the plant in the germ and shoot, in flower and fruit-bearing, are only head and state actions in the development of the cell-state and its citizens.
Our eyes can not perceive these citizens of the cell-state. It is not strange, then, that their existence escaped the knowledge of naturalists till about two hundred years ago. They would still be concealed, and the key to the comprehension of plant-life would be withheld from us, had it not been for the microscope.
We owe it to the microscope that, where the naked eye perceives only uniform masses, we can now distinguish a wonderful diversity of beautiful tissues; and that where a rigid stillness seemed to prevail, a fullness of life-processes quite incomprehensible to us is concealed.