the moss to that of the oak-tree, an incredible number of cells come together to form an ordered state; the number of cells in a small plant may be compared with the number of the inhabitants in the most powerful kingdoms; and I have estimated that at least ten million cells live together in a potato five centimetres (about two inches) in diameter, and that a pine-stem twenty-five metres (about eighty feet) high and twenty-five centimetres (about one foot) in diameter, of symmetrical growth, contains more than a hundred milliard wood-cells.
The leading idea that knits the plant-cells into a state-organism is the same as in the bee-hive or the human state, the division of labor. Each cell possesses its individual life and passes through its particular course of development; it, however, does not undertake all the works of life, but limits the circle of its activities so as to reach a greater perfection within a smaller limit. In this it works not for itself alone but for the other cells also, while it commits to them those requirements for the satisfaction of which its individual activity is not sufficient. Thus the different functions are so divided among the different cells that one makes this, another that, occupation its own special business. The cells of the cell-state so arrange themselves in their different offices that they work mutually into each other's hands: one lives for all, all for one. The more perfectly the division is carried out, the more completely can each cell fulfill the duty for which it is designed; the more highly organized is the cell-state, and the higher position does the whole plant take in the order of growths.
As in the bee-hive there are working-bees, so in the cell-state of the plant there are working-cells; other cells are fitted for sexual existence, like the drones and the queen in the bee-hive, so as to insure the production of posterity and the foundation of a new stock.
The cells which discharge the several functions in the plant are not scattered confusedly in the mass, but are always grouped in greater or smaller numbers of individuals precisely adapted for this or that function, and together form a tissue. Plant-anatomists distinguish three kinds of tissues, each of which discharges a particular function: The fundamental tissue is composed of the cells which are the real workers in the state; the circulating tissue, of those cells on which the duty of transportation is laid; the bark-tissues, of those to which is assigned the protection of the cell-state against the outer world. We might designate as a fourth class the reproductive tissues, as including the cells adapted to propagation, which are producing by continuous divisions new colonies, new leaves and flowers, new buds and seeds.
The cell-state is, to speak with Herbert Spencer, organized after the type of an industrial state, in which numerous industrious workmen are co-operating on a footing of democratic equality to ennoble the raw material of lifeless nature and convert it into the precious and diversified productions of life. The fundamental tissue in a measure represents the working-class; trade is represented in the cells of the
