It is by precisely the same principle that the ur-plant reveals itself in the plant kingdom as a whole. Just as in the single plant organism the different parts are a graduated revelation of the ur-plant, so are the single kinds and species within the total plant world. As we let our glance range over all its ranks and stages (from the single-celled, almost formless alga to the rose and beyond to the tree), we are following, step by step, the revelation of the ur-plant. Barely hinting at itself in the lowest vegetable species, it comes in the next higher stages into ever clearer view, finally streaming forth in full glory in the magnificence of the manifold blossoming plants. Then, as its highest creation, it brings forth the tree, which, itself a veritable miniature earth, becomes the basis for innumerable single plant growths.