This valuable contribution to the study of nature magnificently illustrates and describes the intricate, beautiful, and surprising proportional harmonies found in the world of plants. Although science has explained in great detail the complex chemical and physiological nature of plants, it has neglected the study and recognition of how matter is arranged into the shape and pattern of living things. Goethe's organic concept and Rudolf Steiner's imaginative idea of formative forces have inspired the authors in this work, opening the way to a truly scientific understanding of the way in which the living world is formed. In order to describe these principles of form, it was necessary to follow new ideas contained in modern Projective Geometry -- developing a new geometry of living things. Going far beyond the rigidity and static quality of more familiar geometry, one is introduced to a world of moving forms that change constantly: the great variety of living plants.