(for example, El Lissitzky, Kazimir Malevich, Wassily Kandinsky, Fernand Léger, Amédée Ozenfant, Le Corbusier, Paul Klee). Towards the end of the 1920s, the shapes in Baumeister’s pictures grew softer. His paintings moved away from being oriented by the elementary shapes of the circle, triangle, and square towards organic forms. Although this development could also be observed concurrently in the work of other artists of his time, in Baumeister’s case, it was tied to his fascination for the prehistoric and archaic paintings. Baumeister intensely explored artifacts of early paintings and integrated this pictorial experience into his own painting. He identified the symbols, signs, and figures of cave painting as components of a valid archaic pictorial language that he used in his works. These included his increasing number of paintings in "oil on sand on canvas" that, in their materials, also approached the cave painting that Baumeister so admired (beg. ca. 1933). He himself collected examples of prehistoric findings, small sculptures, and tools, and occupied himself with cliff drawings that had been discovered in Rhodesia. This experience was undoubtedly important for Baumeister’s artistic disposition since he, evidently inspired by this rich store of prehistoric works, ultimately used extraordinarily reduced organic shapes for his "ideograms" (beg. ca. 1937). In these works he used a unique world of signs, which he saw as symbols for the laws of nature, their evolution, and human existence. Baumeister’s artistic development was not interrupted when he lost his professorship at the Städel in Frankfurt in 1933. He continued to paint despite political persecution and economic difficulties. His work and its development are correspondingly diverse, even for the period after 1941, when he banned from exhibiting. He was the employed by the Dr. Kurt Herberts & Co. varnish factory in Wuppertal to research antique and modern painting techniques. This protected him politically and also gave him the opportunity to explore the fundamentals of painting. In this way he furthered his knowledge on prehistoric cave painting techniques. At the same time, he looked into Goethe’s theory of plant morphology. Out of this study this "eidos pictures" (eidos: idea) emerged: paintings that, unlike Baumeister’s ideograms, are rich in their variety and coloration. Moreover, these forms are organic, but seem rather than being symbols or signs, are images of simple plantlike and animal life forms. The pictures bear titles such as Rock Garden, Eidos, or Primordial Vegetable. As an indefatigable researcher and