Kunstformen der Natur, or Art Forms in Nature, encapsulates biologist Ernst Haeckel’s response to Charles Darwin’s On the Origin of Species. Haeckel published these exquisitely rendered depictions of flora and fauna in ten installments of ten illustrations from 1899 to 1904, aiming to widen the general public’s understanding of naturalism. Haeckel also clearly saw his illustrations as more than just scientific documentation: in introducing one of his plates, he wrote that its patterns would not be out of place in embroideries or on urns and bottles. Haeckel’s elaborate forms have been called a precursor to Art Nouveau, and his influence even stretched to architecture. These illustrations derive from a copy of Kunstformen der Natur in the Case Book Collection in the Prints and Photographs Division of the Library of Congress. The Library holds over 173 million items in almost all media and in more than 470 languages.