Ernst Haeckel. Biologist. Zoologist. Artist. Irregular symmetry dominates his work.
He idealizes natural forms in the same way that conceptual artists and mathematicians idealize geometry.
His drawings were published as a book, The Art Forms of Nature (that's a free download, by the way).
MC Escher. One of the most famous Dutch artists of the past century.
Escher made prints and woodcuts based upon symmetry, rotations, and translations. He often based his designs upon well-known polygons.
Escher would create tessellations and tile the plane of his pictures by repeating a common visual motif.
