Over his life, the Dutch graphic artist M.C. Escher created over a hundred ingenious tesselations in the plane. Some were simple and geometric, used as prototypes for more complex endeavors. But in most the tiles were recognizable animal forms such as birds, fish and reptiles. The definitive reference on Escher's divisions of the plane is Doris Schattschneider's Visions of Symmetry, now in a secon