Blue boards with bright gilt titles to the spine. Gilt top edge. Volume One: "The Darwinian Theory" - fourth edition, 1910. Some pencil underling & margin notes, but not extensive. Volume Two: Post-Darwinian Questions, Heredity and Utility - fourth edition, 1916. Interior is crisp, clean and appears unread. Volume Three: Post-Darwinian Questions, Isolation and Physiological Selection - edition not stated, 1914. Interior is crisp, clean and appears unread. All three volumes show light shelfwear and contain the previous owners name in pencil on the front paste down. A very nice set.