On 1st July 1858 Charles Darwin and Alfred Russell Wallace laid before the Linnean Society their independent but closely approximate theories of biological evolution. Next year the centenary of that event—I suppose the greatest intellectual event of the nineteenth century—will be celebrated in a variety of ways and places. The steadfast gaze of the Prince Consort, from beneath his gilded tabernacle in Kensington Gardens, will encompass an international throng of celebrants at the doors of his great rotunda across the road; and we may imagine his puzzled but inquiring spirit hovering a trifle uneasily over the commemoration of an event which marked, if not darkened, his declining years. I trust that we ourselves shall, at the proper time, respectfully recall a moment which was to mean only less to the humanistic than to the biological sciences.