Charles Darwin (1809–1882) British naturalist, author of "On the origin of species, by means of natural selection"
volume III, chapter IV: "The Publication of the 'Descent of Man', page 176 http://darwin-online.org.uk/content/frameset?pageseq=188&itemID=F1452.3&viewtype=image; letter to Thomas Higginson (27 February 1873) <br class="br">The Life and Letters of Charles Darwin (1887)