Enclosed in letter from Darwin to [G. H. K.] Thwaites, October 26, [1867], requesting Thwaites to circulate a few "slightly corrected copies" of his queries. One of only five copies known to exist. Darwin utilized the answers he received to his queries in his The Expression of the emotions in man and animals (1872).; Located in folder: Darwin to G. H. K. Thwaites. Item call number: B D25.TH #335.