'Correspondence' presents four series of Bateson's scientific, professional and general correspondence and includes many letters sent by colleagues to his widow in the years immediately following his death. The first series, dating from 1890, 'Single individuals', is chiefly scientific and includes the following correspondents: E. Baur, Sir Francis Darwin, H.M. de Vries, Sir Francis Galton, J.S. Huxley, R.C. Punnett and N.I. Vavilov. The second series, 'General correspondence', is both scientific and general, including correspondents such as A.J. Balfour, J.B.S. Haldane, Kew Gardens, H.F. Osborn and Sir David Prain, and also covering particular topics, e.g. 'Art correspondence' and 'classical scholars'. The third series, 'Miscellaneous letters', is an original series dating from 1889, with all correspondents in a single alphabetical sequence. The fourth series, 'Begging letters', also original, relates to Bateson's efforts to obtain financial support for his experimental work, 1898-1904.