The year is established by the form of address on the printed stationery, used between 1861 and 1869, by the leap years in this period, and by CD’s visit to his brother Erasmus Alvey Darwin’s house at 6 Queen Anne Street, London from 3 March 1868 (Correspondence vol. 16, Appendix II).
CD used the French publisher and bookseller J. B. Baillière et fils to send and receive books between London and New York (see, for example, Correspondence vol. 16, letter to B. D. Walsh, 27 January [1868]). The contents of the parcel have not been identified.