In the following correspondence, which mostly relates to the various aspects of Pamplin's business career, are represented many of the leading botanists of the middle decades of the nineteenth century. A similar, though larger, collection is in the Archives Department of the University of Wales, Bangor (Pamplin Papers); and other letters, diaries and notebooks are held at the National Library of Wales (MSS 7492-7509). The following letters are mounted on paper, frequently two letters to a sheet. The arrangement is generally (but not exclusively) alphabetical, and the letters have been numbered according to their positions in the sequence, even if they are out of their strict alphabetical order.