Notes, [1918x1945], in the hand of Myvanwy Rhys, including genealogical research of the Rees, Mason and James families, together with notes relating to John Rhŷs's school years, the history of Ponterwyd, and 'Ponterwyd worthies'.
Research notes, 1869x[1940], compiled by Myvanwy Rhys, including transcripts of correspondence, among which is a group of original letters, 1869-1870, from John Rhŷs to Henri Gaidoz, with letters from the latter, and transcripts of letters from John Rhŷs to Edward Clodd, 1897-1900, in the latter's hand; notes relating to reviews of John Rhŷs's books, and letters etc. by him published in various newspapers and journals.