M. R. James (1862–1936) is probably best remembered as a writer of chilling ghost stories, but he was an outstanding scholar of medieval literature and palaeography, who served both as Provost of King's College, Cambridge, and as Director of the Fitzwilliam Museum, and many of his stories reflect his academic background. His detailed descriptive catalogues of manuscripts owned by colleges, cathedrals and museums are still of value to scholars today. James' catalogue of the manuscripts in the library of St John's College, Cambridge, first published in 1913, is reissued here. It will be welcomed by librarians and researchers alike.