A manuscript in three parts. The first part, possibly in the autograph of Thomas Jones (alias Twm Siôn Cati), comprises heraldry, with coloured illustrations of the coats of arms of the Britons and of the princes of North and South Wales, together with a number of their pedigrees (pp. 1-136). The second part comprises the pedigrees of the mothers of some of the principal families in Wales, together with a description of their coats of arms (pp. 137-178). The third part comprises poetry, a large portion of which is in the autograph of John Jones, Gellilyfdy (pp. 179-202).