A composite, imperfect text made up of parts of two independent manuscripts, with the early chapters by a third hand; all three hands belong to the same type or school of writing, and cannot be separated by many years.
Hand A (pp. i, 1-25) has 21 lines to the page, with two-line rubric initials to chapters. This is the work of a hand like that in British Museum Caligula MS A. III, i.e. the C manuscripts of the Laws. These early folios were probably written to fill in the lacuna at the beginning of the principal fragment; however, the first and second folios are now wanting. The text corresponds with p. 477, col. 1, l. 5 to p. 482, col. ii, l. 15 of the Myvyrian Archaiology of Wales (Denbigh, 1870). Hand B (pp. 26-101, 146-205) has 30 lines to the page with two-line rubric chapter initials, and rubric headings to certain chapters as in the Myvyrian Archaiology, p. 482, col. ii, l. 15 to p. 511, col. i, l. 29, (531-3), 534-7, l. 3, [lacuna] 538, l. 30 to 539, col. ii, l. 21, (539, col. ii, l. 21 to 540), [lacuna] 541, col. ii to 542, l. 41), [lacuna] (543, col. i-ii, l. 12), 543, col. ii, l. 13 to 545, col. i, (545, col. ii to 547, col. ii, l. 32), 547, col. ii, l. 33 to 553, col. ii, l. 28, (553, col. ii, l. 29 to 554) (where bracketed figures denote text which is summarised in the Myvyrian Archaiology). Hand C (pp. 102-145) has 32 lines to the page, with rubric chapter initials floriated with green, now faded. These folios form the ivth and vth quires of Peniarth MS 44. The text of this version is not in close agreement with that in the Myvyrian Archaiology (p. 510, col. i, l. 48 to p. 531), though the wording is frequently nearly the same. There is a folio wanting between pp. 131 and 132, and between pp. 139 and 140.

A volume containing texts of (a) the fuller version of 'Ystoria Dared' (pp. 1-40), translated by Peter Roberts in The chronicle of the Kings of Britain, 1811, (b) the so-called 'Brut Tysilio' or 'compiled version' of Geoffrey of Monmouth's 'Historia Regum Britanniae' (pp. 41-198), also partly translated by Peter Roberts (op. cit.), and closely allied to the text of British Museum MS Cotton Cleopatra B.v., and (c) 'Brut y Saeson' to the year 1461 (pp. 199-308). Pp. 1-88 are in a late 14th century hand; the remaining pages are in the hand of Gutun Owain, the 15th century bard and herald associated with the abbey of Basingwerk. A note, dated 1630, by Robert Vaughan, Hengwrt refers to the misplacement of many pedigrees, and another note, dated 1809, by Peter Roberts refers to the identification of the volume by William Maurice, Cefn-y-braich.