For a list of PM manuscripts, see Crick, SC, pp. 330–32.

Geoffrey included the PM in his next work, the De gestis Britonum(“On the Deeds of the Britons”, hereafter abbreviated DGB). He had finishedthis work by January 1139 at the latest, when Henry of Huntingdon reports hisastonishment at finding a copy at the abbey of Le Bec.3 The count of survivingmedieval manuscripts of the DGB is now 225, making Geoffrey one of the mostwidely-read secular authors from medieval Britain.4

third and final extant work is the Vita Merlini (“The Life of Merlin”, hereafterabbreviated VM), completed around 1150 and extant in only four independentmanuscripts.6 Written in dactylic hexameter, this poem recounts how MerlinSilvester goes mad after battle and retires to the woods to live; this enigmaticand difficult work seems to be deeply in touch with Welsh literature, thoughits ultimate sources are unknown.