Durandus. William Duranti, canonist and one of the most important mediaeval liturgical writers, born about 1237 at Puimisson, Provence; died at Rome 1 November, 1296. His career was most noble and distinguished. A long epitaph upon his monument in Santa Maria sopra Minerva tells the story of his life and gives a list of his works. The most important of these is the Rationale diuinorum officiorum, the first edition of which by Fust and Schoeffer as issued at Mainz in 1459. It has been frequently reprinted, the last complete edition being Naples, 1839. The Speculum Iudiciale and the Commentarius in canones Concilii Lugdunensis II are valuable treatises upon the canons and canonical processes.