(DURANDUS or DURANTUS), Guillaume, surnamed Speculator, was born about AD 1230 at Puimosson, in France. Studying at Bologna and Modena, he became a learned ritualist, and a great favorite of popes Clement IV and Gregory X. He was appointed by the latter pope legate to the Council of Lyons in 1274, and bishop of Mende in 1287. He died ill Rome November 1, 1296. His principal works are Speculum juris (Strasburg, 1475, 4 parts, and many editions later): Rationale divinorum officiorum (Mayence, 1459, fol.; Augsb. 1470, fol.; Rome, 1473, 1477, fol.; Ulm, 1473, 1475, fol.). The first book of the Rationale has been translated, under the title The Symbolism of Churches and Church Ornaments, by J. M. Neale and B. Webb (Leeds, 1843, 12mo).