mathieu petit-didier, a benedictine monk, published an anonymous volume of "remarques sur la bibliothèque des auteurs ecclésiastiques de m. du pin" (paris, 1691), and this was followed by two other volumes to which the author's name was appended (paris, 1692 and 1696). dupin answered him in his fifth volume and petit-didier responded in the opening part of his second volume of "remarques". petit-didier's observations often seem inspired by prejudices of his time. thus dupin had placed st. macarius the egyptian in the 4th century, to which indeed he rightly belongs. having discovered semipelagianism in this author's works, petit-didier concluded that macarius should come after pelagius and st. augustine (ii, 198). in reality similar ideas had been professed by many before st. augustine's time.