The modern printed editions of the Dominican Chant which, as is well known, differ widely from those of the Roman rite, preserve accurately the text of the Correctorium of Fr Humbert de Romans, who undertook the work at the instigation of the General Chapter of the Order held at Buda in 1254. When at the beginning of the twentieth century the reform of Gregorian Chant was introduced attention was drawn also to the origins of the Dominican version of Plainchant. P. Wagner, the first musicologist to investigate the problem, discovered that remarkable similarities existed between the Dominican and Cistercian tradition of Plain-chant, as can be seen from his Neumenkunde (second edition, 1912, pp. 471 sqq.). But he considered that it was impossible to find out whether Humbert took the Cistercian Chant as a model or whether both versions were derived from a common source; namely the theory of chant used in Paris at that time. No progress has been made in solving this question since the publication of Peter Wagner’s book. Now, at last, Père Dominique Delalande has taken up the examination of the question on a wide scale. From the comparison of the melodies of the Dominican Gradual with those of the Cistercian he comes to the conclusion that the Dominican Gradual was derived from that of the Cistercians.