the motet, organum, and hocket. He specifies that the motet is to be performed for the clergy before feasts or during celebrations since they would be some of the only people who would appreciate the subtlety of the motet and could appreciate the "finer points of the arts". Musica ecclesiastica Grocheio discusses several aspects of musica ecclesiastica (church music) in his treatise. He describes the use of all of the chants in the Mass, the function of the eight church modes, and the threefold division of musica ecclesiastica into music for Matins, the Divine Office, and the Mass. Manuscripts Grocheio's treatise survives in two manuscripts. One edition of the treatise survives in the British Library, Harley in an anthology of music theory treatises by Guido of Arezzo, Guy of Saint-Denis, Petrus de Cruce, and several anonymous authors. The other edition is located at the Darmstadt University and State Library in another anthology containing writings by David of Augsburg, Hugo of St. Victor, Hugo of St. Cher, and several other anonymous authors. The Darmstadt manuscript is the only copy that credits the treatise to Johannes de Grocheio. Darmstadt, Hessische Landes- und Hochschulbibliothek, MS 2663, ff. 56-59. London, British Library, Harley 281, ff. 30-52. Editions and translations Rohloff, Ernst, trans. Der Musiktraktat des Johannes de Grocheo nach den Quellen neu herausgegeben mit Übersetzung ins Deutsche und Revisionsbericht. Media latinitas musica 2, Gebrüder Reinecke, Leipzig 1943, p. 41-67. Say, Albert, trans. Johannes de Grocheo: Concerning Music (De musica). Colorado Springs College Music Press, translations (1), Colorado Springs 1973 (2nd. ed). Page, Christopher. "Johannes de Grocheio on secular music: a corrected text and a new translation.” Plainsong and Medieval Music 2, no. 1 (1993): 17-41. Johannes de Grocheio. Ars Musice, ed. and trans. Constant J. Mews, John N. Crossley, Catherine Jeffreys, Leigh McKinnon, and Carol J. Williams. Kalamazoo, MI: Medieval Institute Publications, 2011. References Grocheio, Johannes de 13th-century French writers 14th-century French writers Grocheio, Johannes de Grocheio, Johannes de Grocheio, Johannes de French male non-fiction writers 13th-century Latin writers 14th-century Latin writers Medieval music theorists