1 In L'art harmonique aux XIIe et XIIIe siècles (Paris, 1865), which presents a study and edition of the manuscript ‘Mo’ (Montpellier, Bibliothèque Interuniversitaire, Section de Médecine, MS H 196), one of the largest thirteenth-century motet sources (facsimile and modern edition in Yvonne Rokseth, Polyphonies du XIIIe siècle Le manuscrit H 196 de la Faculté de Médecine de Montpellier, 3 vols. in 4, Paris, 1935–39).Google Scholar

2 Ludwig, Friedrich, Repertorium organorum recentioris et motetorum vetustissimi stili, i. Catalogue raisonné der Quellen, pt 1 Handschriften in Quadrat-Notation (Halle, 1910).Google Scholar

3 In fact, the current edition does not have barlines, nevertheless, periodic behaviour is a fundamental quality of Parisian polyphony.Google Scholar

4 See Scriptorum de musica medii aevi nova series, ed. Edmond de Coussemaker (Paris, 1864–76), i, 327ff; trans. Luther Dittmer, Anonymous IV, Musical Theorists in Translation, 1 (Brooklyn, 1959).Google Scholar

5 Principally the edition by Heinrich Husmann, Die drei und vierstimmigen Notre-Dame Organa. Kritische Gesamtausgabe, Publikationen älterer Musik, 12 (Leipzig, 1940; repr. Hildesheim and Wiesbaden, 1967). Parts of the two-part repertory have also been available in transcription, if not edition, in William G. Waite, The Rhythm of Twelfth-Century Polyphony Its Theory and Practice (New Haven and London, 1954), and Rebecca Baltzer, Transcriptions of the Repertory of Two-Voice Notre Dame Clausulae (Ann Arbor, 1974)Google Scholar

6 Polyphonic Music of the Fourteenth Century, ed Leo Schrade, Frank Ll Harrison et al (Monaco, 1956–)Google Scholar

7 In this respect, Fritz Reckow's study ‘Das Organum’, Gattungen der Musik in Einzeldarstellungen: Gedenkschrift Leo Schrade, ed Wulf Arlt, Ernst Lichtenhahn and Hans Oesch (Berne and Munich, 1973), 434–96, stands alone as an extended and concentrated consideration of compositional intention and process in two-, three- and four-part organaGoogle Scholar

8 The ‘Magnus liber’ is a collection of two-part organa that survives today only in manuscripts dating from a period (principally the mid-thirteenth century) substantially later than the period of their first composition The form in which these organa are recorded may not, therefore, directly represent their state when first composed as a liturgical repertory before 1200 The three main sources are ‘W₈’ (Wolfenbüttel, Herzog-August-Bibliothek, MS, Helmstedt 628 (Heinemann catalogue 677); ‘F’ (Florence, Biblioteca Medicea-Laurenziana, MS Pluteo 29 1); and ‘W₂’ (Wolfenbüttel, Herzog-August-Bibliothek, MS Helmstedt 1099 (Heinemann catalogue 1206).Google Scholar

9 Why this organum was excluded from Husmann's edition remains unexplained.Google Scholar

10 Husmann, , Der drei- und vierstimmigen Notre-Dame-Organa, clausulae nos. 9, 11.Google Scholar

11 The second-mode passage may also be read as upbeat first-mode (on this, see below)Google Scholar

12 The same melody notes form the tenor line of the two-part Descendit de celis recorded in F (f. 65^v).Google Scholar

13 On the various ways of performing the Alleluia see Hiley, David, Western Plainchant: A Handbook (Oxford, 1993), 130.Google Scholar

14 The Works of Perotin, ed. Ethel Thurston (New York, 1970).Google Scholar