Information on differentia
In the original Cantus index, differentiae were categorized according to their modal type (protus, deuterus, etc.), rather than their specific mode, based on the range of their accompanying antiphons. However, each differentia can be ascribed a specific mode, as shown here. The differentiae are mostly written as part of the main layout of the manuscript, with a few written in the margins. Some of the differentiae in this manuscript are written before the start of the antiphon that they accompany, rather than after the antiphon.
Bain, Jennifer, and Nan Zhang. Inventory of Dendermonde, Sint-Pieters-en Paulusabdij, ms. 9. Edited by Alessandra Ignesti, Clare Neil, and Barbara Swanson. In: Cantus Manuscript Database for Latin Ecclesiastical Chant: Inventories of Chant Sources. Directed by Debra Lacoste (2011-), Terence Bailey (1997-2010), and Ruth Steiner (1987-1996). Web developer, Jan Kolácek (2011-).
Images: Dendermonde, Sint-Pieters- en Paulusabdij, ms. 9, Integrated Database for Early Music (IDEM), Alamire Foundation