So far: There are only two known calendar leaves, one sold at Sotheby’s in 1985 and now untraced, and the other at Harvard, Houghton MS Typ 956.1 (shown here). The leaf sold at Sotheby’s preserved February on the recto and March on the verso. The days alternate blue/red/blue/gold, so the use of color is not helpful in determining relative import of particular days. The number of office lessons for each feast is indicated: 3, 6, 9, or, for lesser feasts, the note “Com.” indicating that the liturgy is to be drawn from the Commons. The 9-lection offices offer no surprises: Apostles, Marian feasts, Archangel Michael, and the patristic saints Augustine, Jerome, Benedict, and Gregory. Among the other saints listed in the extant leaves are several of regional import, such as Ansbertus of Rouen and Desiderius of Vienne, Arnulf of Metz, and the abbot Philibertus. All are consistent with Beauvais – and Augustinian – use. The surviving leaves also include a fairly common set of Egyptian Day verses; January would have begun the series, with “Prima dies menses, et septima tuncat ut ensis” (Walther 14563). This set of verses is particularly popular in England, but it is not unknown in France.
Lingering questions: It is somewhat surprising that the calendar entries record office lessons instead of the expected Mass rankings (simplex, duplex, etc.). However, other French mass books from this period - such Morgan Library MS M.115 (a gradual) and MS M.201 (a missal) - have rankings via lessons as well (with thanks to Roger Wieck for the comparables).