A parchment leaf, with sides numbered A20 (recto) and A21 (verso), within a larger collection titled Fragments notés d'antiphonaires et de breviaires, containing three short compositional sketches in various states of completion. The music is composed as florid two-part counterpoint on a plainchant ground.
The A20 side preserves a two-part composition in both an earlier version (crossed out), and a final version with a few crossed out and corrected notes in the treble part. The page is headed with the text Domine Deus homo. The A21 side preserves two distinct compositions in various states of completion. The top two staves preserve the tenor and simple treble harmonization of one composition, and the third and fourth staves contains a florid melodic elaboration of the music on the second stave, intended to accompany the tenor line on the topmost stave. It includes coloration via full note forms to represent imperfect values. The final two staves preserve a distinct piece in an early stage of composition (tenor on top, treble harmonic sketch on bottom), which was probably intended to be elaborated (either in written form or improvised), as per the piece above it.
Michael Scott Cuthbert suggests that the chant may be Cumque audisset populus quod Jesus from the procession for the second Passion Sunday or perhaps Ad te Domine levavi animam. He notes that it is an example of Cantare Super Librum of the type that Tinctoris discusses. Cristina Alís Raurich notes that the chant source for the tenor of the second of the two pieces on A21 is likely the responsory Benedicat nos deus deus noster for Trinity Sunday.
The margin of the verso side of the previous leaf in the collection (numbered A17) also contains some added fragments of musical notation, seemingly in the same hand as A20-21, possibly relating to the music of A20. Note that there is no leaf with page numbers A18 and A19 in the digitized collection.
The collection of musical fragments is held by the Abbaye Saint-Pierre de Solesmes library; digitized versions of their musical manuscripts are made available through the Sarthe departmental archives. This fragment was discovered in 2012 by Dominique Gatté. Description updated 2021, R. Dudas.