Very large bifolium leaf of Guido de Baysio’s Rosarium Decretalium with illuminated initials c.1380

This is a very impressive bifolium. The page size of each leaf measures 45cm x 28cm. There are 2 very intricately painted illuminated initials and many other red and blue ink initials. This is an unrecorded bifolium from part I of a manuscript of which part II is now Yale University, Beinecke Library MS 338, bought by Thomas Marston from Laurence Witten in 1958 (B. A. Shailor, Catalogue of Medieval and Renaissance Manuscripts in the Beinecke Rare Book and Manuscript Library, II, Binghampton, N.Y., 1987, pp. 165-66, attributing the illumination to the circle of Jacopino da Reggio). Other leaves from the same manuscript include New York, Columbia University, W. MS. 73; and Los Angeles, UCLA, Rouse MS 9 (S. Hindman in Medieval Manuscripts, Their Makers and Users, A Special Issue of Viator in Honor of Richard and Mary Rouse, Turnhout, 2011, pp. 298-99). Overall a very attractive and impressive bifolium of an unrecorded MS.