Tight knit polythematic imitative fantasía. In three broad sections, without much sectional delineation. Always forward moving through usual cadential devices. Same formulas as used in Mudarra 25 of two polythematic sections separated by free polyphony. The themes of each outer section are closely related and developmental esp. last section. I is broader than III but both have move rapid succession of cadences than II. A beautiful work. Much use of voice pairs.