There was another way in which the conductus was an exceptional genre. It was the only type of
polyphonic composition that was syllabically texted. In contemporary parlance it was musica cum littera
(“music with letters,” i.e., words). And that meant it had to be notated in notae simplices rather than in
ligatures, because ligatures functioned in Notre Dame notation just as they did in plainchant. They were
used only to carry melismas, which means music without text (musica sine littera). There was no
standard method for applying text to notation in ligatures.
The conductus thus exposed the chief shortcoming of the system or practice of “modal” rhythm. The
four-voice Christmas conductus Vetus abit littera from the Florence manuscript (Fig. 6-6) shows how,
and also shows a possible attempt to remedy the situation. (It also has a very interesting, quasi-
modulatory tonal shape, but we’ll let that aspect of the piece speak for itself.)
Until the penultimate syllable of text, the notation consists almost entirely of single notes. If read
strictly according to the rules of modal rhythm, they are all perfect longs, casting the setting in a very
heavy spondaic meter throughout. But that penultimate syllable has a sizable melisma in all voices. A
melisma at the tail end is a standard feature in Notre Dame conductus settings, common enough to have a
generic name. It is called the cauda, which literally means the tail, as in tail end. (The term was re-
introduced into musical terminology centuries later, when Latin had been replaced by Italian as musical
lingua franca: we all know what a coda is and can see how it relates conceptually to the medieval
cauda.)
FIG. 6-6 Vetus abit littera, four-part conductus attributed by some writers to Perotinus (Flo, fols. 10–10v).
Being a melisma, the cauda is written in ligatures. As a second glance at them will show, the ligatures
in question could hardly form a clearer trochaic (“first mode”) pattern. No question, then, that the cauda is
supposed to go tum-ta-tum-ta-tum-ta-tum in good “modal” fashion. And so the question arises: Is the “first
mode” cauda supposed to contrast with the “fifth mode” of the rest of the piece? Or, perhaps, is the cauda
there not simply for the sake of embellishment but also to convey the otherwise unconveyable information
that the whole piece is to be sung in “first mode”? Ex. 6-6a is a transcription of the whole piece in “first
mode,” which turns the accentual pattern of the entire poem quite convincingly into a quantitative musical
meter. But there is no authority to back that decision up; it is simply a preference. To give the other side