Music of the Trecento system of division of the breve into 2, 3, 4, 6,8, 9, or 12 semibreves (later minims) with dots (singular "punctus divisionis") indicating breaks at the end of a breve (however, Marchetto never used a term 'punctus divisionis'). Although more Trecento music is written in the international system of notation descended from Franco of Cologne and Philippe de Vitry than in the Marchettian system (and there exist a few, mostly instrumental, works not of Italian origin that use this system), nonetheless, Marchetto's contribution to rhythmic notation is so connected with the Italian Trecento that it is often referred to as
Grace note the bar in which they are contained - and therefore, do not require other notes to be dropped from the bar to keep the time signature intact. In bagpipe music there is extensive use of grace notes. Indeed, because the chanter is not tongued but supplied by a continuous air source from the bag, grace notes are sometimes the only way to differentiate between notes. For example, inserting a grace note between two crotchets (quarter notes) played at the same pitch is the only way to indicate them as opposed to them sounding like a single minim (half note). Various