PIETRO DE CRUCE. – Composer and music theorist of the 13th century, possibly born in Amiens (and thus called Ambianensis).
Though a pure representative of the period of the two Francos, he shows a marked tendency toward the 14th century, because his contribution to the technique of musical notation was advanced by him through important innovations, such as the division of the perfect breve into 4 semibreves and the use of the *punctum divisionis* to indicate groups of semibreves equivalent to a breve; he freed the *triplum* from modal rhythm and decisively steered notation toward a more pronounced mensuralism. One of his *tripla* was printed by J. Wolf, in *Geschichte der Mensuralnotation* (Leipzig 1935; II, pp. 1-2 and III, pp. 1-5), and later by J. Roksch, *Polyphonies du XIIe siècle. Le ms. H. 196 de la faculté de Médecine de Montpellier* (Paris 1936; I, facs. f. 273-75; III [transcription], no. 254, pp. 81-84). Luisa Cervelli