in ▁who ▁ab rid ged ▁it ▁and ▁composed ▁cla us ules ▁and ▁sections ▁that ▁were ▁many ▁in ▁number ▁and ▁better ▁because ▁he ▁was ▁the ▁best ▁composer ▁of ▁desc ant ▁( optim us ▁disc ant or ). ▁This ▁Mag ister ▁Per ot inus ▁made ▁the ▁best ▁quad ru pla , ▁such ▁as ▁V ider unt ▁and ▁S eder unt , ▁with ▁an ▁abund ance ▁of ▁striking ▁musical ▁emb ell ish ments ▁[ col ores ▁ar mon ica e ▁art is ]; ▁like wise , ▁the ▁no bl est ▁tri pla , ▁such ▁as ▁Alle lu ia , ▁Pos ui ▁ad i utor ium ▁and ▁[ Al le lu ia ], ▁N ativ itas ▁etc . ▁He ▁also ▁made ▁three - voice ▁conduct us , ▁such ▁as ▁Salv ator is ▁h od ie , ▁and ▁two - voice ▁conduct us , ▁such ▁as ▁Dum ▁sig ill um ▁sum mi ▁Pat ris , ▁and ▁also , ▁among ▁many ▁others , ▁mon oph onic ▁conduct us , ▁such ▁as ▁Be ata ▁vis cera ▁etc . ▁The ▁book , ▁that ▁is , ▁the ▁books ▁of ▁Mag ister ▁Per ot inus , ▁were ▁in ▁use ▁in ▁the ▁cho ir ▁of ▁the ▁Paris ▁c athedral ▁of ▁the ▁B less ed ▁Virgin ▁up ▁to ▁the ▁time ▁of ▁Mag ister ▁Robert us ▁de ▁S abil one , ▁and ▁from ▁his ▁time ▁up ▁to ▁the ▁present ▁day . ▁ ▁There ▁have ▁been ▁many ▁spec ulative ▁attempts ▁to ▁identify ▁P é rot in ▁with ▁members ▁of ▁the ▁Notre ▁D ame ▁administration , ▁but ▁these