Ptolemais of Cyrene

Ptolemais of Cyrene (Ancient Greek: Πτολεμαῒς ἡ Κυρηναία) was a music theorist, author of Pythagorean Principles of Music (Πυθαγορικὴ τῆς μουσικῆς στοιχείωσις). She lived perhaps in the 3rd century BC, and "certainly not after the first century AD." She is the only known female music theorist of antiquity.