As a more urban culture developed, academies provided a means of transmission for speculative and philosophical literature in early civilizations, resulting in the prevalence of literature in Ancient China, Ancient India, Persia and Ancient Greece and Rome. Many works of earlier periods, even in narrative form, had a covert moral or didactic purpose, such as the Sanskrit Panchatantra or the Metamorphoses of Ovid. Drama and satire also developed as urban culture provided a larger public audience, and later readership, for literary production. Lyric poetry (as opposed to epic poetry) was often the speciality of courts and aristocratic circles, particularly in East Asia where songs were collected by the Chinese aristocracy as poems, the most notable being the Shijing or Book of Songs. Over a long period, the poetry of popular pre-literate balladry and song interpenetrated and eventually influenced poetry in the literary medium.