A calendar incorporating a series of illustrations, ultimately of classical origin, that depict the labors appropriate to each of the months (for example, the labor for June is reaping, that for August, mowing). Images of the labors of the months began to appear in calendar decoration, along with zodiacal signs, in the ninth and tenth centuries and became increasingly elaborate and prominent during the later Middle Ages. The scenes were usually agrarian in character, but some fifteenth-century manuscripts (notably the Très Riches Heures of Jean de Berry and the Sforza Hours) juxtaposed these with scenes from courtly life.