One of the greatest and without doubt the most interesting work of art in Siena is Ambrogio Lorenzetti’s fresco cycle of the Allegories and Effects of Good and Bad Government in the Palazzo Pubblico (ca. 1340). This is a detail from the fresco showing the effects of good government in the city: women dancing in the streets, a symbol of civic harmony. Note that on the backs of two of the ladies’ dresses are dragonflies and caterpillars. One interpretation of these motifs is that they support the allegorical function of the women, and their circular dance may allude to springtime festivities often held in medieval towns of Tuscany. Real women in elaborate costume may well have sung and kept rhythm with tambourines during such festivities. The caterpillar signifies metamorphosis into something beautiful, and thus the processes of nature towards the good parallel the metamorphosis of society when good government reigns.