Mahavira had eleven principal disciples, who founded the original schools (gana) of Jainism. They are shown teaching, a gesture appropriate to those who embody and transmit the doctrine. All the disciples predeceased the jina except two—Indrabhuti, who succeeded as head (sthavira) of the order, and Sudharman, who in turn became head upon Indrabhuti's death a month after that of his master. Hence all spiritual descendants of Mahavira come from the line of Sudharman. Each disciple is dressed in the white robes of the Svetambara sect, has a small broom on his lap (for harmlessly brushing away insects), and a cloth facemask, or mohapatti (to prevent inadvertently swallowing even microscopic life forms), over his right shoulder. At the center of the composition is the mystic om-hrim symbol, an ancient mantra for purity used to evoke the essence of the siddhachakra (circle of jinas), the essence of the Jain doctrine.