Fig. 1. Comparative sketch of adult hagfish, lamprey and zebrafish inner ears. Lateral views with anterior to the left; not to scale. Sensory maculae are shown in dark grey; cristae are shown in light grey. Note the single macula communis in the hagfish and lamprey ear, and the asymmetric arrangement of three separate sensory maculae in the zebrafish ear. AH, V and PH are the anterior horizontal, vertical and posterior horizontal regions, respectively, of the lamprey macula communis. (Adapted from diagrams in Gegenbaur, 1898; de Burlet and Versteegh, 1930; Lowenstein, 1971; Hagelin, 1974; Bang et al., 2001.)