FIGURE 9. Waveforms and power spectra of EODs from Stomatorhinus walkeri (A – D), S. ater (E, F) and S. patrizii (G, H) on the same time scale as those shown in Fig. 5. EOD waveforms are centered about the largest head­negative peak, normalized to the same peak­to­peak height and plotted with head positivity upward for each trace. Power spectra are normalized so that the peak energy is adjusted to 0 dB. Individual specimen numbers are indicated beneath waveforms; F = female, M = male.