Fig. 4. Representative time course of I_sc* across split lamellae of posterior gills of C. granulatus, showing the influence of external addition of 50 mmol l^-1 CsCl (1). At (2) CsCl was also added to the internal bath as a control for diffusive movements of Cs⁺ and Cl^-. The vertical current deflections are due to 1 mV voltage pulses and reflect the uncorrected conductance across the preparation.