Fig. 3. Velocity of dorsal and anal fin tips during steady swimming at 0.5 and 1.0 L s^-1. Red and blue represent the dorsal and anal fins respectively. At 0.5 L s^-1 the anal fin maintains its smooth velocity sinusoid but the dorsal fin shows comparatively increased acceleration and deceleration and maintains fin maximum velocity for a longer proportion of the stroke cycle. The result is a plateau on the dorsal fin velocity graph containing a series of smaller peaks and troughs at high velocities during the cycle.