Fig. 4. Optokinetic response to split optokinesis in the temporo-nasal direction for both eyes with a stimulus speed of 15° s^-1 for the left eye and 5° s^-1 for the right eye. Otherwise the conventions are the same as in Fig. 3. The butterflyfish (A) does not show a fully developed optokinetic nystagmus in both eyes; however, some compensatory strategies can be observed. Left: converging eye movements following the respective stimulus can be observed in both eyes and independent saccades are shown (example at 5 s). Right: both eyes move in the same rotational direction (i.e. to the left or the right of the fish), however, while one eye shows a smooth slow phase in the stimulus direction, the other eye makes several fast phase movements (1-1.5 s; 2.5-4 s), dissociating slow and fast phases between the two eyes. Pipefish (B) and sandlances (C) both respond independently to the different stimuli to each eye.