Fig. 7. Monocular optokinetic stimulation to the left eye (at 15 ° s^-1) while the right eye receives visual input in the form of a stationary grating. The butterflyfish (A) shows conjugent optokinesis in both eyes, whereas in both the pipefish (B) and the sandlance (C) the eyes are unlinked and only the stimulated eye shows a slow phase in the stimulus direction. However in the pipefish, the eyes are approximately correlated in the direction in which they are moving, as seen during spontaneous eye movements.