ARCHITECTURE AND COMPOSITION OF THE MUSCLES THAT DRIVE STOMATOPOD EYE MOVEMENTS

1. The peculiar structure of the stomatopod eye requires it to make complicated movements. These include slow 'scans', which relate to the animal's colour vision system, as well as faster 'saccades'. 2. The myology of the eyecup is investigated and shown to consist of eight individual muscles which are divided, on kinematic grounds, into six functional groups. 3. These groups form three pairs of dominant prime movers, with each having primary control over one of the eye movement axes (longitude, latitude and bearing). This is important as it allows each rotational axis to move independently of the other two. 4. Histochemical typing reveals at least four distinct classes of fibre within each muscle. 5. The relationship between the number of types of fibre and classes of eye movement is discussed, as are the implications of coordinate prime movers for neuromuscular control.