[Kinematic transmission-coefficient and the four-bar-system as a function-parameter and a form model for the mandibular depression-apparatus in Teleostei (author's transl)].

Through chains of ligaments and bones, which can be reduced to four-bar-systems (fbs), contraction of the sternohyoid and of the opercular levator muscle result in mandibular depression. Comparatively the opercular fbs transmits movement more efficiently than the hyoid fbs which, consequently, transmits force more efficiently.