Fig. 1. (A) Lateral view of skull (C. asiatica). The dimensions in the sketch are to scale and illustrate the enormous relative size of the hypertrophied malleus (black shading) as well as its position and orientation within the skull. (B) In order to attain optimal coupling between the skull and the vibration exciter, the skull was divided into two sections by a frontal plane cut and (C) the posterior half was mounted on a stainless steel disc with acrylic resin. The disc was secured to a mounting block, which could be driven by a vibration exciter. Seismic stimuli were applied in two different directions. (D) For lateral stimuli, the malleus heads were within the horizontal plane and the excitation was coplanar but perpendicular to the long axes of the mallei. (E) For vertical stimuli, the skull remained in place but the excitation direction was changed.