Abstract
It has been reported that sound pressure values in the audiogram of marbled sole, which do not have swim bladders, are as low as those of fish that have swim bladders when the audiogram was measured in water using two air loudspeakers to eliminate the water displacement. In the present experiment, sound pressure values in the audiogram of 10 marbled sole Pleuronectes yokohamae were determined using sinusoidal sound pressure as a stimulus to fish removed from water. Sound pressure values in the audiogram obtained by the present method were higher than those obtained in water. This difference was presumably due to inner ear or lateral line sensitivity to water displacement around the center of the water tank.