Sound transmission in the salamander ear.

The mode of stimulation of the ear by sounds is considered in Amphibia, in which it differs among the three Recent orders. Of special interest is the order Caudata, in which this stimulation takes a unique form: sounds applied to the oval window of one ear produce a path of vibratory motion that passes through the brain cavity to the oval window on the opposite side. In this course the vibratory movements traverse both right and left amphibian papillae, and both basilar papillae also in species that contain these endorgans. Thus, in the salamander the hearing is invariably binaural.