The eighth cranial nerve could, in a sense, be regarded as two separate nerves responsible for two different special senses. The vestibular portion of the nerve transmits information into the C.N.S. arising from receptors responsive to movement and gravitational force. The sense of hearing is of course the role of the cochlear nerve. Although the two parts of the eighth nerve have obviously different functions, there are several characteristics which both portions have in common. They are both special senses, their receptor structures are similar in some regard and the two divisions of the nerve are closely related to each other in their course from receptors to the brainstem.