( A ) vestibular apparatus, located above the cochlea.
( B ) The base of canals is swollen and is called macula, which contains a projecting ridge called crista ampullaris which has hair cells.
( C ) vestibular apparatus is composed of three semi-circular canals and the otolith organ consisting of the saccule and utricle.
( D ) Each semi-circular canal lies in a different plane at right angles to each other.
