sensory cells of the maculae and cristae of the vestibular labyrinth of the inner ear; afferent and efferent nerve fibers of the vestibular nerve synapse with them; from the apical end of each cell a bundle of stereocilia and a kinocilium extend into the otolithic membrane of the maculae or the cupula of the cristae. Type I hair cells are flask shaped and enclosed in calyx endings of afferent neurons.vestibular hair cells.