Hearing 10. What is the function of each of the following anatomical features of the ear: External ear - External acoustic meatus - Tympanic membrane - Oval window (deep to stapes) - Auditory ossicles - Bony labyrinth - Vestibule - Vestibular nerve - Semicircular canals - Cochlea - Cochlear nerve - Pharyngotympanic (auditory) tube (eustachian tube) - .