Cartilage of external acoustic meatus

The external acoustic meatus is formed partly by cartilage and membrane, and partly by bone, and is lined by skin.

The cartilaginous portion (meatus acusticus externus cartilagineus) is about 8 mm. in length; it is continuous with the cartilage of the auricula, and firmly attached to the circumference of the auditory process of the temporal bone. The cartilage is deficient at the upper and back part of the meatus, its place being supplied by fibrous membrane; two or three deep fissures  (Notch in cartilage of acoustic meatus ; Santorini's)  are present in the anterior part of the cartilage.