The Eustachian tube (or auditory tube) is a tube that links the pharynx to the middle ear. In adults the Eustachian tube is approximately 35 mm long. It is named after the 16th century anatomist Eustachius. Some modern medical books call this the pharyngotympanic tube. Location The Eustachian tube extends from the anterior wall of the middle ear to the lateral wall of the nasopharynx, approximately at the level of the inferior nasal concha. A portion of the tube (~1/3) proximal to the middle ear is made of bone; the rest is composed of cartilage[LINK: http://anatomy.med.umich.edu/head/ear_ans.html] Ear - Dissector Answers at University of Michigan Medical School and raises a tubal elevation, the torus tubarius, in the nasopharynx where it opens. In the equids (horses) and some rodent-like species such as the desert hyrax, an e