Fig. 4 BACK VIEW OF THE MANDIBULAR JOINT AND OF THE SURROUNDING STRUCTURES
The external auditory meatus (2), lined by the mucosa and braced by its cartilage, still exhibits a circular shape. However, only the upper compartment of the mandibular or jaw joint (17) remains open, the lower by now being covered by the cap-like articular disc. The tendinous attachment of the lateral pterygoid muscle (23) to the condyloid process of the mandible and the capsule of the joint is apparent. The maxillary artery (26), whose origin from the external carotid artery (25a) is visible in Fig. 3, is soon here coursing behind the lower head of the lateral pterygoid muscle (23b). It gives off several branches: noteworthy in the middle meningeal artery (29) which enters the cranial cavity. At the left end of the pterygoid muscle the maxillary artery pushes between its two heads emerging onthe lateral side where it forms a short loop (26, in Fig. 3), after which it again turns inward (26, at the extreme left end of the muscle in Fig. 4), and plunges into the pterygo-palatine fossa (26, in Fig. 5).