Inferior view of left temporal bone. The styloid and mastoid processes are landmark structures for the attachment of several muscles. Between these processes is the stylomastoid foramen for exit of the extracranial portion of the facial nerve (CN VII). Posteromedial to the mastoid process is a notch, the mastoid notch, for attachment of the posterior belly of digastric muscle. Posteromedial to this notch is a groove, the occipital groove, for the occipital artery on its course into the posterior cervical triangle and scalp. The jugular fossa is a depression on the posterior surface of the petrous temporal bone for the jugular bulb. Immediately anterior to the fossa is the opening of the carotid canal for the internal carotid artery. The mandibular fossa is a depression for the condyle of the mandible and the temporomandibular articulation. Anterior to this fossa is the articular tubercle, a ridge of bone on which the condyle slides during jaw opening and closing. Extending forward from the lateral aspect of the articular tubercle is the zygomatic process that unites with the temporal process of the zygoma to form the zygomatic arch. (Image courtesy of AL Rhoton, Jr.)