It next ascends to the interval between the transverse process of the atlas and the mastoid process of the temporal bone, and passes horizontally backward, grooving the surface of the latter bone, being covered by the sternocleidomastoideus, splenius capitis, longissimus capitis, and digastricus, and resting upon the rectus capitis lateralis, the obliquus superior, and semispinalis capitis.
12.
Above, it lies upon the rectus capitis lateralis, behind the internal carotid artery and the nerves passing through the jugular foramen; lower down, the vein and artery lie upon the same plane, the glossopharyngeal and hypoglossal nerves passing forward between them; the vagus descends between and behind the vein and the artery in the same sheath ( the carotid sheath ), and the superficial or deep to the vein.