I — Axis [CII], spinous process; 2 — Atlas [ CI], posterior tubercle; 3 — Rectus capitis posterior minor; 4 — Superior nuchal line; 5 — Inferior nuchal line; 6 — Obliquus capitis superior; 7 — Mastoid process; 8 — Rectus capitis posterior major; 9 — Atlas [CI], transverse process; 10 — Obliquus capitis inferior;
II — Axis [CII]; 12 — Atlas [CI]; 13 — Mandible;
14 — External occipital protuberance