50 



THE CRANIUM AND FACE. 



line above and join the frontal and occipital bones at 

 either end, while below they touch upon the temporal 

 bones, the temporal muscles being attached in part along 

 their lower surface. These muscles are inserted into the 

 coronoid process of the lower jaw, which they thus help 

 to raise and to retract. 



The occipital bone is at the base of the skull and at 

 birth consists of four pieces. In the lower, anterior part 



FIG. 16. Front view of the skull. (After Sobotta.) 



is the foramen magnum, an oval opening through which 

 the spinal cord passes from the skull down into the spinal 

 canal. Half way between the foramen and the top of 

 the bone is the external occipital protuberance for the 

 attachment of the ligamentum nuchse which holds the 

 head erect. The inner side of the bone is deeply concave 

 and is divided by a cross-shaped grooved ridge into four 

 fossae, the internal occipital protuberance being situated 



