A handbook of anatomy for art students / by Arthur Thomson.

  • Thomson, Arthur, 1858-1935.
Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: A handbook of anatomy for art students / by Arthur Thomson. Source: Wellcome Collection.

    512/594 (page 352)
    The most important of these sinuses in connexion with the face is that found within the upper jaw, a bone, which though apparently solid, displays on section a large cavity in its interior. Besides the function above ascribed to these sinuses, it will be evident that by substituting hollow bones for solid ones the weight of this part of the skull is very much diminished.. Among the most important of the bones of the face as determinants of form are the cheek or malar bones. These impart the width to the upper part of the face. If the finger be placed upon the brows, and the outline of the orbits be traced beneath the skin, these bones may be felt as they form the margin of these hollows to the outer and lower side, lying in this position between the outer parts of the frontal bone above and the upper jaw-bones below. Wide of the orbit the malar bones form the prominence of the cheeks. Posteriorly they can be felt to be supported by an arch of bone which can be readily traced back to the region in front of the ear. This is called the zygomatic arch, and is in part made up of a backward process of the cheek-bone and a forward projection of the temporal bone. Beneath this arch, when the skull is stripped of its fleshy parts, there is a hollow extending up on either side of the head. This is called the temporal fossa, and in it is lodged a large muscle called the temporal muscle. The reader may satisfy himself as to the presence of this muscle by placing his fingers above the zygomatic arch and then opening and closing the mouth alternately. The fibres of the muscle will then be felt contracting, for they are inserted into the lower jaw and help to move that bone (Figs. 194, 195, 200). The zygomatic arches therefore act as buttresses to the cheek-bones at the same time that they allow the fibres of the temporal muscle to pass beneath them to be inserted into the lower jaw. The character of the face largely depends on the cheek-