40 CONSCIOUS NKKVnrs OPERATIONS 



on each side, and having large openings leading into the 

 ear cavities. 4. The sphenoid* forming part of the floor 

 of the brain cavity. 5. The ethmoid, forming part of 

 the floor in front and joined to many of the facial bones. 

 It is perforated for the passage of the olfactory nerves. 

 6. The occipital, a large bone at the back of the head and 

 also a part of the floor of the skull. It is perforated by 

 small holes through which pass nerves, and by a large 

 opening called the foramen magnum for the passage of the 

 spinal cord to its union with the brain. 



37. The Facial Skeleton consists of fourteen bones: 7. The 

 superior maxillary bones, or upper jaw bones, carrying 

 the upper teeth and forming most of the hard palate. 

 8. The malar bones, or cheek bones. 9. The lachrymal 

 bones, near the inner angle of the socket of the eye, and per- 

 forated for the tear ducts. 10. The nasal bones, forming 

 the roof of the nose. 11. The inferior maxillary or lower 

 jaw bone. 12. The inferior turbinate bones, one in each 

 nostril chamber. 13. The vomer, forming part of the par- 

 tition between the nostrils. 14. The palate bones, which 

 complete the skeleton of the hard palate. 



38. The Hyoid. A small U-shaped bone secured by 

 long ligaments to the base of the skull and lying in the 

 neck at the root of the tongue, is called the hyoid bone 

 (Figs. 79, 80, and 82, pp. 136, 138). It furnishes points 

 of attachment for many muscles. 



39. Bones of the Ear. Three minute bones in the middle 

 ear (Figs. 74 and 75), the malleus, the incus, and the stapes, 

 have to do with the conduction of sound. 



40. The Vertebral Column. In a man of average stature 

 the spinal column is about twenty-eight inches in length. 

 It consists of twenty-six separate bones (Fig. 29). The 

 upper part, which includes uiore than half the whole 



