36 



ANATOMY FOE, NURSES. 



[CHAP. IV, 



petrous portions is a 

 socket for the recep- 

 tion of the condyle of 

 the lower jaw. 



The sphenoid bone 

 (sphen, a wedge) is 

 situated at the ante- 

 rior part of the base 



FIG. 33. SPHENOID BONE. Anterior surface. 6, of the skull, articulat- 

 greater wing ; 17, lesser wing. 



cranial bones, which it binds firmly and solidly together 

 form it somewhat resembles a bat with 

 extended wings. 



The ethmoid bone is an exceedingly 

 light, spongy bone, placed between the 

 two orbits and at the root of the nose, 

 contributing to form a part of each of 

 these cavities. The portion of the 

 bone situated at the back of the nose, 

 and closing the skull cavity in front, 

 is pierced by numerous holes, through 

 which the nerves, conveying the sense 

 of smell, pass. Descending from this 

 perforated plate, on either side of the 

 nasal cavity, are two masses of very 

 thin, spongy, bony tissue. 



The irregular bones of the face : 



In 



FIG. 34. ETHMOID BONE. 

 Posterior surface. 2, cribri- 

 form, or perforated plate. 



Malar 2 



Palate 2 



Inferior turbinated 2 



Superior maxillary 2 



Inferior maxillary 1 



9 



The malar or cheek bones form the prominence of the cheek, 

 and part of the outer wall and floor of the orbit. 



The palate bones form (1) the back part of the roof of the 

 mouth ; (2) part of the floor and outer wall of the nose ; and 

 (3) a very small portion of the floor of the orbit. 



