218 



GENERAL REMARKS ON THE SKULL. 



The nose or nasal fossce are two cavities situated upon 

 either side of the median line, and separated by the vomer 

 and middle septum of the ethmoid. They are bounded ante- 

 riorly and superiorly by the nasal bones , cribriform plate of 

 the ethmoid and sphenoid bones, infer iorly by the palatal 

 processes of the superior maxillary and palate bones, and 

 externally by the nasal processes of the superior maxillary, 

 lachrymal, ethmoid, palate, and inner plate of the pterygoid 

 process of the sphenoid. 



Each fossa contains three turbinated bones, a superior, 

 middle and inferior, with three corresponding meatuses. 

 FIG. 54. The superior meatus communi- 



cates with the posterior eth- 

 moidal and sphenoidal cells 

 and the spheno-palatine fora- 

 men. The middle meatus, sit- 

 uated between the upper and 

 lower spongy bones, looks into 

 the antrum, and connects with 

 the anterior ethmoid cells and 

 frontal sinuses. 



The inferior region or base 

 of the skull is v.ery irregular 

 and reaches from the nasal 

 process of the os frontis to the 

 external occipital protuberance. 

 It is divided into three re- 

 gions, an anterior, middle and posterior. The anterior ex- 

 tends from the superciliary arches of the frontal bone to 

 the pterygoid processes of the sphenoid, and includes the 



FIG. 54 represents an external view of the Base of the Cranium, aa Hard 

 palate. & Foramen incisivum. c Palate plate of the palate bone, d Point 

 for attachment of azygos uvulae muscle, e Vomer dividing posterior nares. 

 / Internal or pterygoid process, g Pterygoid fossa, h External pterygoid 

 Process, i Temporal fossa, j Cuneiform process of occipital bone, k Fo- 

 ramen magnum. I Foramen ovale. m Foramen spinale. n Glenoid fossa, 

 o Meatus auditorius externus. p. Foramen lacerum anterius. q Foramen 

 caroticum. r Foramen lacerum posterius. s Styloid process, t Stylo mas- 

 toid foramen, u Mastoid process, v Condyles of occipital bone, w Poste- 

 rior condyloid foramen. 



