OF THE HEAD IN GENERAL. 



33 



Fig. 18. 



below it and behind, a larger one for the submaxillary gland. The 

 upper edge is the alveolar pro- 

 cess, with sockets for sixteen teeth. 

 The inferior edge is the base, 

 thicker in front, with two corners 

 in front giving a squareness to the 

 chin, which is that portion included 

 between the anterior mental fora- 

 mina. 



The ramus'^ is square, and at 

 right angles to the body in man- 

 hood, in youth and old age oblique; 

 externally it is rough for the mas- 

 seter muscle, anterior to which is a 

 groove for the facial artery.'' The 

 internal face has a foramen, posterior mental, ^^ for the entrance of the 

 inferior alveolar artery and nerve. To the edge of this foramen is 

 attached the internal lateral ligament ; near it is a groove** trans- 

 mitting the mylo-hyoidean nerve ; below, is the surface for the inser- 

 tion of the internal pterygoid muscle. The angle^ is rough, has 

 attached to it the stylo-maxillary ligament. The anterior edge of 

 the ramus is continued into the external oblique ridge. ^ The supe- 

 rior part of the ramus has two processes separated by*^ the sigmoid 

 notch. The coronoid process is in front,*" triangular and thin ; it 

 has inserted into its apex the temporal muscle ; in front there is a 

 groove for the buccinator muscle. The posterior is the condyle'* arti- 

 culating in the glenoid cavity of the temporal bone. The neck is 

 narrow, and on the inside of it is a fossa for the insertion of the ex- 

 ternal pterygoid muscle. 



OF THE HEAD IN GENERAL. 



Si/iures. — The principal sutures of the head are the coronal, which 

 unites the parietal and frontal bones ; saggital, which unites the two 

 parietal bones in the adult, and in a child extends to the root of the 

 nose ; occAintal, which joins the parietal and occipital bones ; squcmious, 

 uniting the squamous part of temporal and parietal. Besides these 

 there are others uniting the bones of the face. That part of the 

 suture between the mastoid and parietal bones, is called additamen- 

 tum suturte squamosEc ; and that suture between the mastoid and oc- 

 cipital, called additamentum suturoe occipitalis. 



Fontanels. — These are the deficiencies in the bones peculiar to 

 the fcetal head. The cmterior is large and quadrangular, situated at 

 the junction of the coronal and saggital sutures. The anterior angle 

 is the most elongated. The poste/io?' is small and triangular, situ- 

 ated at the junction of the lambdoidal and sagittal sutures. Besides 



