MUSCLES OF THE FACE. 



309 



rlor part of the lower jaw next to the chin ; runs obliquely 

 upwards, and is 



Inserted into the edge of the under lip, extends along one half 

 of the lid, and is lost in its red part. 



Use. To pull the under lip and the skin of the side of the 

 chin downwards, and a little outwards. 



Fig. 78.* 



3. Levator Lahii Inferioris, 



Arises, from the lower jaw, at 

 the roots of the alveoli of two 

 dentes incisores and of the cani- 

 nus ; is 



Inserted into the under lip 

 and skin of the chin. 



Use. To pull the parts, into 

 which it is inserted, upwards. 



The three outward are, 



I. Buccinator, 



Arises, tendinous and fleshy, 

 from the lower jaw, as far back 

 as the last dens molaris and forepart of the root of the coronoid 

 process ; fleshy from the upper jaw, between the last dens mo- 

 laris and pterygoid process of the sphenoid bone ; from the 

 extremity of this process it arises tendinous, being continued 

 between both jaws to the constrictor pharyngis superior, with 

 which it joins ; from thence, proceeding with straight fibres, 

 and adhering close to the membrane that lines the mouth, it is 



Inserted into the angle of the mouth within the orbicularis 

 oris. 



Use. To draw the angle of the mouth backwards and out- 

 wards, and contract its cavity, by pressing the cheek inwards, 

 by which the food is thrust between the teeth. — The bucci- 



* a, Depressor labii inferioris. b, Buccinator, c, Levator anguli oris, e, 

 Levator labii inferioris (levator menti ;) this will be best seen in dissection by 

 inverting the lip and dissecting off the mucous membrane. /, Depressor anguli 

 oris. 5, Blasseter. g, Tendon of the superior or internal oblique muscle of 

 the eye, after it passes its trochlea, h, Inferior obliqae. 



