282 



THE MUSCLES OF THE HEAD AND NECK. 



it runs horizontally outwards to the inner commissure of the eyelids, where it 

 divides into two thin fibrous lamellae, which diverge and terminate on the tarsi. 



Fig. 267. SUPERFICIAL AND DEEP MUSCLES OP THE HEAD AND NECK, FROM BEFORE. 

 (AJlen Thomson, after Bourgery.) 



On the left side, the platysma alone has been removed ; on the right side, portions of the zygomatic 

 arch and clavicle, the superficial muscles of the cranium and face, the masseter, trapezius, sterno- 

 mastoid and pectoralis major muscles have been removed, a, lower lateral cartilage of the nose ; b, 

 upon the lobule of the right ear, points to the coronoid process of the lower jaw ; c, hyoid bone ; d, 

 symphysis of lower jaw ; e, upon the groove of the first rib, lying in which is the cut end of the sub- 

 clavian artery ; /, glenoid cavity of the scapula ; g, base of right zygoma ; h, temporal crest of frontal 

 bone ; i, orbital arch ; 1, frontalis muscle ; 2, superior auricular ; 2', anterior auricular ; 3, corrugator 

 supercilii ; 4, orbital portion of the orbicularis palpebrarum ; 4', palpebral portion ; below i, the 

 expanded insertion of the levator palpebrse superioris in the eyelid ; 5, pyramidalis nasi ; 6, insertion 

 of compressores naris on dorsum of nose ; 7, levator labii superioris alasque nasi ; 8, left half of orbicularis 

 oris ; 8', outer part of the same on the right side, the inner part being removed ; 9, levator labii 

 superioris ; +, zygomaticus minor ; 10, zygomaticus major ; 11, depressor anguli oris ; 12, depressor 

 labii inferioris ; d, cut ends of levatores menti ; 13, placed on the left masseter, points to the bucci- 

 nator ; 13', buccinator of the right side, a portion of the parotid duct passing through the muscle ; 14, 

 levator anguli oris, seen also on the left side behind the zygomaticus minor ; 15, sterno-mastoid, its 

 sternal head, and 15', its clavicular head ; 16, sterno-hyoid ; 17, posterior, 17', anterior belly of omo- 

 hyoid, and 17", portion of deep fascia binding down its central tendon ; 18, sterno-thyroid ; 19, thyro- 

 hyoid ; 20, part of constrictors of pharynx ; 22, trapezius ; 25, levator scapulae ; 26, scalenus posticus ; 

 27, scalenus medius ; 28, scalenus anticus ; 29, 29', pectoralis major ; 30, pectoralis minor. 



