MUSCLES OF THE EYELIDS. 171 



8', its attachment to the columella nasi, or depressor nasi ; 9, levator labii superioris, 

 and close by it zygomaticus minor ; farther back passing from the + obliquely down 

 towards 8, zygomaticus major ; and between the zygomatici, in shadow, is seen a portion 

 of the levator anguli oris ; 10, quadratus menti or depressor labii inferioris ; 11, trian- 

 gularis oris or depressor anguli oris ; 12, points to the situation of levator menti; 13, is 

 placed on the masseter, it is immediately above the risorius or upper horizontal fibres of 

 the platysma myoides, and a line points from it to the buccinator; 14, platysma myoides; 

 15, placed on the upper part of the sterno-mastoid, points by a line to the posterior belly 

 of the digastric muscle ; 15', the sternal tendon of the sterno-mastoid, a part of its clavicular 

 portion is seen near e: 16, trapezius ; 17, splenius capitis ; +, splenius colli ; 18, levator 

 scapulae; 19, stern o - hy oid ; 20, omo-hyoid ; 21, pectoralis major, its pectoral part ; 21', 

 its clavicular part ; 22, deltoid. 



most conveniently described along with that structure, there are attached to 

 the external ear three larger, but still very slightly developed, muscles, 

 which serve to move it as a whole. 



The auricularis superior or attollens auriculam, the largest of the three, 

 arises in the temporal region of the head from the epicranial aponeurosis. 

 Its fibres are extremely delicate, and radiated in arrangement, and are 

 inserted by a compressed tendon into the cartilage of the ear at the upper 

 and anterior part of the helix and upper part of the concha. 



The auricularis anterior or attrahens auriculam, scarcely separated from 

 the preceding muscle, is pale and indistinct, and is attached to the thin 

 lateral prolongation of the epicranial aponeurosis, from which it passes back- 

 wards to be inserted into the fore part of the helix. 



The auricularis posterior or retrahens auriculam muscle, consists of two 

 or three thin fasciculi, which arise from the mastoid process by short 

 aponeurotic fibres, and are inserted into the back part of the concha. The 

 fibres are much deeper in colour and more distinctly marked than in either 

 of the other auricular muscles. 



ACTIONS. The three auriculares muscles respectively draw the pinna of the ear 

 upwards, backwards, and forwards. In the majority of persons their action is not 

 directly under voluntary control. 



MUSCLES OF THE EYELIDS. These are four in number namely, the 

 orbicularis palpebrarum and tensor tarsi, the corrugator supercilii, and the 

 levator palpebrse superioris. 



The orbicidaris palpebrarum is a thin elliptical muscle closely adherent to 

 the skin, surrounding the fissure between the eyelids and covering their 

 surface, and spreading for some distance outwards on the temple, upwards 

 on the forehead, and downwards on the cheek. The fibres forming con- 

 centric curves are attached by their extremities at the inner angle of the 

 orbit : 1st, to the edges and anterior surface of the tendon afterwards 

 described ; 2nd, to the surface of the nasal process of the superior-maxilla, 

 near the anterior margin of the lachrymal groove ; and 3rd, to the internal 

 angular process of the frontal bone. 



The fibres situated in the eyelids are thin, pale and little curved, and 

 conceal the tarsal cartilages : they are sometimes distinguished by the name 

 " ciliaris." The peripheral fibres, "orbicularis latus," more largely deve- 

 loped, rest on the cheek and margin of the orbit. Superiorly this muscle 

 conceal the corrugator supercilii, with which and the occipito-frontaJis it 

 is intimately connected ; inferiorly it covers the origin of the elevators of 

 the upper lip, part of the common elevator of the lip and nose, and the 

 lachrymal sac ; and externally it lies upon a part of the temporal fascia. 



The tendon of the orbicularis muscle (tendo palpebrarum). At the inner 

 commissure of the eyelids is a small tendon, which is often obscured by the 



