170 MYOLOGY, OR ANATOMY OF MUSCULAR SYSTEM 



at the back of the concha. All of the ear muscles are more 

 or less connected. 



Actions. The frontales elevate the eyebrows, draw the 

 scalp forward, and wrinkle the forehead transversely; occipi- 

 tales draw the scalp back or may alternate with the frontales. 

 Most persons have only partial control, best in case of frontales. 

 The actions of the ear muscles are slight or nil; the anterior 

 makes tense the temporal fascia, and has no effect on the 

 ear; they may enlarge the entrance to the external ear. 



THE MUSCLES OF THE EYELIDS AND EYEBROWS 



M . orbicularis oculi, p. n., has three parts, is thin and elliptical, 

 covers the eyelid, and extends some distance on the forehead, 

 temple, and cheek. 



The pars palpebralis, p. n., is contained in the eyelids, rises 

 from the upper and lower margins of the internal tarsal liga- 

 ment, and passes out in a slight curve to the external tarsal 

 ligament. A thicker fasciculus along the free margin of each 

 lid is the ciliary bundle. 



The pars orbitalis, p. n., is larger and stronger, attached to 

 the nasal process of the superior maxilla, inner part of the 

 orbital arch, and externally to the cheek, forming a series of 

 concentric loops. The musculi malaris of Henle are the lower 

 converging fibers of the orbital part, passing to the skin of 

 the cheek and muscles of the upper lip. 



The pars lacrymalis, p. n. (tensor tarsi or Homer's muscle), 

 extends from the lacrymal crest behind the sac, and divides into 

 two slips behind the lacrymal canals for the ciliary bundles 

 of the orbicularis. 



The internal palpebral ligament (tendo oculi) is 2 lines long 

 and attached to the nasal process of the superior maxilla in 

 front of the lacrymal groove; thence it passes to the inner 

 commissure of the eyelids, splitting and terminating on the 

 tarsi; it crosses the lacrymal sac in front, and gives off a pro- 

 cess which passes behind the sac to the crest of the lacrymal 

 bone. 



The external palpebral ligament is weaker, and attaches the 

 lid to the malar bone. 



The corrugator supercilii (described by Henle as a part of 



