322 NATURAL THEOLOGY. 



XX. 



MUSCLES OP THE EYELIDS. 



Even in the action of the muscles of the eye- 

 lids, although the most exposed and familiar parts 

 of any, there is something new still to be observed. 

 The eyeball is held betw^ixt the levator palpehrcB, 

 the muscle which raises the eyelid, and the orbi- 

 cularis, that which depresses it ; the one as it ele- 

 vates the eyelid tending to protrude the eyeball, 

 the other to compress and restrain it. 



In paralysis of the orbicularis, the muscle which 

 closes the eye, the eyeball is protruded ; it starts 

 more forward than is natural ; the eyelid is loose 

 and flabby, and can be lifted like a bit of common 

 skin. 



It is from this protrusion of the eyeball that 

 the upper eyelid is raised, and the lower eyelid 

 depressed, by one muscle. Anatomists have sought 

 for a depressor of the inferior eyelid, seeing that 

 it is depressed ; but such a muscle has no exist- 

 ence, and is quite unnecessary. The levator pal- 

 pebrcB superioris opens wide the eyelids, depress- 

 ing the lower eyelid at the same time that it ele- 

 vates the upper one. If we put the linger upon 

 the lower eyelid so as to feel the eyeball when 

 the eye is shut, and then open the eye, we shall 



