THE MUSCLES OF THE EYE AND EAR. 55 



and it is upon this lid that the action of the muscle is 

 principally exerted, the eye being covered and closed, by 

 its being drawn upwards over it. 



This muscle may now be divided at its principal 

 origin ; the integument dissected c|uite up to the free 

 edges of the lids, where we carefully divide it all around, 

 in order to remove tliese now unnecessary parts. Reflect- 

 ing the dense tissue above the eye, we behold the 

 organ in situ. 



38. Levator i^alpehrm suj)erioris. — The lower eyelid 



Fk;. 2] .—Mesial aspect of eye of Goose, to show muscular insertions (after Owen), 

 with certain parts removed tliat appear in the original. op. n,, stump 

 of optic nerve : c, obliquus superior ; d, rectus internus ; /, obliquus 

 inferior ; b, rectus inferior ; c, rectus e.xternus ; h, pyramidalis ; h\ its 

 tendon ; q, quadratus ; a, rectus superior. 



is the one which principally closes the eye in the Raven, 

 consequently we find the present muscle but feebly 

 developed, while, on the other hand, the next to be 

 described is quite strongly so. The levator palpebrse 

 superioris arises along a longitudinal line found at about 

 the middle of the roof of the orbit within. The faiut 

 and delicate fibres pass directly outwards to find insertion 

 in the ciliary margin of the upper lid, being best seen 

 rather on the side towards the outer canthus. As in the 



