3IO THE SENSES 



of these, all but the two last named arise from the apex of 

 the orbital cavity. The recti are inserted into the sclerotic 

 just back of the cornea. The superior oblique runs along 

 the inner aspect of the orbital cavity to a point near the 

 supero-internal angle; here it becomes tendinous, passes 

 through a fibro-cartilaginous ring, and then turns backward 

 and outward to be inserted into the sclerotic between the 

 superior and external recti just behind the center of the 

 globe. The inferior oblique arises just within the orbital 

 cavity near the anterior inferior angle, and passes around the 



FIG. 88. Muscles of the eye and tendon or ligament of Zinn. 



i, tendon of Zinn; 2, external rectus divided; 3, internal rectus; 4, inferior 

 rectus; 5, superior rectus; 6, superior oblique; 7, pulley for superior oblique; 

 8, inferior oblique; 9, levator palpebrse superioris; 10, 10, its anterior expansion; 

 n, optic nerve. (Sappey.) 



anterior part of the globe to be inserted in the sclerotic just 

 below the superior oblique. 



The effect these muscles have upon the movements of the 

 ball is indicated by their origin and attachment. The exter- 

 nal and internal recti rotate it outward and inward, the su- 

 perior and inferior recti upward and downward. The su- 



