122 



MR. W, OTTLEY ON THE 



[Feb. 4, 



The action of the individual muscles may be thus stated : — 



The superior rectus (.3) turns the eye up and in, 

 inferior rectus (3) ,, 



internal rectus (3) „ 



external rectus (6) „ 



superior oblique (4) ,, 



inferior oblique (3) „ 



down and in, 



in, 



out, 



down and out, 



up and out; 



the numbers indicating the nerves which supply them. 



It is also believed that a very slight rotation of the eye round an 



Fig. 1. 



Fig. 2. 



antero-posterior axis (the visual axis) does normally occur (Bonders, 

 Ann. d'Oculistique, 1877). 



On examining the eye of a fish it is at once evident that the muscles 

 here cannot have the same action as in the human eye. It is seen 

 that here the superior oblique, which has no pulley, must be com- 



