It was said that a tlieory would be proposed as 

 to the course of the optic nerves ; but in copying 

 the last manuscript from the older one this was 

 omitted. 



It amounted simply to this : 



The optic nerves, after leaving the back of either 

 eye, run together at about a right angle. Some of 

 the fibres cross each other, and some of them, it is 

 supposed, continue on their own side. May it. not 

 be that the crossing ones go with the anterior 

 winding-Kne of their respective nerves, and those 

 which do not cross with its counteracting posterior 

 line ? Thus the crossing fibres of the right optic 

 nerve would go with the anterior left winding-line, 

 and those which keep their side with the posterior 

 right winding-line, in all the spines. 



