552 



A MANUAL OF VETERINARY PHYSIOLOGY 



axis, and Y to theright — viz., on corresponding points — by which 

 means, provided direct fibres exist in the optic nerves, so as to 

 allow the impressions from the two right halves of the retinae 

 to pass to the right, and from the two left halves to pass to the 

 left brain, the object is seen singly, with good perception of depth 

 and solidity, but with loss of range. No matter how greatly the 

 L R 



Fig. 169. — Diagram illustrating Corresponding Points in the Human 

 Eye (Foster). 



' x' y' are points in the right eye corresponding to z x y in the left eye ; v. 1. visual 

 axis. The two figures above illustrate the corresponding points on the retina 

 described in the text. 



eyes of herbivora may be converged in order to see an object, the 

 rays of light do not fall on the same side of the retina, but on 

 opposite sides of it ; the diagram (Fig. 170) will make this point 

 clear. The outer part or temporal side of the retina in the horse 

 corresponds with the temporal side of the opposite eye ; while 

 the nasal side cannot correspond with the nasal side of its 

 fellow, as it is not possible for a ray of light from an object to 

 strike both nasal sides at one time. 



