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PHYSIOLOGY FOR NURSKS 



Hypermetropic, or far-sighted, eyes have just the 

 opposite defect. The eye is too short for the convexity 

 of the lens and the cone is intercepted by the retina 



Fig. 31. Errors in refraction: E shows the formation of the image on 

 the retina in the normal or emmetropic eye; // shows the condition in long- 

 sight, or hypermetropia, where the eyeball is too short; M shows the condi- 

 tion in short-sight,, or myopia, where the eyeball is too long. (Pearce-Macleod, 

 Fundamentals of Human Physiology.) 



before its apex is reached. The same blurring occurs 

 as in the myopic eye but for the opposite reason. Hence 

 glasses which converge the rays are here necessary. 

 This condition is usually congenital. 



