58 



EVOLUTION OF THE HUMAN EYE 



he observed an increased projection of the anterior surface 

 of the lens, but the increased refraction amounted only to 

 2 or 3 D. In the solipedes and ruminants he estimated the 

 range as from \ to 2 D. In the hare and rabbit he totally 

 failed to discover any change, either after administration 

 of miotics or after electric stimulation. 



Fia. 9. — Ciliary body of the echidna. 



Priestley Smith, 30 by examining rabbits' eyes with the 

 shadow test and the faradic current, convinced himself 

 that there was some accommodative change, though in 

 several it was slight and very transient. 



In the horse and dog and probably in most wild mammals 

 the refraction is hypermetropic, so that, their accommo- 

 dation being feeble, their near point cannot be nearer than 

 one or two meters away. Barrett thoroughly atropinized 



