765 



dationiiiiiscle, oriiers say tiia( it. nets \ ery strongiy, and a tliii-d 

 group states tliat it does work, but only slightly. 



Cw^<AA AJ^OiMy JWy>pUt6^lOA^W n^KHMbt/ h-iM\}y 



■fo n l\ lé Ai Xo 



l^ig. 1. 



Abscis van het physiologisch naaste puni = Absois of the physiologic near point. 



Latent ciliairspiercontractiegebied = Area of latent ciliary muscle conti-action. 



Convergentielijn van Donders = Donders' convergencelire. 



Abscis van het physisch naaste punt = Abscis of the physical near point. 



Manifest ciliairspiercontractiegebied of = Area of manifest ciliary muscle con- 

 accommodatiegebied traction. 



Dr. Fi.iERiNGA and 1 liave tried to solve the foregoing questions 

 by a minute study of the relative accommodation. 



By relative aoconunodation we understand the accommodation at 

 a certain given degree of convergence. A certain connection, probably 

 congenital, exists between uccomniodation and convergence; if a 

 normal emmetropic person wishes to fix his eyes on an object, he 

 must converge as many metreangles as he accommodates dioptrics. 



If, in Fig. J, we plot out the myodioptiies and dioptries on the 

 ordinate, and the metreangles on tiie abscis, then we can draw a 

 line through all the points for which accommodation and conver- 

 gency are alike; if, in our scheme, we take the linear measure for 



