THE CRYSTALLINE LENS 



595 



When it is first formed each prism exhibits a nucleus which per- 

 sists for some time, but gradually disappears as in the process 

 of growth the older fibres become farther and farther removed 

 from their source of nutrition, the lymph and the aqueous hu- 

 mor in which the surface of the lens is bathed. This change is 

 accompanied by a hardening or comification and slight shrinkage 



a be 



FIG. 438. THE NUCLEAR ZONE AT THE MARGIN OF THE CRYSTALLINE LENS OF A CHILD'S 

 EYE, SHOWING THE TRANSITION OF THE LENS EPITHELIUM TO THE LENS FIBRES AND 

 THE ATTACHMENT OF THE SUSPENSORY LIGAMENT. 



a, lens fibres ; 6, lenticular epithelium ; c, capsule of the lens ; 

 Hematein and eosin. x 273. 



suspensory ligament. 



of the lens fibres, so that those prisms which come to occupy the 

 center of the lens form a dense, hard mass of non-nucleated fibrous 

 cells with faintly serrated margins; the peripheral fibres retain 

 their smooth edges and their nuclei, and form a protoplasmic mass 



