REGENERATION OF THE LENS IN DIEMYCTYLUS 403 



of the inner layer is rather hmited in its extent. Thus the pupil 

 has in its upper margin the cut and the intact edge of the iris. 

 The lens vesicle regenerated from the intact side and not from 

 the cut edge. 



B. Thirteen days after operation. In this case also the iris flap 

 fused with the lower iris edge ; but, in contrast to the former case, 

 regeneration took place both from the cut iris edge as well as from 

 the flap, the latter being converted totally into an incomplete 

 lens vesicle. 



C. Fourteen days after operation (fig. 1). The stump of the 

 iris flap fused with the original upper iris, while the middle part 

 of the flap is free from it. Almost the whole flap is changing into 

 a lens vesicle, which turns toward the cornea. The cells enclos- 

 ing the vesicle are columnar, pigment-free, and arranged partly in 

 two layers. The cavity contains pigment cells and clusters. It 

 can be easily concluded that the vesicle is the flap itself, because 

 the iris stroma is attached to its anterior side. Although the cut 

 edge of the original iris is quite free and two epithelial layers are 

 fused together, no indication of true regeneration, such as thick- 

 ening and depigmentation of the epithelium, can be seen, except 

 that there is slight decrease of pigmentation. 



D. Twenty-eight days after operation (fig. 2). In this case the 

 flap remained unchanged and lens regeneration started from the 

 cut edge of the iris. A microscopical study reveals a well de- 

 veloped lens vesicle between the original iris and the flap, which 

 is closely attached to the vesicle and gives no depigmentation or 

 other sign of regeneration. As the lens vesicle is pretty well de- 

 veloped, there is no connection with the cut edge of the iris, 

 though in the inner layer distinct depigmentation is visible. This 

 vesicle was formed undoubtedly from the upper iris. 



As the results are difl'erent in the individual cases, no general 

 conclusion can be drawn from this experiment. 



