REGENERATION OF THE LENS IN DIEMYCTYLUS 405 



take sometimes a slightly downward direction. I am inclined to 

 think that some factor influencing the direction of the lens fibers 

 might also exist in the iris itself, because the direction of the axis 

 of the lens seems to be vertical to the stalk of the lens, even in 

 abnormal position. 



Regeneration jrom transplanted pieces of iris 



Fischel and Wachs studied cases where the lens regenerated 

 from isolated or transplanted pieces of iris. In fourteen larvae 

 Wachs cut the piece from the upper iris after extraction of the 

 lens and left it in the posterior chamber. He found after some 

 time that in six cases the pieces had slipped out, in one case it 

 had remained in the corneal wound, in six cases they had fused 

 with the iris, and in one case a lens was formed from the isolated 

 piece, though incompletely. He transplanted also pieces of iris 

 taken from other animals into the eyes of three specimens, but 

 in all cases the pieces fused with the iris and then started to form 

 lenses. 



In fifteen specimens I made transplantations of upper iris 

 pieces, taken from other individuals, into eye cavities. Exami- 

 nation after from thirteen to thirty-three days revealed that the 

 pieces had remained intact in twelve cases; in nine cases they 

 were in contact with the corneal wounds and in three cases they 

 were apart from the cornea. The remaining three cases presented 

 no trace of the transplanted pieces. None of these twelve cases 

 gave pictures of regeneration, except that there was distinct depig- 

 mentation in one case. 



Then I tried to transplant the upper iris pieces to the retina. 

 Twelve specimens were operated upon and examined after from 

 nineteen to twenty-six days. The results were as follows: In 

 three cases the iris pieces were absent in nine cases the trans- 

 plantation was successful. Among the nine successful cases, five 

 showed regeneration (four in the retina and one in the anterior 

 chamber), and four cases showed no regeneration. 



Description of the regenerated cases follows: 



