PI. IV. 



Fig. 8. A place in a depigmented section where no dilatator has developed, but where the 

 cells in the hindmost layer of iridian epithelium have assumed a marked fusiform 

 shape, with long rod-like nuclei, x 400. 



Fig. 9. A view of the same section as fig. 8, slightly displaced. Some contractile fibres 

 belonging to the dilatator muscle have been differentiated out of the iridian epithe- 

 lium. Note the peculiar, almost gelatinous nature of the stroma, still more marked 

 here than in fig. 8. A small piece of the lens-capsule has come into the picture 

 behind the iridian epithelium. ■ 400. 



