Plate XV 



Fig. 73 Detailed representation of pigment area shown in preceding figure. Shows collection of 

 pigment cells within cysts. X 900. 



Fig. 74 Part of section from Cambarus virilis sixty-two and one-half hours after operation. In left 

 part of figure lower part of cone and upper end »f rhabdom. Remainder of figure occupied by chains 

 of abnormal cells apparently developing from disintegrating retinulae. A few cells show pigment gran- 

 ules. X 910. 



Fig. 75 Group of cells which show polymorphic nuclei, a, Group of disintegrating retinulae from 

 Cambarus virilis seventeen and one-half hours after operation; h, group of disintegrating retinulae 

 from Cambarus virilis thirty-nine hours after operation; c, disintegrating retinulae from Cambarus 

 gracilis sixteen days after operation; d, group of abnormal pigment cells from Crangon twenty-three 

 days after operation; e, group of abnormal pigment cells from hermit crab sixty-seven days after opera- 

 tion; /, group of depigmented pigment cells from pigment cyst in eye of stump of Palasmonetes thirty 

 days after operation; g, outline of crushed pigment body lying in same group with depigmented cells 

 shown in /. X 900. 



