PLATE 1 



EXPLANATION OF FIGURES 



1 Approximately transverse section of right eye. Dorsal side up. Dark 

 adapted (?). X 1500 



2 Nearly transverse section of left eye. Dorsal side up. The mate of eye 

 shown in figure one. Dark adapted. X 1500 



3 Transverse section of left eye. Dorsal side up. Dark adapted. X 1500 



4 Transverse section of right eye. Dorsal side up. Dark adapted. X 1500 



5 Frontal section of left eye. Anterior end up. Dark adapted. X 1500 



6 Nearly frontal section of right eye. Anterior end up. Dark adapted. 

 X 1500 



7 Nearly frontal section of left eye. Anterior end up. Dark adapted eye. 

 X 1500 



8 Nearly frontal section of left eye. Anterior end up. Dark adapted eye. 

 X 1500 



9 Nearly frontal section of right eye. Anterior end up. Light adapted eye. 

 X 1500 



10 Approximately frontal section of right eye. Anterior end up. Light 

 adapted eye. X 1500 



11 Nearly frontal section of left eye. Anterior end up. Light adapted eye. 

 X 1500 



12 Nearly frontal section of right eye. Anterior end up. Light adapted eye. 

 X 1500 



530 



