Plate XII 



Fig. 60 Group of retinulae from eye shown in Fig. 6. Proximal retinular processes are seen extend- 

 ing to basement membrane. Two of the processes can be traced through below the basement mem- 

 brane. X 900. 



Fig. 61 Taken from section of eye shown in Fig. 16. Shows group of retinulae. Nuclei in out- 

 line and proximal processes shown. X 1350. 



Fig. 62 Group of retinulae from eye shown in Fig. 6. Shows proximal retinular processes pene- 

 trating basement membrane and twining among ganglion cells below. X 1350. 



Fig. 63 Taken from section of eye shown in Fig. 1 1 . Shows earlv stage in differentiation of crystal- 

 line cones. Cone nuclei are being separated from hypodermal nuclei. Hypodermal nuclei are grouped 

 in pairs. Delicate strands of cytoplasm extending inward from pairs of nuclei. X 1350. 



Fig. 64 Taken from section of eye shown in Fig. 11. Shows more advanced stage of cone differen- 

 tiation than Fig. 29. Cell outlines becoming defined but hypodermal and cone cells not distinctly sepa- 

 rated. Section somewhat oblique so that the four cone nuclei are visible. Distal retinular processes 

 extending between the cones. Lower ends of cones not yet differentiated. X 900. 



