Explanation of Figures. 



List of Abbreviations. 



n, 11^ n'-. Optic nerve and its l^ranclies. 

 p. l^ig'uient layer. 



ret. Metina. 



ro. Rod. 



s. Triangular screen. 



t. TaiJetum 



i'^i'^- 1. Iiilialoiit siplioii ofCV//7//i/»/ )iiiiticiiiii, iniigmûed. One longitudinal half uf 



it is c\it away. 

 Fig. 'I. Median sagittal section of a tally developed eye (constructed from two 



sections). 

 Fios. 3-7, S(3nii-diagrammatic representations to illustrate the less abbreviated 



process of the development of the eye (sagittal sections). 

 J^'i'ts. b-10. Semi-diagrammatic representations to illustrate the more abbreviated 



process of the development of the eye (longitudinal sections). 



