328 
FREDA BAGE. 
Fig. 9. — Tangential section of portion of tlie cone-layer to show the 
arrangement of double and single cones and their structural detail, 
(e), (/), (g), (h) and (j) are various double cones referred to in the text. 
Preparation as for fig. 2. X 1120. 
Fig. 10. — Tangential section through the outer nuclear layer at the 
level of the nuclei of the cone-cells. From an eye fixed in acetic 
bichromate and stained on the slide with Ehrlich’s hsematoxylin. 
X 1120. 
PLATE 29. 
[All the figures are from drawings or preparations of the retina of 
Sphenodon pu net at us, and they have been outlined by camera 
lucida.] 
Fig. 11. — Vertical section of portions of the inner molecular and 
inner nuclear layers. The three kinds of cells which are present in the 
inner nuclear layer are distinguishable by the size and shape of their 
nuclei. Staining as for fig. 6. x 1120. 
Fig. 12. — Portion of vertical section of the nerve-fibre, ganglion-cell 
and inner molecular layers, to show the arrangement of the nerve-fibres 
in bundles and their position and that of the ganglion-cells. The 
figure also shows the trumpet-shaped bases of Muller’s fibres which 
support the retina. Staining as for fig. 6. X 560. 
Fig. 13. — Vertical section of the retina at the ora serrata, showing 
the transition between the various layers of the retina proper and the 
columnar epithelial cells of the pars ciliaris retinse. The pigment 
layer had been pulled away in the preparation and has been partly 
restored. Staining as for fig. 6. x 560. 
Fig. 14. — Tangential section through the outer portions of several 
pigment epithelial cells, showing their hexagonal and pentagonal shapes, 
and the arrangement of the protoplasm in blocks. Staining as for fig. 
3. x 1120. 
