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FREDA BAGE. 
four or five showing in each section at long distances from 
one another. 
(3) Inner Molecular Layer (numbered S in figs. 2, 
4,11,12). 
This is composed, as usual, of masses of fibrillse, the trans- 
verse sections of which give the characteristic punctate 
appearance seen in sections (tigs. 11 and 12, S). This layer 
is present throughout the retina proper, decreasing gradually 
in thickness towards the ora serrata, where it ceases. In the 
fovea centralis (fig. 2, f.c.) it diminishes to about two 
thirds of the thickness which it has over the general part of 
the retina. 
(4) Inner Nuclear Layer (numbered 4 hi figs. 2, 4, 11). 
This layer, in thickness usually about the same as the 
inner molecular layer, contains numerous deeply staining 
nuclei of three kinds, easily distinguishable from one another 
by their size, shape, and staining properties. All three kinds 
are commonly seen in this layer (Quain, 32 ). 
(a) Spherical nuclei which stain very deeply (figs. 4, 
11, n.b.). These are present in by far the greatest numbers, 
and are the nuclei of bipolar nerve-cells. In a few cases their 
attached fibres can be seen. 
(b) Much larger spherical nuclei which stain less 
deeply and belong to multipolar nerve-cells (figs. 4, 11, n.m.). 
(c) Oval nuclei about the size of (a) (figs. 4, 11, n.m.f.). 
They take the stain very deeply, and are always placed with 
their length at l-ijfht angles to the surface of the retina. 
These are the nuclei of the supporting Muller’s fibres (m./.) 
in which they lie. 
Over most of the retina the inner nuclear layer is from 
36-40 /x in thickness, gradually decreasing towards the ora 
serrata. At the macula lutea (figs. 1 and 2) there is an 
enormous increase in the number of cells present, and the 
thickness of the layer becomes rather more than doubled. It 
