440 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
layer as being four cells deep in its thickest region. 
Ilesse first showed the incorrectness of these statements. 
In the first place, the cells are of at least two different 
forms, and cannot all be classified as ganglion cells, and 
the so-called outer ganghonic layer of Patten and others 
is really a complex which must be broken up. 
There is a distinct distal cell layer (fig. 29, D.c. l.), 
one cell deep only, extending across the retina against the 
septum. Between these cells and underneath this layer 
are a number of irregularly placed cells, which agree in 
many ways with those between the rod cells. Since their 
function is not known, it is best to drop the term ganghon 
cells, and to call them all interstitial cells; and so there 
are the two groups—outer interstitial cells (fig. 30, 
In. c.o.) underlying and partially penetrating the distal 
cell layer, and inner interstitial cells (Jn. ¢.2.) between 
the rod cells. 
The Distal Cell Layer is a very regular layer of 
roughly triangular cells, the base of which is turned 
towards the septum. ‘The septal surface of these cells is 
drawn out into numerous fine processes almost like cilia, 
which reach up to the septum, so that in sections across 
the retina a cilia-like border appears between the septum 
and the retinal cells. They appear almost like numerous 
nerve fibrils in connection with the optic nerve, and make 
the task of following the real nerve fibrils in this region 
very difficult. The apex of the cell is drawn out and, 
according to Schreiner, becomes dendritic, sending 
delicate fibrils ramifying between the interstitial cells and 
rod cells. In the gold preparations these nerve fibrils 
appeared as a very complete network, and their number 
adds again to the task of examining their connections. 
Schreiner stated that the epithelial distal cells were 
in direct connection with the outer optic nerve by means 
