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of one of the cilia-like fibres, which he illustrated as 

 coining from the middle of the septal surfaces. 



Hesse, in 1900 (32), could not see any connection 

 between the fibres of the optic nerve and the distal cells, 

 but traced the nerve fibres between them to connections 

 with the interstitial cells, which he regarded then as sense 

 cells but not ganglion cells. In a later paper, however 

 (1907), after a study of the very early stages, he shows 

 that the optic nerve is already connected with distal cells 

 before the interstitial cells are in existence. According 

 to him, the nerve fibrils of the outer optic nerve, after 

 boring through the septum, pass between the distal cells 

 and connect to the sides, and not the middle of the septal 

 surface as stated by vSchreiner. The attachment of the 

 outer optic nerve to the distal cells is practically certain, 

 but there is still great doubt about the interstitial cells, 

 and though I could trace their processes to the cilia-like 

 border, there could be no certainty of connections in the 

 confusing mass of fibres. 



The Interstitial Cells are irregular in shape and 

 drawn out into fine branching processes. The outer inter- 

 stitial cells bear processes which pass between the distal 

 cells to the retina surface. The inner interstitial cells are 

 very much flattened, and lie in such close proximity, 

 wrapping as it were round the rod cells, that their nuclei 

 were first taken for the nuclei of these. The cells are 

 rather small, very little larger than the prominent nucleus, 

 and, in addition to processes extending amongst the rod 

 cells, one from each cell penetrates the sieve membrane 

 and lies between the rods. 



The nuclei of the interstitial cells stain very darkly 

 with Haematein, and quite differently to the nuclei of the 

 rod and distal ceils. Hesse, Patten and Schreiner have, 

 regarded the interstitial cells as sense cells. Schneider, 



