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layer as being four cells deep in its tliickest region. 

 Hesse first showed tlie 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 ganglionic 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. /.), 

 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 ganglion 

 cells, and to call them all interstitial cells ; and so there 

 are the two grou]Js~outer interstitial cells (fig. 30, 

 In. c. o.) underlying and partially penetrating the distal 

 cell layer, and iuneT- interstitial cells [In. c. i.) 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 numerovis 

 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 jDreparations 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 



