THE EYE 



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processes of the cells of the pigment layer. The fibre ends of 

 the rods and cones project toward the centre of the eye. 2. 

 The bipolar cells of the second layer are short nerve cells which 

 end at either extremity in a tuft of branches. They seem to 

 connect the first and third layers. 3. The ganglion cells of the 



Fig. 81. — Diagram showing some of the retinal elements. Layer i is 

 nearest the centre of the eye and consists of nerve fibres (/) which enter the 

 optic nerve at the blind spot; 2, the ganglionic-cell layer, made up of nerve 

 cells from which the fibres (/) arise; 3, the inner molecular layer made up of 

 the minute branches arising from the cells of layers 2 and 4; 4, the inner nuclear 

 layer, containing the nuclei of the short elements which connect layers 3 and 5; 

 5, the outer molecular layer which is similar to layer 3; 6, the outer nuclear layer 

 — contains the nuclei of the rod and cone elements; 7, the layer of rods (r) and cones 

 (c); 8, the pigment layer. The rods and cones are the sensory elements. They 

 project into the pigment layer. (From Galloway.) 



third layer are large cells with a bush of protoplasmic processes 

 and a long fibre. The fibres form a layer on the surface of the 

 retina next the centre of the eye. They all converge to the 

 point where the optic nerve enters the eye. It is these tibrcs 

 with their medullary sheaths that constitute the optic nerve. 



