3 o8 



[Chap. XXXIX. 



a. 



CHAPTER XXXIX. 



THE RETINA. 



434. THE retina (Fig. 157) consists of the following 

 layers, counting from inwards towards the choroid mem- 

 brane: (1) The 

 membrana limitans 

 interna, which is 

 next to the mem- 

 brana hyaloidea of 

 the vitreous body ; 

 (2) the nerve-fibre 

 layer; (3) the layer 

 of. ganglion cells; 

 (4) the inner gran- 

 ular or inner mole- 

 cular layer; (5) the 

 layer of inner 

 nuclei ; (6) the 

 outer granular, or 

 outer molecular, or 

 internuclear layer ; 

 (7) the layer of 

 outer nuclei ; (8) 

 the membrana 

 limitans externa ; 

 (9) the layer of 

 rods and cones ; 

 and (10) the pig- 

 mented epithelium 

 of the retina, or the tapetum nigrum mentioned above, 

 which forms, at the same time, the inner lining epithe^ 

 Uum of the choroid membrane. 



Tig. 157. Irom a Transverse Section 

 through the Eye of Sheep; Peripheral 

 Portion of Eetina. 



a, The inner part of the sclerotic 6, the supra- 

 rhoroidal 'piemen ted) lamellae ; !, d, the layers 

 " choroid coat ; e, the pigmented epithe- 



of the 



lium of the retina ; f, the layer of rods ; ~g, the 

 cones ; h, the layer of outer nuclei ; i, the outer 

 molecular layer; j, the layer of inner nuclei; 

 k, the inner molecular layer ; i, the layer of 

 panglion cells, with the radial or Muller's 

 fibres between ; m, the layer of nerve-fibres. 

 (Atlas.) 



