220 THE RETINA, BY MAX SCHULTZE. 



The retina is composed of several layers, the synonyms of 

 which threaten to perplex ophthalmological literature. It is 

 therefore of importance to name the various layers in the sim- 

 plest manner possible. The terms employed by Heinrich Muller 

 in all his publications upon the retina have proved the most 

 serviceable, and with a few modifications may still be retained. 

 The only terms I have introduced are my membrana limitans 

 externa and the division of the intergranule layer of H. Muller 

 into two layers. I indeed first called attention to the necessity 

 of making this division, and whilst preserving the name of 

 intergranule layer to that constantly present layer of finely 

 granulated substance which lies between the internal and 

 external granules, have dissociated from it that portion of the 

 external granule ]ayer composed of the rod and cone fibres, 

 which is particularly strongly developed at the yellow spot 

 in Man, and which was included by Muller (1) in his inter- 

 granule layer. Henle calls the intergranule layer, as I 

 define it, the external granulated layer, and thus expresses 

 its similarity in structure with the molecular or internal 

 granulated layer ; the radially fibrillated division of the ex- 

 ternal granule layer, on the other hand, he terms the outer 

 fibrous layer. In order to obviate misapprehension in the ex- 

 planation of the name intergranule layer, which, it will be seen 

 from the above, in consequence of H. M tiller's publications, differs 

 somewhat from mine, we shall hereafter term it Henle's exter- 

 nal granulated layer instead of the " intergranule layer." In 

 accordance with the nomenclature here employed, the layers of 

 the retina from within outwards are as follows : 



1. Membrana limitans interna. 



2. Optic-fibre layer. 



3. Ganglion-cell layer. 



4. Internal granulated (molecular) layer. 



5. Internal granule layer. 



6. External granulated (intergranule) -layer. 



7. External granule layer, including the external fibre layer, 



which is present in certain parts of the retina. 



8. Membrana limitans externa. 



9. Layer of rods and cones. 

 10. Pigment layer. 



