278 THE RETIXA, BY MAX SCHULTZE. 



Iwanoff, taken from a human retina, macerated by suppurative 

 inflammation,* in which the nervous elements were collectively 

 destroyed, whilst the supporting framework alone remained, 

 exhibits similar appearances. 



This fibrous basketwork, which is isolable in the above - 

 desciibed 'mode, appears to be present in all Vertebrata, as 

 well as in Man. Further researches, however, are required to 

 show how far it is prolonged over the surface of the outer 

 segments.f 



Besides the nuclei which ^are present within the internal granule 

 layer in the radial supporting fibres, others are found, though for the 

 most part more sparingly distributed in other layers of the retina, and 

 especially in the two molecular layers.} The importance of these 

 increases in those pathological processes which advance pari passu 

 with an increase of the cells of the connective tissue. Even if the 

 statements respecting a proliferation of these cells by fission are to be 

 admitted with caution, it may nevertheless be regarded as established 

 that under certain circumstances a finely or coarsely granular proto- 

 plasm containing fat molecules, collects around the pale oval nuclei of 

 the connective substance, and that the number of these cells can 

 augment materially in excess of all that we know of them in their 

 normal state. Fatty degeneration of the retina does not limit itself to 

 the immediate neighbourhood of the nuclei of the connecting substance, 

 but may also, as for example in morbus Brightii, occur in the form of 

 delicate rows of granules along the whole length of the supporting 

 fibres, especially towards the inner layers of the retina, so that these 

 fibres might be imagined to be hollow. In the external granule layer, 

 also, I have observed cells that have undergone fatty degeneration, and 

 which from the characters of their nuclei I must regard as elements of 

 the connecting substance, so that it is impossible to deny the presence 

 of nuclei of the connective substance under normal conditions in the 

 external granule layer, however closely its nervous cells are compressed 

 together. It is a matter of importance in regard to the question of 

 the origin of those tumours of the retina that have been termed 



* Grafe's Archiv, Band xv., Abtheil ii., Plate ii., fig. 2. 



t In an essay published in the 7th Vol. of the Archiv fur Mikroskop. 

 Anatomie, p. 81, E. Landolt maintains, on the ground of his personal 

 observation, that in Amphibia the outer segments of the rods and cones 

 lie in a sheath belonging to the supporting connective substance. 



$ See inter alias Nagel in Grafe's Archiv, Band vi. , p. 218. 



