PROCESSES OF THE GANGLIOX-CELLS. 301 



become a particularly interesting subject for investiga- 

 tion, inasmuch as the one fibre which supplies the organ 

 has been traced back by Bilharz to a single central gan- 

 glion-cell, which is so large that it can be dissected out 

 with the naked eye. This ganglion-cell has also delicate 

 offsets in other directions, but it has not hitherto been 

 possible to determine their ultimate relations any more 

 than we are able to obtain a definite notion of the minute 

 anatomy of the human brain, and especially to discover, 

 to what extent connections take place there between the 

 different cells. By the investigations which have been 

 instituted into the structure of the spinal cord, it has been 

 shown to be extremely probable, that all- the processes 

 of the individual ganglion-cells do not become continu- 

 ous with nerve-fibres, but that a part of them run to 

 other ganglion-cells and thus establish a communication 

 between the cells. Moreover at certain points, espe- 

 cially in several parts of the surface of the brain, still 

 finer processes are found, which proceed from ganglion- 

 cells and are connected with peculiar, quite characteris- 

 tic apparatuses (bacillar layer of the cerebellum and cere- 

 brum), which offer the greatest resemblance to those in 

 the retina, those extremely delicate, vibratory arrange- 

 ments of the radiating fibres. 



The processes of the ganglion cells might therefore, I 

 think, be divided into three categories ; genuine nerve- 

 processes, ganglion-processes, and those of which the im- 

 port is entirely unknown and which, it would seem, are 

 connected with peculiar and altogether specific appara- 

 tuses, concerning which it is for the present uncertain, 

 whether they are to be regarded as the terminations of 

 the nerves, or only as structures placed in apposition to 

 them. 



