178 STRUCTURE OF THE NERVOUS SYSTEM, BY MAX SCHULTZE. 



glion cell, however numerous its processes may be, only one 

 peripherically coursing axis cylinder arises. This runs without 

 branching, obtains, sooner or later, a medullary sheath, and 

 passes into one of the roots of the nerves. It possesses a 

 iibrillar structure, as I have myself most distinctly seen, both 

 in sensory and motor and ganglion cells. The other processes 

 of these ganglion cells, the number of which is greater in the 

 large cells of the anterior horns than in those of the posterior, 

 branch in an arborescent manner very soon after their origin. 

 Their structure is also distinctly fibrillar ; but the quantity of 

 interfibrillar granular substance they contain is greater than in 

 the axis-cylinder process. The fine filaments (primitive fibrils), 

 which result from their ramification, soon evade observation, 

 and their ultimate destination is unknown. Deiters believes 

 that in some few instances he has observed them to become 

 invested with a delicate medullary sheath. 



The fibrils of both kinds of processes arise from the gan- 

 glion cell substance itself, which exhibits a fibrillar structure 

 throughout, though a finely granular substance, often contain- 

 ing yellowish or yellowish-brown pigment, also exists be- 

 tween the fibrils ; this may extend into the branched processes, 

 or after being interrupted for a greater or less extent, may 

 again make its appearance in them. The fibrillar structure 

 may be most distinctly perceived in the cortical portion of 

 the ganglion cells, though it unquestionably extends into the 

 interior. In many cases, and especially in young rather than 

 in more fully developed ganglion cells, a considerable quantity 

 of finely granular material appears to occupy the interior of 

 the cell, and to surround the nucleus. The course of the fibrils 

 within the ganglion cells is very complicated ; they may be 

 seen passing from the processes into the cell substance in a 

 divergent manner in every direction, and are there lost in the 

 confused whorl of decussating filaments. This structure exists 

 in the perfectly fresh state, as may be seen in the large cells of 

 the fresh spinal cord which have been isolated after the addi- 

 tion of serum, and is very distinct in preparations macerated in 

 perosmic acid and other hardening agents, which either check 

 the natural conversion of the fibrils after death into a granular 

 mass, or which do not produce any granular coagulation. 



