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1. As is well known, the very large nerve-cells ("KolossaJzellen") 

 lying at about equal distances from each oilier in the axis of the 

 spinal cord, possess a thick axonic fibre, that after leaving the cell-body 

 describes a characteristic curve and passes into one of the colossal 

 nerve-fibres that run in a longitudinal direction through the spinal 

 cord, and a number of dendrites, springing from the cell-body at 

 different points. 



Sections of these cells, stained after the method of Bielschowsky, 

 give a very clear picture of the neurofibrillar structure. In a section 

 in which only some of the dendrites are to be seen, and not the 

 axonic fibre with its "cone d'entrance" (of which more later on) 

 these cells show an arrangement of the neurofibrillae as shown in 



% 1- 



The cell is surrounded by a glious capsule, composed of line 

 interwoven fibrillae. The preservation of the nervous system in formol, 

 necessary for the BiELScHOWsKY-reaction. causes the cells to shrink a 

 little, so that the pericellular cavity i> larger than it is in normal 

 life and in well-preserved specimens. Within the cell-body the 

 neurofibrillae form a very distinct and regular network. Everywhere 

 they anastomose with each other, nowhere I could discover free 

 running fibres. The meshes are regular, round or manysided, and 

 nearly all of about the same size. A subperipheral zone is formed, 

 where the meshes are somewhat smaller and the composing neuro- 

 fibrillae a little coarser. From this zone a few coarse neurofibrillae may 

 be followed in the network radiating to the central zone around the 

 nucleus. The nucleus itself is not coloured in these preparations, but 

 is only to be seen as a clear round or oval spot in the midst of the 

 darkly stained network of the neurofibrillae. There where a dendrite 

 leaves the cell-body, the meshes of the network are elongated in the 

 direction of the processus (fig. J, 46, 6). In the dendrites themselves, 

 at least in the coarser ones, the anastomosing of the neurofibrillae 

 is to be seen still at some distance from the cell-body. In tig. 1 is 

 drawn a section of 7 ,« thick In three of the following sections, 

 passing through the dendrites, whose origin is shown in fig. 1, I 

 could still see the anastomosing of the composing neurofibrillae. In 

 fig. 2 is drawn one of the large dendrites of a similar colossal cell 

 there where it branches into two. The network of the neurofibrillae, 

 several coarser (and more darkly stained) fibrillae, and the continuity 

 of the network in both branches is clearly to be seen. In the finer 

 dendrites the neurofibrillae seem to become isolated sooner after 

 having left the cell-body (fig. 1 at b). The same is to be seen in the 

 smaller nerve-cells of the spinal cord (figs, ib, 6). 



