156 KIYOYASU MARUI 



ever, who took for granted that here the dissolution of the nerve 

 fibers occurs as a consequence of the loss of the perifibrillar 

 cement substance, I cannot agree. On the contrary, I assume 

 that the dissolution of the fibers is to be regarded as the result 

 of the accumulation of the perifibrillar neuroplasm. 



Bartelmez (4) described in the 'axone cap' of Mauthner's 

 cell two kinds of endings — 'free endings' and 'knob endings,' 

 which latter are in contact with the cell surface; besides these he 

 mentioned on the lateral dendrite 'club endings.' As far as my 

 investigation went, the 'free endings' of Bartelmez are very 

 hard to accept; though I found in my preparations nerve fibers 

 which do not reach to the cell surface, it is always probable that 

 they appeared in section. Nor can I find any essential difference 

 between the endings in the 'axone cap' andin the lateral dendrite, 

 as already described. Moreover, he did not state the structure 

 of these endings in detail; he figured as 'pericellular net' (figs. 

 12, 13) a minute solid or ring-shaped structure, which is perhaps 

 identical with the ring-shaped ending apparatus described by 

 Cajal. Above all I must emphasize that I found the neurofi- 

 bril continuity on the cell surface as well as on the dendrites; 

 the 'plasma membrane,' which Bartelmez described on the sur- 

 face of his club endings, must not be regarded as the last end 

 of the nerve fibers. 



Held (18) assumed a 'pericellular nervous terminal net,' which 

 exists on the cell surface alternating with the Golgi net, as re- 

 marked before. In the previous chapter I showed that there is 

 only one net-work on the cell surface formed by both the Golgi 

 net and the nervous elements. Now, in my Cajal preparations, 

 which do not show the Golgi net substance, I was not able to 

 find any net-work in the synapse. I showed that Held's figures 

 of his neurosome and Golgi preparations do not argue for his 

 hypothesis. It appears extremely interesting to me that in his 

 Cajal preparations the deeply stained terminal feet are not at 

 all (19) connected by bridges or at the most connected among 

 each other by feebly (20) stained bridges. Moreover, it must 

 be remembered here that in the neurosome preparations of Held 



