276 KIYOYASU MARUI 



always indicate the previous existence of amoeboid glia cells. In 

 the present work all the fish brains, both normal and fatigue, were 

 placed in the fixing solutions in their fresh condition, and the like- 

 lihood of postmortem production of the amoeboid glia cells cannot 

 at all come under consideration. Attention must especially be 

 called to the fact that in all my control preparations not a single 

 amoeboid glia cell did come to my observation in and about the 

 synapse. 



What would then be the mechanism of the breaking up of the 

 glia reticulum? It is very hard to answer this question definitely. 

 Eisath (10), who studied and demonstrated the protoplasmatic glia 

 structure very well by his own method, suggested that in the sec- 

 tions in which amoeboid glia cells occurred either in the marrow 

 only or in both the marrow and the cortex, the glia cells with deli- 

 cately arborized protoplasm processes do not come to observation. 

 Alzheimer (1) also made the same observation; instead of the glia 

 cells wdth arborized protoplasm processes, he found by means 

 of the same method glia cells with a little increased plasm with- 

 out any process or those with large cell body carrying different 

 kinds of granules. He took for granted that with the appearance 

 of the amoeboid glia cells the other glia structure also sustain 

 some alteration. On another occasion Alzheimer (1) made the 

 observation that in a cortex, which showed no glia cells with pro- 

 toplasmatic processes by means of Mallory's method, the. Golgi 

 method revealed such cells with processes. On the ground of 

 this finding, he carefully expressed his opinion, declaring that the 

 processes did not here go into decay or were not withdrawn by 

 the cells, but merely did not show the affinity to Mallory's 

 hematoxylin. 



Now, as already remarked, the processes of the glia cells of the 

 synapse arborize and unite into a uniform glia reticulum in the 

 synapse. This condition can be beautifully demonstrated in the 

 Levaditi preparations. In fatigue a number of the glia cells are 

 converted into the amoeboid glia cells and they lie free from the 

 reticular structure of neuroglia tissue; and in this case attention 

 must be called to the fact that some other glia cells in the synapse 

 still show their relation to the reticulum and that I could observe 



