158 KIYOYASU MARUI 



SUMMARY 



1. In the 'axone cap' and on the surface of Mauthner's cell a 

 Golgi net structure was very distinctly demonstrated by means 

 of Levaditi's method; in Heidenhain and other preparations a 

 similar net-work was brought out. The Golgi net is of glious 

 nature and is in close relation to the nervous elements in the 

 synapse. According to the results of this study, the unmedul- 

 lated parts of the nerve fibers are also enveloped in a sheath of 

 glious tissue; the finer structure of this glia sheath is as yet un- 

 known. 



2. The hypothesis of Held concerning the existence of- two 

 kinds of net-work on the cell surface — a Golgi net and a 'peri- 

 cellular nervous terminal net' — is denied; there exists, as far as 

 my observations go, only one net structure, which is formed by 

 both the nervous and the glious tissues. The so-called pericel- 

 lular nervous terminal net is not to be regarded as a real nervous 

 net-work, but to be considered as a picture produced by the 

 simultaneous stain of the Golgi net-work. 



3. The contact theory is a histological impossibility. The 

 terminal feet cannot be regaMed as the specific contact organs, 

 but as the points in the course of axone fibers, where the dissolu- 

 tion of fibers takes place. The continuity of the intra- and 

 extracellular neurofibrils is very clearly demonstrated. 



4. The intracellular neurofibrils do not form any reticulum in 

 Mauthner's cell; nor did the net structure which was described 

 by many authors in other animals, ever come to my observation 

 in the nervous terminal feet. The nerve fibers showed merely a 

 splitting into numerous delicate fibrils in them. 



