FINER STRUCTURE OF SYNAPSE 147 



Also the hypothesis of Bethe (7) who considered it as the nervous 

 structure, I should deny positively with Held (18, 21), Economo 

 (15), and others. Held discovered in both the white and gray 

 matter of the brain a glia reticulum which provides myelin 

 fibers with neuroglia sheaths and he identified this with the 

 'Fiillnetz' of Bethe;. he also demonstrated that the beams of 

 the glia reticulum pass into those of the Golgi net, increasing 

 thereby the density of its substance. Afterwards he added his 

 further observation that the neuroglia cells accompanying the 

 ganglion , cells form the Golgi net of the latter. Economo found 

 the direct connection between the Golgi net beams and the glia 

 nucleus by pediform appendages. All these findings I could es- 

 tablish in the synapse of Mauthner's cell; there is no doubt now 

 that the Golgi net is of glious nature ; it must be added here that 

 also Schiefferdecker,^ Paladino (26), Besta,*^ and Alzheimer 

 admitted its glious nature. 



What, then, is the relation between the nervous elements and 

 the Golgi net structure? As I remarked already, the myelin fibers 

 are enclosed in glia sheaths of^ net-like structure, which is con- 

 tinuous with the diffuse glia reticulum. As far as I know, the 

 relation of the unmedullated part of the nerve fibers to the glia 

 tissue is not known very clearly. Held (19) said that, only oc- 

 casionally and rather unevenly by means of Bethe' s molybden 

 technic, he obtained pictures in which the unmedullated fibers 

 are enveloped in a delicate Golgi net. He added also that these 

 sheaths of unmedullated nerve fibers are connected with the 

 diffuse delicate glia reticulum by means of projecting spikes. 

 This description of Held comes pretty near to my own findings 

 in this work (nerve fibers in the beams of the Golgi net, cross- 

 sections of nerve fibers at the nodal points of the net-work), 

 which indicate that the unmedullated part of the nerve fiber is 

 also enclosed in glia sheaths. I am very sorry that I could not 

 establish the finer structure of these glia sheaths in the present 



* Heidenhain, Plasma u. Zelle, Bd. 1, a, p. 911. 

 ^ Riv. di. patol. nerv. e ment., T. 16, p. 604. 

 7 Nissl's Arbeiten, Bd. 3. 3, p. 412-421. 



