FINER STRUCTURE OF SYNAPSE 129 



the last on the basis of his investigations accepted his doctrine 

 of double interneuronal continuity. According to Held, the 

 pericellular ends of axis-cylinders are characterized by the loos- 

 ening of their axospongium and the densely embedded 'neuro- 

 somes' and the so constituted axis-cylinder-ends ('Achsencylin- 

 derendflache') are connected with the protoplasm of the nerve 

 cell, which is covered by them, so closely, that there exists no 

 contact but a continuity between the two. Moreover, Held 

 assumed that the different axis-cylinders, which enter together 

 in the nervous cover of a ganglion cell, do not lie isolated side 

 by side, but are combined into a continuous net-work, which he 

 called the pericellular nervous terminal net (perizellulare ner- 

 vose Terminalnetze'). He believed that also by means of Golgi's 

 method he could obtain this 'pericellular terminal net,' which 

 covers widely the cell-body as well as its processes and seemed to 

 receive numerous axis-cylinders to its beams. When Held ('97; 

 17) demonstrated for the first time this silver-impregnated mesh, 

 he identified it at first with the Golgi net, which Golgi produced 

 with the same technic and interpreted as a neurokeratin cover 

 of the nerve cell. Later on (17) he changed his opinion and 

 then considered the Golgi net as not identical with his nervous 

 net. He asserted that the 'Golgi net,' which was demonstrated 

 by Golgi, Semi Meyer, and then by Bethe, was probably not of 

 a nervous nature and denied the direct connection of this net- 

 work with the nervous elements. On the contrary, he was of the 

 opinion that two kinds of net-work — the Golgi net and the peri- 

 cellular nervous terminal net — occupy the surface of the nerve 

 cell, and that alternately. He transferred his 'neurosome-con- 

 glomerations' into the mesh of the Golgi's net and claimed to 

 have found that these conglomerations are connected into a net- 

 work by minute anastomosing bridges, which extend between 

 them, over or beneath the beams of the Golgi net. He also fig- 

 ured the direct connection of the axis-cylinders with these neuro- 

 some-conglomerations. As regards the formation described by 

 Auerbach, Held assumed that he observed the same structure. 

 Ramon y Cajal ('03, 12) summed up the results of his inves- 



