mollgaard's reticulum 319 



wahrscheinlich gemacht, dass die Nissl-Korner von diesen Netzen 

 gebildet werdeii." The origin and nature of the network dis- 

 cussed now becomes Mollgaard's principal question. For the 

 purposes of the present paper, however, it is not necessary to 

 follow him through all the details of his attempts to explain its 

 presence. But it might be added that his final conclusion regard- 

 ing its nature is that it is a 'glia-network/ which is both inter- 

 cellular and intracellular. 



Secondly, regarding the neurofibrillae, Mollgaard's conclusion 

 is evident from the following quotations: 



Ich habe nun gleichzeitig an vital alkoholfixierten Schnitten die all- 

 gemeinen Fibrillmethoden versucht, doch iiberall mit negativem Ergeb- 



nis Auf Grund dieser Versuche darf ich nicht wagen, 



die Existenz der Neurofibrillen zu verneinen. Dazu scheint mir, dass 

 ich die Verhaltnisse vorlaufig zu wenig untersucht habe. Doch kommt 

 mir unleugbar vor, dass die ebenerwahnten negativen Ergebnisse recht 



stark gegen die Existenz der Neurofibrillen sprechen 



Falls dagegen Neurofibrillen Kunstprodukte gleichwie Nissl-Korner sind, 

 so wiirden diese vermutlich ganz dasselbe Schicksal wie die Nissl-Korner 

 erleiden, namlich dass sie erscheinen, wenn man langsam fixiert und 

 die postmortalen Prozesse ausgeschlossen sind, d. h. wenn man das 

 Gewebe vital fixiert. 



It may be further noted that he remarks: ''Die Zellen lassen 

 sich iiberhaubt sehr schwierig impragnieren." He is of course 

 speaking of cells 'vitally-fixed.' In speaking of the neurofibrillae 

 he also says that one cannot deny that the appearances which 

 the 'vitally-fixed' nerve cells present lie nearest to the reality; 

 and so one can maintain with considerable certainty that what 

 is not present in the 'vitally-fixed' nerve cell is likewise not pres- 

 ent in the living cell. 



Retzius ('11) strongly criticises Mollgaard for adopting a 

 method which in all its essentials is like that which he and Axel 

 Key discarded thirty-seven years ago. He says that Mollgaard 

 without doubt started out with the right object in view, namely, 

 to secure a simple method for the study of the central nervous 

 system, realizing that our present methods demand too much 

 preparation before the tissue is ready for study. But of the 

 methods for the study of the central nervous system, Retzius 



THE JOURNAL OP COMPARATIVE NEOROLOGY, VOL. 23, NO. 4 



