MOLLGAARD'S RETICULUM 



THOMAS J. HELDT 



The Anatomical Laboratory of the University of Missouri 



SIX FIGURES 



Since the appearance of MoUgaard's article: ''Die Vitale Fix- 

 ation des Zentralnervensystems," in the Anatomische Hefte (Bd. 

 43, July, 1911) much comment has been made upon his method 

 and his conclusions. Considerable difference of opinion still 

 seems to exist however regarding his results, so it has been thought 

 profitable to do some further work in this direction. Prominent 

 among MoUgaard's conclusions is the fact that he strongly doubts 

 the existence of Nissl's bodies and neurofibrillae in the Vitally- 

 fixed' nerve cell. Thus, one of the objects of the present paper 

 will be to determine whether or not Nissl's bodies do exist in 

 tissue so fixed, and a few observations incidentally made on 

 neurofibrillae will be included. An endeavor has also been made 

 to ascertain how and why MoUgaard's 'glia-network' in neural 

 tissue is formed during the process of freezing. 



This investigation was undertaken on suggestion of Dr. CM. 

 Jackson by whose criticism and advice the author has greatly 

 profited and for which aid he here expresses his indebtedness. 



■ REVIEW OF RECENT LITERATURE 



Mollgaard ('11a) emphasizes the fact that to exclude the great- 

 est number of artefacts a tissue should, before its study, undergo 

 as little preparation as possible. He remarks, that the very 

 simplest of methods is demanded; and, that with simpler tech- 

 nique comes ease in making controls. If one would succeed, he 

 says, in studying the finest structural relationships of the living 

 cell, one must, firstly, be prepared to study a definite physio- 



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