STUDIES 0^ THE XEUEOGLIA. 



BY 



G. CARL HUBER, M. D. 



From the Anatomical Laboratory of the University of Jlichigan. 



Our present conception of the structure of neurogiiar tissue is based 

 in the main on results obtained by the employment of two funda- 

 mentally different methods, each of which is regarded by its supporters 

 as a differential stain for neuroglia. We refer here to the chrome- 

 silver method of Golgi, for many years the only method at our 

 disposal by means of which the structural elements of this tissue could 

 be brought to light. To this method we are indebted for the results 

 obtained by Golgi, v. Lenhossek, v. Kolliker, Ramon y Cajal, Retzius, 

 Sala y Pons, Van Gehuchten, Eurich, Reinke and others in their inves- 

 tigations of the structure and histogenesis of the neuroglia. The other 

 method was the one fully described by Weigert in 1895 in his large 

 monograph on the structure of neurogiiar tissue, giving the results of 

 seven years' labor in this field. Almost simultaneously appeared Mal- 

 lory's publication giving an analogous method. In the Weigert and 

 Mallory methods, the staining is the result of a chemical differentiation 

 of the neuroglia fibers. Their results have been corroborated by Pol- 

 lack, Ivrause and Aguerre working with normal tissues and by Taylor, 

 Storch and Bonome in their study of pathological tissue and new 

 growths. Quite recently Benda has published a differential stain for 

 neuroglia, which seems destined to become very useful. 



All recent writers on neurogiiar tissue have called attention to the 

 apparently contradictory results obtained by those observers working 

 with the chrome-silver method as compared with the recorded observa- 

 tions of investigators who have used the more modern differential 

 stains, and a glance at the more recent literature is sufficient to con- 

 vince one that a classification of the current views of the structure of 

 neurogiiar tissue may with propriety be based on the methods used in 

 the investigation of the tissue. It is, however, not our purpose at the 

 present time to extend this controversy, and a repetition of what has 

 been previously stated in several of the discussions of neuroglia litera- 

 ture seems uncalled for; it Avill therefore be entered upon only to the 

 extent necessary to present our own observations as clearly and suc- 

 cinctly as possible. 



