THE INTRINSIC PULMONARY NERVES BY THE 

 SILVER METHOD. 



[Abstract Paper.] 



( With Plate XIV.) 



From the Patholgical Laboratoty of the Johns Hopkins Univer- 

 sity and Hospital. 



By Henry J. Berkley, M.D., Baltimore. 



Little information, from either histological text books or 

 recent monographs, is to be found concerning the final distribu- 

 tion of pulmonary nerves. Krause^ apparently gives the entire 

 knowledge on the subject in the following words: "The pul- 

 monary nerves course with the bronchi, and contain many pale 

 nucleated as well as double contoured fibres, and have clusters 

 of ganglion cells among the filaments. The first named fibres 

 are distributed to the smooth muscular cells, the dark contoured 

 to the mucous membrane of the bronchi. Their terminations 

 are not known." 



By the older methods of preparation with osmic, acetic, or 

 chromic acids, it was more than difficult to obtain positive re- 

 sults beyond those already stated by Krause ; even in prepara- 

 tions of the lung treated according to the Weigert hematoxylin 

 methods little can be determined concerning the double con- 

 toured fibres (and of course nothing of the sympathetic ones), 

 owing to the lung tissues decolorizing very slowly in the borax 

 and ferricyanide of potassium solution. 



For the purpose of this experiment the gray rat was al- 

 most entirely used, the fibres staining better in it than in 

 other animals, and the methods of fixation and staining were 

 the same as used in our recent investigation on the hepatic 

 nerves, namely, the rapid Golgi, and its modification the picric- 

 acid-osmium-bichromate method. The latter gave incomparably 

 finer results. 



The pulmonary nerves in general present some slight dif- 



lAllg. Anatomic, 1876. 



