ARRANGEMENT AND TERMINATIONS OF NERVES 

 IN THE CESOPHAGUS OF MAMMALIA. 



By Lydia M. DeWitt, B.S., M.D,, 



Assistant in Histology, University of Michigan, Ann Arbor. 

 With Plate XXVI. 



Since but little work has been done on the innervation of 

 the oesophagus, it seemed to me that it might be both interest- 

 ing and profitable to determine, by means of the intra-vitam 

 methylene blue method, the arrangement and terminations of 

 the nerves in this part of the digestive tract, to verify the results 

 already gained by other methods and, so far as practicable, to 

 compare the innervation of the oesophagus with that of other 

 parts of the alimentary canal. 



In pursuance of these purposes, I have confined my inves- 

 tigations to the oesophagus of the cat and rabbit and have used 

 only the intra-vitam methylene blue method. In most cases, I 

 injected into the thoracic aorta, proximal to the arch, a i ^ 

 solution of methylene blue in normal salt solution, the quantity 

 varying with the size of the animal and the special purpose to 

 be attained. When necessary, the carotids at the level of the 

 thyroid cartilage and the aorta just above the diaphragm were 

 ligated before the injection was made. After a time varying ac- 

 cording to whether the staining of the motor or of the sensory 

 apparatus was especially desired, the oesophagus was removed and 

 the mucosa with the muscularis mucosae and thesubmucosa was 

 separated from the underlying muscular coats. When the nerves 

 seemed sufficiently stained, the tissue was fixed, either in a sat- 

 urated solution of ammonium picrate, as recommended by 

 Dogiel (9), or, after fixation for a few minutes in the ammo- 

 nium picrate solution, was removed to the \o% solution of 



