Arrangement and Terminations

Since but little work has been done on the innervation of the esophagus, it seemed to me that it might be both interesting and profitable to determine, by means of the inlru-&am 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 esophagus with that of other parts of the alimentary canal. In pursuance of these purposes, I have confined my investigations to the esophagus of the cat and rabbit and have used only the infru-vzium 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 according to whether the staining of the motor or of the sensory apparatus was especially desired, the esophagus was removed and the mucosa with the muscularis mucosz and the submucosa was separated from the underlying muscular coats. When the nerves seemed sufficiently stained, the tissue was fixed, either in a saturated solution of amGonium picrate, as recommended by Dogie1 (g), or, after fixation for a few minutes in the ammo