536 
PHYSIOLOGY: S. J. MELTZER 
Proc. N. a. S. 
responding ganglion, or of both ganglia, gave results similar to those ob- 
tained before the removal, that is, active respiration, passive respiration 
(inhibition of the diaphragmatic movements), acceleration of the respira- 
tion, or a tetanic standstill of the diaphragm in an inspiratory state, ac- 
cording to the strength of the stimulus used and the individuality of the 
animal. Bloodpressure. — Stimulation of the vagus nerve gave a definite 
rise, and stimulation of the depressor nerve gave a fall. Rise and fall 
after removal of the ganglia were — at least — as good as before the removal. 
Deglutition. — When the animal was not too deeply narcotized, stimula- 
tion of the vagus trunk produced irregularly one deglutition or more, and 
stimulation of the central end of the superior laryngeal nerve produced 
regularly a series of swallows. Sensation. — Finally, it may be added that 
when the animal was nearly out of ether, stimulation with a strong cur- 
rent brought out signs of sensation, which gave the signal for an increase 
of the anesthesia. These experiments show unmistakably that the afferent 
nerve fibres within the vagus were in no visible way affected by the act of 
removing the ganglia. 
The Centrifugal Fibres. — The efferent nerve fibres of the vagus, which 
concern us here, are those which innervate the muscles of the larynx, the 
pharyngeal muscles and the muscular fibres of the esophagus. The lar- 
yngeal innervation after removal of the ganglia has not yet been studied. 
However, clear evidence was obtained that the motor nerve fibres attend- 
ing the pharynx and the esophagus were functioning in a normal way. 
Under moderate anesthesia the inferior pharyngeal muscles were seen to con- 
tract with the rise of the larynx, which accompanies the initial stage of degu- 
tion, and the rise was followed by a normal peristaltic wave in the esophagus. 
The condition of the esophagus at the autopsy is another evidence that 
the vagus was not affected by the procedure of the removing of both 
ganglia. In the autopsies made on the twenty-five rabbits which died 
after the removal of both ganglia, the esophagus was found empty and 
contracted in fourteen cases; in the other cases the condition of the 
esophagus was not noted. In other words, in all the cases in which the 
esophagus was examined, it was found that after removal of the ganglia 
this tube was empty and contracted. On the other hand, in a series of 
eighteen rabbits in which both vagi were cut and in which nearly all 
animals died in less than twenty-four hours, at the autopsy the esophagus 
was found distended and filled with food in its entire length in thirteen 
animals; in the remaining five the esophagus was either only partly filled 
or entirely empty but was not exactly contracted. I wish to point out 
here that the upper part of the esophagus is partly innervated b}^ pharyn- 
geal nerves which remain intact when both vagi are cut in the neck. 
Moreover, food may be driven out by the rigor of the esophagus which, 
after the rigor passes away, may be relaxed again. At any rate, it is a 
noteworthy fact that after the removal of the ganglia the esophagus was found 
