71 



which it had lost, and the fibres which were disorganized, the 

 sound vagus on the opposite side being taken as a standard of com- 

 parison. On the sound side, galvanism of the vagus caused each time 

 strong dilatation of the glottis by the retraction of the corresponding 

 arytenoid cartilage. On the operated side, galvanism produced a 

 slight movement of the glottis on the same side by drawing inwards 

 of the arytenoid. 



On the heart, the action of galvanism of the sound vagus was 

 manifest by the stoppage of the pulsation of the carotid arteries 

 and the diminution of their calibre. On the operated side, no in- 

 fluence on the pulsation of the vessels was observed by galvanizing 

 the vagus. When the heart was exposed by removing a portion of 

 the thorax, and keeping up artificial respiration, galvanism on the 

 sound vagus produced complete stoppage of the heart's action, while 

 on the opposite side, irritation of the vagus exerted no influence on 

 the heart. 



The stomach being exposed was found distended with food. Gal- 

 vanism of the sound vagus caused evident contractions of this organ, 

 which were strongest at the neck or constriction which it usually 

 presents (in the rabbit), from whence they radiated in both direc- 

 tions, becoming more and more faint. On stimulating the other 

 vagus, from which the accessory had been virtually eliminated, no 

 perceptible influence was observed. 



Microscopic examination showed that the cervical part of the 

 vagus of the side operated on contained numerous disorganized 

 fibres, almost all collected together in a single fasciculus, which in- 

 cluded only a few normal fibres. In the recurrent branch were dis- 

 organized fibres, corresponding very closely to those found in the 

 vagus above it. Below the recurrent, the vagus and its cardiac, pul- 

 monary and gastric branches consisted almost entirely of normal 

 fibres, most of which, as is well known, are nucleated fibres. 



From the foregoing observations, the author draws the conclusion, 

 that from the spinal accessory are derived the greater part of the 

 motor fibres contained in the vagus, which govern the movement of 

 the larynx, the heart, and the stomach. He likewise infers from 

 the microscopic examination of the vagus below the recurrent, that 

 the motor fibres distributed to the heart and stomach belong almost 

 exclusively to the nucleated or ' Remak ' fibres. 



