44 Analyses of a Series of Papers, by Mr. C. Bell, 



in no measure deprived of it when a nerve not of this class is 

 divided- 



The nerves of the irregular and complex system, in contra- 

 distinction to those of the original and symmetrical one, do 

 not arise by double roots, nor have they any ganglia on their 

 origins ; they come off from the medulla oblongata and the 

 upper part of the spinal marrow; and from this origin they 

 diverge to those several remote parts of the frame which are 

 combined in the motion of respiration. These are the nerves 

 which give the appearance of confusion to the dissection, be- 

 cause they cross the others, and go to parts already plentifully 

 supplied from the other system. 



The author enumerates the following as respiratory nerves, 

 according to their functions : 



1. The par vagum, or the eighth pair of Willis, takes its 

 course to the larynx, lungs, heart, and stomach, and associates 

 them together; they being at the same time supplied with 

 nerves from other sources. 



2. The portio dura of the seventh or respiratory nerve of 

 the face. By the division of this nerve the face is deprived 

 of its consent with the lungs, and of all expression of emotion. 



3. The spinal accessory, or superior respiratory nerve of the 

 trunk. In its course it supplies the muscles of the neck and 

 shoulder, which are already profusely supplied by the regular 

 system of nerves. When it is divided, those muscles which 

 were in action as respiratory muscles cease their co-operation, 

 but remain capable of voluntary actions. 



4. The phrenic, or diaphragmatic, or great internal respira- 

 tory nerve. This is the only one of the system which has 

 been known as a respiratory nerve. 



5. The external respiratory nerve, connected with and re- 

 sembling the former as to origin; it passes through the axilla 

 and goes to the muscles on the outside of the ribs, which are 

 supplied with nerves from the other system coming out be- 

 twixt the ribs as well. This nerve has been entirely over- 

 looked. 



These four last-mentioned nerves govern the muscles of the 

 face, neck, shoulders, and chest, in the actions of excited re- 

 spiration, and are absolutely necessary to speech and expres- 

 sion. Under the same class, moreover, must be ranked the 

 nerves which go to the tongue, throat, and windpipe, these be- 

 ing no less essential to complete the act of respiration ; as the 

 glossopharyngeal, the lingual, or ninth of Willis, and the 

 branches of the par vagum to the superior and inferior larynx. 



With the view to give a more detailed illustration of the 

 nerves being divisible or distinguishable into two distinct clasfces, 



Mr. 



