LECTURE II. 4,7 



lost, whenever we find those intumescences 

 on nerves which are called ganglia, for in 

 these there seems to be a mixture or con- 

 solidation of the nervous matter. It is 

 also lost wherever various nerves unite 

 together, and form a plexus ; in which 

 case the nervous fibrils either coalesce, or 

 become inextricably interwoven with one 

 another. 



The nerve from which the thoracic and 

 abdominal viscera are chiefly supplied, is 

 beset with numerous ganglia and plexuses ; 

 and as we cannot by our will influence the 

 actions of those viscera, and as the iris, the 

 motions of which are also involuntary, is 

 supplied with nerves from a ganglion, it has 

 been thought that ganglia, by intercepting 

 the direct communications between the 

 brain and the extreme branches of nerves, 

 might render parts thus supplied less 

 amenable to the will, and less under the 

 influence of the general affections of the 

 nervous system. It is also thought that 

 ganglia might serve the office of subsidiary 



