LECTURES ON THE SYMPATHETIC NERVOUS 

 SYSTEM.^ 



By G. Carl Huber, M. D. 



Asst. Prof, of Histology and Embryology in the University of Michigan. 



The term sympathetic nervous system is applied to a series 

 of ganglia, united by intervening nerves, found on either side 

 of the vertebral column, and extending from its cephalic to its 

 caudal end. These ganglia with their uniting nerves form the 

 two great gangliated cords or chains, and as such are found 

 among all vertebrate classes, with the possible exception of 

 some of the lowest fishes. For purposes of description, these 

 cords are divided into a cervical, dorsal, lumbar and sacral por- 

 tion, the number of ganglia in each division corresponding in 

 the main with the number of vertebrae found in each of the 

 above named regions ; with this proviso that in the cervical 

 region the number of ganglia is often found reduced to three. 

 The sympathetic system includes further a number of so-called 

 cra?iial ganglia, namely the spheno-palatine, the otic, ciliary, sub- 

 lingual and submaxillary, all of which are paired, and three un- 

 paired ganglia or aggregations of ganglia, found in the median 

 line, in front of the spinal column. Of these, the cardiac is 

 found in the thorax, the semilunar in the abdomen and the hypo- 

 gastric in the pelvis. The sympathetic system comprises, fur- 

 ther, myriads of smaller ganglia, the greater number of which 

 are not to be seen with the naked eye. These are found in the 

 coats of the intestine, the walls of the trachea and bronchi, in 

 the heart and probably in or near all the larger glands of the 

 body. From all these widely distributed ganglia, smaller or 

 larger nerves, composed of a varying number of so-called sym- 

 pathetic nerve fibers, have their origin. 



Characteristic of this system is, that these nerves are 



' Being four special lectures delivered to the Medical Students of the Uni- 

 versity of Michigan in May, 1897. 



