THE INVOLUNTARY NERVOUS SYSTEM 



Situation of Blood 

 Vessels. 



Situation of Motor Ganglion 

 Cells. 



Roots Containing Connector 

 Nerves. 



Head and Neck. 



Heart. 



Anterior extremity. 



Posterior extremity. 



Kidney. 



Spleen. 



Abdominal viscera. 



Pelvic viscera. 



Superior cervical ganglion. 



Ganglion stellatum and in- 

 ferior cervical ganglion. 

 Ganglion stellatum. 



6th lumbar, yth lumbar, and 



ist sacral ganglion. 

 Renal ganglion. 



Semilunar ganglion. 



Superior mesenteric gang- 

 lion and semilunar gang. 



Inferior mesenteric gang- 

 lion. 



i, 2, 3, 4, 5, thoracic; 2, 3, 4, 

 give maximum effect. 



i, 2, 3, 4, 5, thoracic ; 2, 3, give 

 maximum. 



4) 5, 6, 7, 8, 9, thoracic and 10 

 slightly. 



ii, 12, 13, thoracic; i, 2, lumbar 

 and 3, lumbar slightly. 



4. 5, 6, 7, 8, 9, 10, n, 12, 13, 

 thoracic; i, 2, 3, 4, lumbar. 



3, 4, 5, 6, 7, 8, 9, 10, n, 12, 13, 

 thoracic; i, 2, 3, lumbar. 



6, 7, 8, 9, 10, ii, 12, 13, thor- 

 acic; i, 2, lumbar. 



i, 2, 3, 4, lumbar. 



An examination of this table brings out the striking fact that 

 the innervation of the blood vessels of the upper and lower ex- 

 tremities is practically continuous from one end of the thoracico- 

 lumbar outflow to the other. Also the motor neurons for the 

 blood vessels are situated both in the lateral and collateral chain 

 of ganglia, the former being entirely devoted to the supply of 

 motor nerves to the blood vessels belonging to the structures 

 innervated by the segmental nerves, both spinal and cranial, in- 

 cluding the central nervous system itself, as well as to the 

 thoracic viscera, while the latter supply with motor nerves all 

 the blood vessels of the abdominal and pelvic viscera. 



In certain regions the motor nerves of the blood vessels have 

 not been conclusively determined ; e.g. the vessels of the brain, 

 of the lungs and the coronary vessels of the heart. In all 

 these cases the presence of vaso-constrictor nerves has been 

 denied, or at all events clear evidence of their existence is 

 wanting. Undoubtedly these vessels have muscular walls and 

 equally undoubtedly nerve fibres can be seen in them. I for 

 one cannot believe that muscles exist without motor nerves. 

 The whole discussion is so bound up with the action of adrenalin 

 that it is better not to discuss it here, but to leave it until I come 

 to the action of adrenalin in its bearing upon the nature of the 

 involuntary nervous system. 



2. The motor nerves to the sweat glands. Abundant evidence 

 has been given that the secretion of sweat can be brought about 

 by the stimulation of nerves, and it has been shown conclusively, 



