144 Anatomy Applied to Medicine and Surgery. 



down the chain of thoracic ganglion and through the rami 

 communicantes into the intercostals. With reference to 

 the pain felt over the second left cartilage, the path may 

 he that referred to above, when dealing with pain in the 

 neck in angina pectoris, the particular superficial nerve in 

 the case of pain over the cartilage being the supraclavicu- 

 lar. By means of the cardiac plexuses, and, through their 

 contributing branches from the pneumogastric and the 

 sympathetic nerves, the heart is brought into intimate rela- 

 tionship with other important viscera. Thus, by them, 

 the abdominal viscera are brought into association with 

 the heart, so that any disturbance of these organs shows 

 itself in disorder of the cardiac rhythm, such, for instance, 

 as acceleration of the heart beat, through the cardiac branch 

 of the sympathetic, or, inhibition of it, through the inhibi- 

 tory branch from the pneumogastric. A clinical example 

 of the above effects is seen in injuries to the intestine, 

 where the irritation is conveyed to the solar plexus by the 

 mesenteric nerves and from the solar plexus to the pneu- 

 mogastric, and then through the inhibitory branch of the 

 latter to the heart, causing slowing, and even arrest, of the 

 action of that organ. 



