376 ANATOMY FOR NURSES [Chap. XIX 



The vertebral ganglia. — The vertebral ganglia consist of a 

 chain of ganglia situated on each side of the spinal column, and 

 extending from the base of the skull to the cocc^'x. There are 

 about forty-nine of these ganglia, twenty-four on each side of the 

 spine, and one in front of the coccyx. They are connected with 

 each other by nerve-fibres called ganglia cords, and with the spinal 

 nerves by branches which are called rami communicantes} They 

 are also connected to the viscera and blood-vessels by branches 

 which travel different pathways: (1) they pass directly to the 

 viscera ; (2) they converge to form three main nerve-trunks, 

 called the great splanchnic, the small splanchnic, and the least 

 splanchnic, and then send branches from these trunks to the vis- 

 cera ; (3) they join the collateral ganglia and plexuses ; (4) they 

 join the spinal nerves, and in them reach the part of the body for 

 which they were destined. 



The collateral ganglia. — The collateral or outlying ganglia 

 consist of masses of gray matter and their nerves, which are located 

 principally in the thoracic and abdominal cavities. They are 

 connected with the spinal nerves, with the vertebral ganglia, and 

 send branches to the viscera. These branches form plexuses, the 

 most important of which are : (1) the cardiac plexus, located above 

 the heart and supplying it with sympathetic fibres, (2) the solar 

 plexus, located behind the stomach and supplying most of the ab- 

 dominal viscera, (3) the hypogastric or pelvic plexus, located in the 

 lower part of the abdomen and supplying the viscera of the pelvis. 



The terminal ganglia. — The terminal ganglia include all the 

 ganglia situated in the walls of the organs themselves, as for in- 

 stance those in the walls of the heart, and in the walls of the ali- 

 mentary canal. These ganglia are directly connected with the 

 collateral ganglia, and in some instances the nerves derived from 

 the collateral plexuses form a secondary or terminal plexus on the 

 organs. 



Sympathetic ganglia in the brain and spinal cord. — In connec- 

 tion with a few of the cranial nerves, such as the third and fifth, 

 certain ganglia are found. Sympathetic ganglia are also found 

 in the spinal canal and in the medulla. (See vasomotor centres.) ^ 

 Autonomic system is a name that has recently been suggested for 

 the sympathetic system as outlined above. Prior to the introduc- 



» See page 377. « See page 378. 



