THORACIC GAXGLIA. 695 



Fig. 451. DIAGRAMMATIC VIEW OP THE SYMPATHETIC CORD OP THE RIGHT SIDT-, SHOWING 



ITS CONNECTIONS WITH THE PRINCIPAL CEREBRO-SPINAL NERVES AND THE MAIN 



PREAORTIC PLEXUSES. 



Cerebro-spinal Nerves. VI, a portion of the sixth cranial nerve as it passes through 

 the cavernous sinus, receiving two twigs from the carotid plexus of the sympathetic nerve; 

 0, ophthalmic ganglion connected by a twig with the carotid plexus ; M, connection of the 

 spheno-palatine ganglion by the Vidian nerve with the carotid plexns ; C, cervical plexus; 

 Br, brachial plexus ; D 6, sixth intercostal nerve ; D 12, twelfth ; L 3, third lumbar 

 nerve; S 1, first sacral nerve ; S 3, third ; S 5, fifth ; Cr, anterior crural nerve ; Cr', great 

 sciatic ; pn, pneumo-gastric nerve in the lower part of the neck ; r, recurrent nerve 

 winding round the subclaviau artery. 



Sympathetic Cord. c, superior cervical ganglion ; </, second or middle; c", inferior; 

 from each of these ganglia cardiac nerves (all deep on this side) are seen descending to 

 the cardiac plexus; d 1, placed immediately below the first dorsal sympathetic ganglion : 

 d 6, is opposite the sixth; 11, first lumbar ganglion; eg, the terminal or coccygeal 

 ganglion. 



Preaortic and Visceral Plexuses. pp, pharyngeal, and, lower down, laryngeal 

 plexus ; p I, posterior pulmonary plexus spreading from the pneumo-gastric on the back 

 of the right bronchus ; c a, on the aorta, the cardiac plexus, towards which, in addition 

 to the cardiac nerves from the three cervical sympathetic ganglia, other branches are seen 

 descending from the pneumo-gastric and recurrent nerves ; c o, right or posterior, and c o', 

 left or anterior coronary plexus ; o, cesophageal plexus in long meshes on the gullet ; sp, 

 great splanchnic nerve formed by branches from the fifth, sixth, seventh, eighth, and 

 ninth dorsal ganglia; +, small splanchnic from the ninth and tenth ; + +, smallest or 

 third splanchnic from the eleventh : the first and second of these are shown joining the 

 solar plexus, so; the third descending to the renal plexus, re; connecting branches 

 between the solar plexus and the pneumo-gastric nerves are also represented ; p n', above 

 the place where the right pneumo-gastric passes to the lower or posterior surface of the 

 stomach ; p n", the left distributed on the anterior or upper surface of the cardiac portion 

 of the organ : from the solar plexus large branches are seen surrounding the arteries of 

 the cceliac axis, and descending to m s, the superior mesenteric plexus ; opposite to this 

 is an indication of the suprarenal plexus ; below r e (the renal plexus), the spermatic 

 plexus is also indicated ; a o, on the front of the aorta, marks the aortic plexus, formed 

 by nerves descending from the solar and superior mesenteric plexuses and from the lumbar 

 ganglia ; m i, the inferior mesenteric plexus surrounding the corresponding artery ; h y, 

 hypogastric plexus placed between the common iliac vessels, connected above with the 

 aortic plexus, receiving nerves from the lower lumbar ganglia, and dividing below into the 

 right and left pelvic or inferior hypogastric plexuses ; p I, the right pelvic plexus ; from 

 this the nerves descending are joined by those from the plexus on the superiorjiemor- 

 rhoidal vessels, m i', by sympathetic nerves from the sacral ganglia, and by numerous 

 visceral nerves from the third and fourth sacral spinal nerves, and there are thus formed 

 the rectal, vesical, and other plexuses, which ramify upon the viscera from behind for- 

 wards and from below upwards, as towards i r, and v, the rectum and bladder. 



distributed in a great measure to the thoracic aorta, the vertebrae, and liga- 

 ments. Several of these branches enter the posterior pulmonary plexus. 



The branches furnished by the lower six or seven ganglia unite into three 

 cords on each side, which pass down to join plexuses in the abdomen, and 

 are distinguished as the great, the small, and the smallest splanchnic nerve. 



THE GREAT SPLANCHNIC NERVE. 



This nerve is formed by the union of small cords (roots) given off by the 

 thoracic ganglia from the fifth or sixth to the ninth or tenth inclusive. By 

 careful examination of specimens after immersion in acetic or diluted nitric 

 acid, small filaments may be traced from the splanchnic roots upwards as 

 far aa the third ganglion, or even as far as the first (Beck, in the " Philo- 

 sophical Transactions," Part 2, for 1846). 



Gradually augmented by the successive addition of the several roots, the 

 cord descends obliquely inwards over the bodies of the dorsal vertebrae ; 

 and, after perforating the crus of the diaphragm at a variable point, termi- 



