640 THE SYMPATHETIC NEEYES AND GANGLIA. 



•with those branches. The plexus and ganglion are smaller on the left than on 

 on the right side. 



Renal Plexus. — The nerves forming the renal plexus, fifteen or twenty in 

 number, emanate for the most part from the outer part of the semilunar gan- 

 glion ; but some are added from the solar and aortic plexuses. More- 

 over, filaments from the smallest splanchnic nerve, and occasionally from the 

 other splanchnic nerves, terminate in the renal plexus. In their course along 

 the renal artery, ganglia of different sizes are formed on these nerves. Lastly, 

 dividing -with the branching of the vessel, the nerves follow the renal arteries 

 into the substance of the kidney. On the right side some filaments are fui-- 

 nished to the vena cava, behind which the plexus passes with the renal artery ; 

 and others go to form the spermatic plexus. 



Spermatic Plexus. — This small plexus commences in the renal, but receives 

 in its course along the spennatic artery an accession from the aortic plexus. 

 Continuing downwards to the testis, the spennatic nerves are connected vdth 

 others which accompany the vas deferens and its artery from the pelvis. 



In the female, the plexus, like the artery, is distributed to the ovary and the 

 uterus. 



Coeliac Plexus. — This plexus is of large size, and is derived from the fore part 

 of the great epigastric plexus. It suiiounds the cceliac axis in a kind of mem- 

 branous sheath, and subdi^-ides, with the artery, into coronary, hepatic, and 

 splenic plexuses, the branches of which form communications corresponding' 

 with the arches of the arterial anastomosis. The plexus receives offsets from one 

 or more of the splanchnic nerves, and on the left side a branch from the pneumo- 

 gastric nerve is continued into it. (Swan.) 



The corona nj 2)h:eus is placed with its artery along the small curvature of the 

 stomach, and imites with the nerves which accompany the pyloric artery, as 

 well as with branches of the pneumo-gastric nerves. The nerves of this plexus 

 enter the coats of the stomach, after running a short distance beneath the 

 peritoneum. 



The h'jm-tic jJ^criis, the largest of the three [divisions of the coeliac plexus, 

 ascends with the hepatic vessels and the bile-duct, and, entering the substance 

 of the liver, ramifies on the branches of the vena porta3 and the hepatic arteiy. 

 Offsets from the left pneumo-gastric and diaphragmatic nerves join the hepatic 

 plexus at the left side of the vessels. From this plexus filaments are furnished 

 to the right suprarenal plexus, as weU as other secondary i^lexuses which 

 follow the branches of the hepatic artery. Thus there is a ci/.sfie plexus to the 

 gall-bladder ; and there are jyijloric. ffa.it ro-rpijjloic, and ffastro-dnodenal plexuses, 

 which unite with coronary, splenic, and mesenteric nerves. 



The sjflcnic jjIiwils. continued on the splenic artery and its branches into the 

 substance of the spleen, is reinforced at its beginning bj' branches from the left 

 semilunar ganglion, and by a filament from the right vagiis nerve. It furnishes 

 the lift fftj,sfro-cj)ij)Ioic and jmncrcatU' plexuses, which course along the corre- 

 sponding branches of the splenic artery, and, like the vessels, are distributed to 

 the stomach and pancreas. 



Superior Mesenteric Plexus. — The plexus accompanying the superior me- 

 senteric artery, whiter in colour and fii-mer than either of the preceding offsets 

 of the solar jilexus enveloiDes the artery in a membranifonn sheath, and receives 

 a prolongation from the junction of the right pneumo-gastric nerve with the 

 cceliac plexus. Near the root of the artery, ganglionic masses (gangl. meseraica) 

 occur in connection -n-ith the nerves of this plexus. 



The oft'sets of the plexus are in name and distribution the same as the vessels. 

 In their progress to the intestine some of the nerves quit the arteries which first 

 supported them, and are directed forwards in the intervals between the vessels. 

 As they proceed they divide, and unite with lateral branches, like the arteries, but 

 without the same regularity : they finally pass upon the intestine along the line 

 of attachment of i!he mesentery. 



The Aortic Plexus. — The aortic or intcmiesenteric plexus, placed along the 

 abdominal aorta, and occupying the interval between the origin of the superior 

 and inferior mesenteric arteries, consists, for the most, of two lateral portions, 



