THE CfELIAC I'LKXl'X 1015 



nerve, and, near its lower border, lying over the origin of tlie renal artery, is a more 

 or less detached pan , known as the aortico-renal ganglion. This ganglion reee 

 the lesser splanchnic nerve and may seemingly give origin to the greater part of the 

 renal plexus. Another part of the cirliac ganglion, often found behind the origin 

 of the superior inesenieric artery, is known as the superior mesenteric ganglion 

 (fig. 721). 



From the cceliac plexus and its ganglia subordinate plexuses are continued upon 

 the aorta and its brandies. These comprise both paired and unpaired plexuses. 

 The paired plexuses are the phrenic, suprarenal and renal, t he spermatic in the male, 

 and, in the female, the ovarian plexuses. The unpaired plexuses are the aortic, 

 hepatic, splenic, superior gastric, inferior gastric, superior mesenteric, and inferior 

 mesenteric. 



That part of the coeliac plexus surrounding the cceliac artery was formerly de- 

 scribed as the adiac plexus. It is better considered as an unnamed part of the larger 

 cceliac plexus. This part of the plexus receives fibres from both vagus nerves, and 

 gives filaments that form plexuses around the branches of the cceliac artery and their 

 ramifications. 



The paired subordinate plexuses : (1) The phrenic (diaphragmatic) plexuses 

 consist of fibree from the upper part of the cceliac ganglia, which follow the inferior 

 phrenic arteries and their branches on the under surface of the diaphragm (fig. 721). 

 Filaments are given off by the roots of the plexuses to the suprarenal bodies, and 

 others unite with the terminal branches of the phrenic nerves. The point of junc- 

 tion with the right phrenic nerve is marked by the phrenic ganglion, from which 

 branches are distributed to the inferior vena cava, to the right suprarenal body, and 

 to the hepatic plexus. 



(2) The suprarenal plexuses are comparatively large plexuses, formed mainly 

 by branches from the coeliac (semilunar) ganglia. However, fibres come to them 

 from the cceliac plexus along the suprarenal arteries, from the phrenic plexus 

 along the inferior phrenic arteries, and from the renal plexus, along the inferior 

 suprarenal arteries. They are distributed to the substance of the suprarenal bodies. 



(3) The renal plexuses receive fibres from the lower part of the cceliac ganglia 

 and from the creliac and aortic plexuses. They also receive filaments from the 

 least splanchnic nerves, when these nerves are present, and sometimes filaments 

 from the small splanchnic nerves and from the first lumbar ganglion of the sympa- 

 thetic trunk. These plexuses pass along the renal arteries into t he substance of the 

 kidneys. Most of the fibres of each renal plexus are grey fibres, and as they pass to 

 the kidneys small renal gam/liu are developed upon them. Both renal plexuses 

 give branches to the corresponding spermatic plexuses and to the ureter, and the 

 right renal plexus gives filaments also to the inferior vena cava. 



(4 a) The spermatic plexuses (fig. 721) are formed by fibres from the renal and 

 aortic plexuses. They accompany the spermatic arteries and are joined at the ab- 

 dominal inguinal (internal abdominal) ring by fibres that have passed along the vas 

 deferens from the pelvic plexuses. Their terminal filaments are distributed to the 

 testis and the epididymis. 



(4 b) The ovarian plexuses are formed in the female like the spermatic plexuses 

 in the male. They accompany the ovarian arteries and, in the broad ligament, 

 receive fibres from the utero-vaginal plexus. They supply the ovaries, the broad 

 ligaments, and the Fallopian tubes, and send some fibres to the fundus of the uterus, 

 where they become continuous with the utero-vaginal plexus. 



The unpaired subordinate plexuses: (1) The abdominal aortic plexus is 

 formed by two strands of fibres which descend along the sides of the aorta and 

 communicate with each other across its ventral aspect. It is connected above with 

 the renal plexuses, and it receives peripheral branches from some of the lumbar 

 ganglia of the sympathetic trunk on each side. It often contains a number of gan- 

 glia, which are situated at the {joints where the peripheral branches join the plexus, 

 and it terminates below, chiefly by anastomoses with the hypogastric plexus (figs. 

 721 and 722). Besides giving filaments to the inferior vena cava, it also gives 

 fibres that form plexuses along each of the branches of the aorta. The fibres that 

 pass from the lower end of the aortic ple\us upon the common iliac artery form 

 the iliac plexus, which is continued along the femoral artery as the femoral plexus, 

 and still further along the jiopliteal artery as the popliteal plexus. 



(2) The superior gastric (coronary) plexus, receiving filaments from (he 



