THE KIDNEYS. 191 



the solar plexus, accompanies the hepatic artery in its sub- 

 divisions. The liver also receives branches from the phre- 

 nic and pneumogastric nerves. 



, 



DISSECTION IV. 



THE SUPRA-RENAL CAPSULES. 



The supra-renal capsules are to be sought for beneath the perito- 

 um, high up in the lumbar region, on each side of the spinal 

 column. 



The SUPRA-RENAL CAPSULES are small, flat, crescentic 

 bodies, covered in by peritoneum and surmounting the kid- 

 neys, to which their concave surface is sometimes directly 

 applied ; an interval not unfrequently, however, exists 

 between the two organs. They are of a yellowish color, 

 and easily obscured among the fat and cellular tissue of 

 the surrounding parts. The right capsule rests upon the 

 diaphragm between the kidney and the liver, oftentimes 

 as closely adherent to one as the other of these organs. 

 The left capsule also rests upon the diaphragm, beneath 

 the pancreas and spleen. For so small organs they are 

 largely supplied both with nerves and arteries, the former 

 constituting a supra-renal plexus derived from the solar 

 plexus, the latter being branches of the aorta, and the 

 phrenic and renal arteries ; the supra-renal vein terminates 

 sometimes in the inferior cava and sometimes in the renal 

 vein. Upon section, they are seen to be made up of an 

 external or cortical substance, of a yellow color, and an 

 internal or medullary substance, dark and semi-fluid ; an 

 internal cavity is sometimes described, but it is a question 

 if it be not the result of post-mortem degeneration. One 

 or two instances of entire absence of the supra-renal 

 capsules have been reported, and in the foetus they have 

 been found fused into one body across the vertebral column. 



THE KIDNEYS. 



The kidneys occupy the lumbar region on each side of the verte- 

 bral column, lying beneath the peritoneum, enveloped in fat and 

 cellular tissue. To expose them, both the peritoneum and lumbar 

 fascia must be removed, and the ureter should be traced downward, 

 either in part or the whole of its course. 



