

638 



THE KIDNEYS. 



rounder, and nearer the spine, than the lower end, and is 

 also surmounted by the renal capsule. 



The kidneys are seen to vary in number, sometimes there 

 FIG. 205. being only one, 



which is quite 

 large, and ex- 

 tending across 

 the spine. The 

 two kidneys are 

 sometimes con- 

 nected by a 

 transverse band, 

 and Dr. Homer 

 cites an instance 

 where one of the 

 kidneys was in 

 the pelvis in 

 front of the rec- 

 tum. 



The kidneys 

 are essentially 

 glandular or- 



and each consists of membranes,, two distinct sub- 

 stances, the cortical and tubular, the excretory ducts, blood- 

 vessels and nerves. 



Three membranes are given to the kidney, a serous, cel- 

 lulo-adipose, and fibrous. The first comes from the peri- 

 toneum, and is partial, covering only the anterior surface. 

 Of the second, or celMo-adipose, the cellular portion prevails 

 in the young, while the adipose is most abundant in the 

 adult. The third orfbrous is the proper coat of the kidney. 

 It forms a capsule which completely envelops the surfaces, 

 and enters the hilus along with the blood-vessels. This 

 membrane, as already stated, is fibrous, and is also strong, 

 elastic, smooth, and semi-transparent. It adheres to the sur- 



FIG. 205 represents the Urinary Apparatus, a a Kidneys. 6 6 Capsulae 

 renalis. c c Ureters, d Bladder, t Rectum. / Renal arteries, g Aorta. 

 h Its division into the iliacs. t Point where ureters cross the iliacs. 



