CHAPTER XVI 



THE ANATOMY AND PHYSIOLOGY OF THE 

 URINARY APPARATUS (ORGANS); THE 

 SKIN AND ITS APPENDAGES 



THE URINARY ORGANS 



. THE urinary organs include the kidneys, which 

 secrete or excrete the urine ; the ureters convey it to the 

 bladder, where it is retained until voided (micturition) ; 

 then the urethra which discharges it from the body. 



The Kidneys (Renes). The kidneys are situated in 

 the abdominal cavity on each side of the vertebral 

 column, resting on the psoas magnus and the quad-- 

 ratus lumborum muscles'. They are behind the peri- 

 toneum and correspond to the space included between 

 the upper level of the twelfth thoracic above, and 

 opposite the third lumbar vertebra below. The right 

 kidney is lower than the left. In the female they are 

 a little lower than in the male. 



Each is bean-shaped, measures about 4 to 4f inches 

 in length, 2| in breadth, and 1 to If inches in thick- 

 ness, and weighs about 4 to 6 ounces. They lie in the 

 right and left hypochondriurn, the epigastrium, and 

 the right and left lumbar regions. 



Fixation of the Kidney. The kidney is embedded in 

 a mass of fatty tissue (capsule adiposa) surrounded by 

 a fibrous sheath named the fascia renalis continuous 

 with the subperitoneal fascia. 



The Structure of the Kidney. The kidney is made 

 up of a series of tubules supported by a frame-work 

 of connective tissue, and surrounded by small capil- 



