140 



TOPOGRAPHICAL ANATOMY OF THE 



stituents of the spermatic cord from the abdominal ring of the inguinal 

 canal should be noted. The ductus deferens, enclosed in a fold of 

 peritoneum of increasing width, at once turns into the pelvis, where it 

 will be found crossing the dorsal surface of the urinary bladder obliquely 

 as it approaches the median plane of the body. The internal spermatic 

 vessels, enclosed in a small and variable peritoneal fold, proceed 

 towards the vertebral column. 



The kidneys (Renes). — The kidneys are placed against the dorsal 

 wall of the abdomen and are embedded in loose areolar tissue generally 

 containing a considerable quantity of fat. In cleaning away the fat, 

 care must be taken not to injure the ureters and the adrenal glands. 



TJ\'er. 



Vena cava caudalis. 

 Aorta. 



A. renalis 

 Diaphragm. 



Spleen 



Diaphragm. 

 \ M. psoas major. 



M. psoas minor. 



M. psoas major. 



M. psoas minor. 



Fig. 64. — Outline of the dorsal surface of the kidneys, to show the relative 

 position, shape and relations of the two organs. 



The two kidneys differ in position, size, form and relations. The 

 right kidney is more cranial than the left, and, in terms of the skeleton, 

 extends from the level of the transverse process of the first lumbar 

 vertebra to the interspace between the sixteenth and fifteenth ribs. 

 The cranial end of the left kidney lies under the eighteenth rib (or 

 sometimes the seventeenth interspace), while its caudal end reaches the 

 level of the transverse process of the third lumbar vertebra. 



The right kidney (about 700 grammes in weight) is generally larger 

 than the left (about 680 grammes). 



The difference in the shape of the two organs is sometimes very 

 striking. The right kidney is broader than it is long, and has an 

 outline that may be likened to that of the heart on a playing-card. 

 The left kidney, on the other hand, is shaped like an elongated bean, 

 and is longer than it is broad. Though this may be regarded as the 



