58 UNIVERSITY OF MISSOURI STUDIES 



topography to require a separate discussion of each. 



The right kidney is of a long oval shape with its tviro 

 margins of nearly the same curvature. It lies upon the 

 posterior body wall in the right lumbar region, and ex- 

 tends from the level of the middle of the twelfth thoracic 

 to the middle of the third lumbar vertebra. Its long 

 axis extends from below upward, backward and inward, 

 and if prolonged upwards it would cross the midplane 

 behind the middle of the tenth thoracic vertebra. The 

 upper pole is about 3.5 cm. from the midplane and 3.5 cm. 

 behind the midaxillary plane while the lower pole is about 

 9 cm. from the midline in the midaxillary plane. Thesupero- 

 external half of the posterior surface lies over the eleventh 

 intercostal space, and twelfth rib (Plates XXIX and 

 XXXIII). The lower half of the organ lies below and in- 

 ternal to the twelfth rib. The kidney is separated from 

 the vertebral column above the second lumbar vertebra by 

 the diaphragm, and below this level by the psoas major. 



The anterior surface of the right kidney is peritonaeal 

 for the most part, and in relation with the posterior part of 

 the inferior surface of the liver. When seen from the front 

 the kidney is nearly covered by the eighth, ninth and tenth 

 right costal cartilages (Plates XXVIII and XXXII). The 

 lower half of the suprarenal fits over the upper part of the 

 medial border and separates the kidney from the vena cava 

 inferior (Plate XVI). The duodenum is bound to the 

 medial border and anterior surface from the suprarenal down 

 to the lower part of the hilus. From the hilus to the lower 

 pole, external to the duodenum, the hepatic flexure and as- 

 cending colon cover the internal part of the anterior sur- 

 face of the kidney. The hilus is opposite the second lum- 

 bar vertebra. 



The left kidney is shorter, broader and thicker than 



