THE ABDOMEN. 169 



lumbar of either side ; and the kidneys lie in the right 

 and left lumbar, the spleen, the left hypochondriac. 

 The student is frequently called upon to map out or 

 percuss some larger viscus such for example, as the 

 liver the position of which is indicated as follows : It 

 fills the right hypochondriac region and concavity of the 

 diaphragm, and is almost completely concealed by the 

 overhanging of the ribs ; part of the left lobe lies in the 

 epigastric and left hypochondriac regions. It projects 

 upwards into the thorax, and is separated from its wall 

 by the thin lower margin of the right lung and the dia- 

 phragm. In this region its upper margin is about the 

 fifth intercostal space ; referred to a line drawn from the 

 posterior boundary of the axilla vertically to the crest 

 of the ilium, its margin would be about the seventh in- 

 tercostal space. In the mesial line it is not easy to dis- 

 tinguish the upper boundary of the liver from the lower 

 margin of the heart. 



For surgical and operative reference, however, the re- 

 gions of the abdomen will be considered under the heads 

 of (1) Abdominal parietes ; (2) Such portions of the 

 abdominal cavity as are of practical surgical importance ; 



(3) Pelvis. 



(1) Abdominal Parietes. 



The region of the abdominal parietes may be divided 

 as follows (1) Antero-lateral (2) Inguinal ; (3) Crural ; 



(4) Lumbar. 



(1) Antero-lateral Region of the Abdomen Dissection. 

 On removing the skin, which is very lax, excepting at 

 the umbilical depression, is the subcutaneous cellular 

 tissue and fascia, which latter may be divided into as 



