16 REGIONS OF THE ABDOMEN. 



3d. The Urinary Organs, — the Kidneys, the Ureters, and 

 the Bladder. To which should be added the Glandulae Renales. 



4th. The Organs of Generation in part : those of the 

 female sex being almost wholly included in the pelvis ; and 

 those of the male being situated partly within and partly with- 

 out it. 



5th. The Peritoneum and its various processes. The Mes- 

 entery, Omentum, &c. 



6th. A portion of the Aorta, and almost the whole of the 

 Inferior Vena Cava, and their great ramifications ; with such 

 of their branches as are appropriated to the Viscera of the 

 Abdomen and Pelvis. 



7th. Those "portions of the Par Vagum and Intercostal 

 Nerves which are appropriated to the cavity ; and portions of 

 some of the nerves destined to the lower extremities. 



8th. The lower part of the Thoracic Duct, or the Great 

 Trunk of the Absorbent System, with the large branches that 

 compose it, and the glands connected with them : and also 

 those absorbent vessels called Lacteals,znd their glands. 



As the cavity of the abdomen has no natural divisions, 

 anatomists have divided it by imaginary lines into various 

 regions, with a view to precision in their accounts of the situ- 

 ation of the different contained parts. Thus, 



They have, very generally, agreed to apply two transverse 

 lines to form three great divisions ; viz. the Upper, Middle, 

 and Lower : and they have also agreed that each of these divi- 

 sions shall be subdivided into three regions. 



The three regions of the uppermost division are defined 

 with some precision. Those on each side, which are called the 

 Right and Left Hypochondriac regions, occupy the space 

 immediately within the lower ribs and their cartilages ; while 

 the middle space, included within the margins of these carti- 

 lages and a line drawn from the lower edge of the thorax on 

 one side to that on the other, is denominated the Epigastric 

 region. 



The boundaries of the regions below are less precisely 

 defined. 



