1156 



THE DIGESTIVE SYSTEM. 



separated- by an intervening depression. Into the right cupola fits the greater pan 

 of the liver ; in the left lie a part of the stomach and spleen. On the superio] 

 surface of each cupola is placed the base of the corresponding lung, whilst betweei 

 them, on the depression, rests the inferior surface of the heart. 



During expiration, the right cupola ascends almost to the level of the righ 

 nipple ; it is highest at a point about one inch medial to the nipple line, and hen 

 it reaches the superior border of the fifth rib, or even the middle of the fourth inter 

 costal space. On the left side it is one-half to one inch (12-25 mm.) lower, am 

 in the median plane it crosses the inferior extremity of the body of the sternun 

 about the level of the seventh rib cartilage (Fig. 912). 



6th costal cartilage. 



7th costal cartilage 

 Lig. teres 



8th costal cartilage 



Gall-bladder 



9th costal cartilage 



Liver 



10th costal cartilage 

 Duodenum 



Right flexure of colon 

 Kidney 



Caecum - - 



Ileum - 



Vermiform process-- 



Xiphoid process 

 -6th costal cartilage 



7th costal cartilage 



Stomach 



8th costal cartilage 



Transverse colon 

 9th costal cartilage 



10th costal cartilage 

 Duodeno-jerj unal 

 flexure 



Kidney 



Descending colon 

 Mesentery, cut 



Bifurcation of abdomin; 

 aorta 



Iliac colon 

 Pelvic colon 



-Urinary bladder 



FIG. 912. THE ABDOMEN AFTER REMOVAL OF JEJUNUM AND ILEUM. 



Below, the cavity is continued into the cavity of the pelvis minor. 



The anterior wall is formed by the aponeuroses of the three flat abdominal muscle 

 obliquus externus, obliquus interims, and transversus abdominis, together with thi 

 two recti, which latter constitute powerful braces for the wall, on each side of th 

 median plane. 



Anteriorly, below the junction of abdomen and pelvis, lies the pubic symphysi 

 The body of the pubis looks upwards as well as posteriorly, and appears to form 

 support or floor for the viscera contained within the anterior part of the abdomim. 

 cavity. 



The side walls are formed by the muscular portions of the obliqui and tram 

 versi muscles, and below by the iliac bones and the iliacus muscles. 



Finally, the cavity is limited posteriorly by the lumbar portion of the vertebr.- 

 column, with the crus of the diaphragm and psoas major muscle on each side, and tl 

 quadratus lumborum still more laterally. The iliac bones also enter into the form? 

 tion of the inferior portion of the posterior wall. 



The superior portion of the cavity lies under cover of the ribs, which affoi 

 considerable protection to that part of the abdomen, particularly at the sides ar 



