ABDOMINAL CAVITY 



489 



left with the ileum and the vermiform process. It is com- 

 pletely surrounded by peritoneum and is supplied with blood 

 by branches derived from the loop between the termination 

 of the superior mesenteric artery and its ileo-colic branch. 



The Vermiform Process springs from the medial and 

 posterior aspect of the caecum, about an inch below the ileo- 

 caecal junction, and passes either upwards and to the left, 

 towards the left hypochondrium, downwards into the pelvis 

 across the right external iliac artery, or upwards behind the 

 caecum and the ascending colon. It invariably occupies the 



Frenulum of valve 



Taenise col 



Anterior taenia coli 



Upper segment 

 of valve 



Frenulum of valve 



Orifice of ileum 



Inferior segment 

 of valve 



Ileum 



Orifice of vermiform process 



FIG. 1 88. Caecum which has been distended with air and dried, and then 

 opened to show Ileo-Caacal Opening and Valve. (Birmingham.) 



last position if a retro-colic pouch is present. It is attached 

 by a mesentery, the meso-appendix, to the posterior surface 

 of the lower part of the mesentery of the ileum. 



Dissection. Turn the caecum upwards, remove the peritoneum from 

 the wall of the iliac fossa behind it and clear away the extra-peritoneal fat. 

 Note that the peritoneum and fat separate the caecum from the right 

 psoas and iliacus muscles, and from the femoral nerve (O.T. anterior crural) 

 in the angle between them. The anterior surface of the caecum is in rela- 

 tion with the anterior wall of the abdomen or is separated from it by the 

 lower part of the great omentum. 



Cut away a portion of the right lateral wall of the caecum and examine 

 the ileo-csecal orifice and the orifice of the vermiform process from the 

 interior of the intestine. 



