116 Anatomy of the Rabbit. 



III. THE STOMACH AND SPLEEN. 



The cavity disclosed by the division of the abdominal wall is the 

 peritoneal cavity (cavum peritonaei), the largest of the four great serous 

 sacs representing the primary body-cavity, or coelom (p. 49). The 

 major portion of the cavity is abdominal, but it extends into the pelvis, 

 and, in the male, also into the scrotal sacs. Its lining membrane is that 

 appearing on the body-wall as the parietal peritoneum, noted above, 

 and on the visceral structures as the visceral peritoneum (peritonaeum 

 viscerale). The visceral structures here include the major portions of 

 the digestive and urinogenital systems. 



The general relations of the visceral peritonaeum should first be 

 examined by raising a portion of the small intestine from the left side of 

 the visceral mass. Note its enclosure by a complete serous coat, similar 

 in appearance to the membrane covering the body wall, and the ex- 

 tension of the latter into a mesentery for the support of the structure 

 from the dorsal body-wall. Note the parallel arrangement of the 

 arteries and veins, and also their frequent anastomoses. Lymphatic 

 vessels (lacteal vessels) accompany the bloodvessels in the mesentery, 

 but being transparent are not readily recognizable. Lymph nodes also 

 occur, but in this portion of the mesentery they are aggregated at its 

 dorsal attachment, or root (radix mesenterii). 



1. Displace the posteroventral portion of the liver forward, exposing 

 in this way the ventral surface of the stomach. Without injuring the 

 enclosing peritoneum, examine the contour of the organ and its divisions, 

 as follows : 



(a) The greater curvature (curvatura ventriculi major), its convex 

 posterior surface. 



(b) The lesser curvature (curvatura ventriculi minor), the 

 contracted, concave anterior surface. 



(c) The main portion, or body of the stomach (corpus ventriculi) . 

 It lies for the most part to the left of the median plane. 



(d) The cardia, or area of junction with the oesophagus. 



(e) The fundus, a small sac-like portion lying to the left of the 

 cardia. 



(f) The pyloric limb (pars pylorica), lying to the right of the 

 body of the organ. 



(g) The pylorus, the point of communication of the stomach with 

 the intestine (duodenum). It is marked by an annular 

 constriction, preceding which is a greatly thickened muscular 

 portion of the pyloric limb, known as the pyloric antrum 

 (antrum pyloricum). 



2. Raise the posterior portion of the stomach and turn it forward. 

 Note on the dorsal surface of the greater curvature a dark red, elongated 



