THE STOMACH 



1161 



fossa and by the other to the postero-lateral aspect of the colon. In some 

 instances additional fossae, the retrocecal fossae, are present. 



3. The intersigmoid fossa (recessus intersigmoideus) is constant in the fetus and 

 during infancy, but disappears in a certain percentage of cases as age advances. 

 Upon drawing the sigmoid colon upward, the left surface of the sigmoid mesocolon 

 is exposed, and on it will be seen a funnel-shaped recess of the peritoneum, lying 

 on the external iliac vessels, in the interspace between the Psoas and Iliacus muscles. 

 This is the orifice leading to the intersigmoid fossa, which lies behind the sigmoid 

 mesocolon, and in front of the parietal peritoneum. The fossa varies in size; in 

 some instances it is a mere dimple, whereas in others it will admit the whole of the 

 index finger. 1 



Inferior ileocecal * 



fold 



Inferior ileocecal fossa 



Mesenteriole of 

 vermiform process 



Mesentericoparietal 

 fold 





Cecal fossa 

 FIG. 1045. The cecal fossa. The ileum and cecum are drawn backward and upward. (Souligoux.) 



The Stomach ( Ventriculus ; Gaster). 



The stomach is the most dilated part of the digestive tube, and is situated between 

 the end of the esophagus and the beginning of the small intestine. It lies in the 

 epigastric, umbilical, and left hypochondriac regions of the abdomen, and occupies 

 a recess bounded by the upper abdominal viscera, and completed in front and on 

 the left side by the anterior abdominal wall and the diaphragm. 



The shape and position of the stomach are so greatly modified by changes within 

 itself and in the surrounding viscera that no one form can be described as typical. 

 The chief modifications are determined by (1) the amount of the stomach contents, 

 (2) the stage which the digestive process has reached, (3) the degree of develop- 

 ment of the gastric musculature, and (4) the condition of the adjacent intestines. 

 It is, however, possible by comparing a series of stomachs to determine certain 

 markings more or less common to all (Figs. 1046, 1047, 1048, 1049). 



The stomach presents two openings, two borders or curvatures, and two surfaces. 



Openings. The opening by which the esophagus communicates with the 

 stomach is known as the cardiac orifice, and is situated on the left of the middle 

 line at the level of the tenth thoracic vertebra. The short abdominal portion of the 

 esophagus (antrum cardiacum) is conical in shape and curved sharply to the left, 





1 On the anatomy of these fossae, see the Arris and Gale Lectures by Moynihan, 1899. 



