12 PROFESSOR D. J. CUNNINGHAM 



used for the introduction of food or it may be amniotic fluid into the stomach, and the 

 occasional conduction of material out of the stomach. It lies in the lowest part 

 of the posterior mediastinum, where this is bounded in front by the back of the 

 diaphragm, and the occurrence of a dilatation in this situation can readily be explained 

 on mechanical grounds, seeing that at this point the gullet receives less perfect support 

 from its immediate surroundings than elsewhere, and from the fact that it is somewhat 

 compressed immediately above and below the place where the expansion takes place. 

 Above the ampulla the gullet is flattened from before backwards by the application of 

 the pericardium and heart (PL I. fig. 10), whilst at the lower end of the dilatation the 

 tube is grasped by the muscular margins of the oesophageal opening in the diaphragm.* 

 An excellent illustration of the ampulla phrenica in relation to its surroundings may 

 be seen in the Edinburgh Stereoscopic Atlas (56). 



The antrum cardiacum t is merely another name for the intra-abdominal part of the 

 oesophagus. As Hasse and Stricker point out, it is funnel-shaped — the broad 

 end of the funnel being the part by which its junction with the stomach is effected 

 (PL I. figs. 6 and 10). This junction takes place at the upper part of the lesser 

 curvature, and it may have the appearance of being to a large extent shifted on to the 

 upper (anterior ?) surface of the stomach in cases where the organ assumes a horizontal 

 position (PL I. figs. 7 and 8). As a rule the antrum cardiacum is separated sharply, on 

 its left side, from the fundus by a groove or sulcus termed by His (22) the incisura 

 cardiaca, whereas on its right side it becomes confluent with the lesser curvature, 

 or it may be the upper surface of the stomach, without any bounding demarcation. 

 The incisura cardiaca is seen in the interior of the stomach in the form of a fold 

 or ridge. When the stomach is full and the notch on the exterior is deep, this 

 fold is very projecting, and Braune (3) and His have attributed to it in this 

 condition a valvular action by means of which the gastric contents are prevented from 

 passing back through the cardiac opening into the gullet. 



Pyloric Part of Stomach. — The demarcation between the cardiac and pyloric 

 portions of the stomach is seen on the lesser curvature in the shape of a notch or 

 angular depression, which is produced by an elbow-like bend (Cruveilhier (9) ) in the 

 organ at this point (PL I. figs. 6, 7, and 8). To this notch in the lesser curvature 

 His has applied the term of incisura angularis. Before the peritoneal folds are 

 removed from the stomach the vessels are seen stretching somewhat tightly across the 

 incisura angularis, and when these are taken away and the organ is freed from its 

 omenta, the furrow loses something of its depth and sharpness, unless the abdominal 

 viscera have been hardened in situ. The position of the- incisura is not always the 

 same ; it is influenced by the filling of the stomach ; it then tends to move towards the 

 pylorus. In the latter stages of the emptying process it may disappear altogether. 



* If an injection mass be forcibly introduced into the stomach, so that there is an escape into the oesophagus, or, on 

 the other hand, if the stomach be forcibly filled through the gullet, an expansion corresponding to the ampulla phrenica 

 very frequently appears on the oesophagus. 



t The term antrum cardiacum was first applied by Luschka to this section of the oesophagus. 



