The cardiac end of the stomach lies close beneath the diaphragm, and the heart immediately above it. Over-distension of the stomach, due to indigestion or flatulency, may press up the diaphragm and interfere with the proper working of the thoracic organs, causing feelings of oppression in the chest, or palpitation of the heart.

What lies between the right end of the stomach and the diaphragm? What is the size of the stomach?

What may be seen on examining the mucous membrane of the stomach with a hand lens? What does a more powerful magnifying instrument show? What is the function of the gastric glands?

Describe the muscular coat of the stomach. What is its function ? What is the pyloric sphincter? Its function? What happens When the pyloric sphincter relaxes during gastric digestion?

Fig. 49. Diagram of abdominal part of alimentary canal. C, the cardiac, and P, the pyloric end of the stomach; D, the duodenum ; J, i, the convolutions of the small intestine; CC, the cæcum with the vermiform appendix; AC, ascending, TC, transverse, and DC, descending colon; R, the rectum.