48 



THE DIGESTIVE TEACT. 



tract. 



Fig. 3. 



respiratory passage by the valve-like shutting of the epiglottis. Through 

 the oesophagus the morsel advances "by the contraction of the muscular 

 coat, with a wave-like or undulating motion onward. The food is now de- 

 livered at the cardiac orifice of the stomach, and, entering that organ, is sub- 

 mitted to the gastric juice, which is exuding from the mucous membrane. 

 The digestive tract may be considered as presenting six prominent re- 

 iiiustration of ^ ons ^e mou t n > tne pharynx, the oesophagus, the stomach, 

 the digestive the small intestine, the large intestine. Their relative posi- 

 tion and subdivisions are illustrated in Figure 3. 1, the 

 tongue ; 2, 2, the pharynx ; 3, 3, the 

 oesophagus; 4, the velum pendulum 

 palati ; 5, section of the larynx ; 6, the 

 palate ; 7, the epiglottis ; 8, the thy- 

 roid cartilage; 9, the medulla spina- 

 lis; 10, 10, bodies of vertebra3; 11, 

 12, spinous processes of ditto ; 13, 

 cardiac orifice of stomach ; 14, splenic 

 extremity; 15, pyloric extremity; 16, 

 16, greater curvature; 17, the less 

 curvature ; 18, pylorus ; 19, superior 

 transverse portion of duodenum ; 20, 

 middle or perpendicular portion ; 21, 

 inferior transverse portion ; 22, gall- 

 bladder ; 23, cystic duct ; 24, hepatic 

 duct; 25, ductus communis choledo- 

 chus; 26, its aperture in the duode- 

 num ; 27, duct of the pancreas, empty- 

 ing into the duodenum near to the place 

 of entry of the ductus communis chole- 

 dochus ; 28, commencement of jeju- . 

 num ; 29, 29, 29, jejunum ; 30, 30, 30, 

 ileum; 31, ileum opening into great 

 intestine ; 32, ileo-colic valve ; 33, il- 

 eo-ccecal valve; 34, ccecum; 35, ap- 

 pendix vermiformis ; 36, 36, the as- 

 cending colon ; 37, transverse arch of 

 colon ; 38, descending colon ; 39, sig- 

 moid flexure ; 40, rectum ; 41, anus. 



From the interior or mucous coat of 

 the stomach the gastric juice exudes. 

 This fluid may be best obtained for ex- 

 amination by gastric fistulas artificially 

 The h Uman digestive tract. established in animals. As respects the 



