THE MOUTH CAVITY. 



133 



isthmus of the fauces) at the 

 another, the pharynx or throat 

 chamber, which narrows again 

 at the top of the neck into 

 the gullet or oesophagus, which 

 runs as a comparatively narrow 

 tube through the thorax, and 

 then, passing through the dia- 

 phragm, dilates in the upper rn 

 part of the abdominal cavity 

 to form the stomach (see Fig. 

 1). Beyond the stomach 

 the channel again narrows to 

 form a long and greatly coiled 

 tube, the small intestine, which 

 terminates by opening into the 

 large intestine, which, though 

 shorter is wider, and ends by 

 opening on the exterior. 



The Mouth Cavity. (Fig. 

 41) is bounded in front and 

 on 



cheeks, below by the tongue, 

 k, and above by the palate, 

 which latter consists of an an- 

 terior part, I, supported by 

 bone and called the hard pal- 



back of the mouth, from 



FIG. 41. The mouth, nose and 

 pharynx, with the commencement of 

 the Sides by the lips and the gullet and larynx, as exposed by 



^ -* o Okofi/-kn o littlo tf\ tVitk loff r\f fVii wk_ 



a section, 



left of the me- 



larynx; e, epiglottis; /, soft palate; 

 g, opening of Eustachian tube ; A:, 

 tongue; Z, hard palate; m, the sphe- 

 noid bone on the base of the skull ; n, 

 the fore part of the cranial cavity; 

 o,p, q, the turbinate bones of the out- 

 er side of the left nostril chamber. 



What is the isthmus of the fauces? Where does the gullet begin? 

 Through what regions of the body does it pass? Where does the 

 stomach lie? What part of the alimentary canal succeeds the 

 stomach? Describe it briefly. How does it end? How does the 

 large intestine differ from the small? How does it end? 



What are the boundaries of the mouth cavity? Of what parts 

 does the palate consist? 



