224 



DIGESTIVE SYSTEM. 



below, and in front, with the larynx continuation of the 

 air passage). A most important feature in deglutition is the 



Fig. 62. Mouth and pharynx.* 



mechanism by which the upper and the lower orifices of com- 

 munication become obliterated. 



When mastication and insalivation are 'completed, the 

 food collects in a single mass on the surface of the tongue, 

 the tip of which touches the roof of the mouth while the 



* fc, h, Buccal aperture. I, Tongue, rf, Lower jaw, with the genio-glossal 

 inserted, e, Hyoid bone. ?/, Epiglottis. . /, Cavity of the larynx (with the 

 opening of the ventricles), c, Velum palati. , Anterior pillar of the uvula. 

 v, Posterior pillar. L Tonsil, s, Narrow part of the pharynx, connected with 

 the oesophagus, z, Orifice of the Eustachian tube, at the upper part of the 

 pharvnx. 



