VISCERA 25 



the cavity of the mouth, separating the oral and 

 the pharyngeal cavities. 



3. The Tonsils lie one on either side of the 

 opening leading from the mouth to the pharynx. 

 They are small oval bodies and are partially em- 

 bedded by lateral prolongations of the soft palate. 



4. The Tongue is a muscular organ attached 

 posteriorly to the hyoid bone and for the greater 

 part of its length to the floor of the mouth. It is 

 covered with a mucous membrane, which is smooth 

 below but above is provided with three kinds 

 of papillae. The circumvallate papilla are the 

 rounded prominences situated in two lines con- 

 verging posteriorly at the back part of the tongue. 

 Thzfungiform papillce are smaller and more nu- 

 merous, and are situated on the side and anterior 

 portion of the tongue. ^\\e filiform papilla, the 

 most numerous of all, cover the whole of the 

 upper surface of the tongue. They have large, 

 posteriorly-directed, horny points. 



5. The Pharynx is the large, conical cavity im- 

 mediately behind and below the soft palate. It is 

 the posterior continuation of the mouth cavity. 



6. The Posterior Nares are two openings into the 

 pharynx, situated just above the palate. They 

 pass forward into the nasal cavity. 



7. The Eustachian Tubes are two openings just 

 external to the posterior nares. Their canal places 

 the middle ear in communication with the phar- 

 ynx. 



