134 THE HUMAN BODY. 



ate, and a posterior, /, containing no bone, and called tlie 

 soft palate. The two can readily be distinguished by ap- 

 plying the tip of the tongue to the roof of the mouth and 

 drawing it backwards. The hard palate forms the parti- 

 tion between the mouth and nose. The soft palate archec 

 down at the back of the mouth, hanging like a curtain 

 between it and the pharynx, as can be seen on holding the 

 mouth open in front of a looking-glass. From ihe middle 

 of its free border a conical process, the uvula, hangs down. 



The Teeth. Immediately within the cheeks and lips are 

 two semicircles, formed by the borders of the upper and 

 lower jaw-bones, which are covered by the gums, except at 

 intervals along their edges where they contain sockets 

 in which teeth are implanted. During life two sets of 

 teeth are developed : the first or milk set appear soon after 

 birth and are shed during childhood, when the second or 

 permanent set appear. 



The General Structure of a Tooth. The teeth differ in 

 minor points from one another, but in all, three parts are 

 distinguishable ;* one, seen in the mouth, and called the 

 crown of the tooth; a second, imbedded in the jaw-bone, 

 and called the root or fang; and between the two, embraced 

 by the edge of the gum, a narrowed portion, the neck or 

 cervix. By differences in their forms and uses the 

 teeth are divided into incisors, canines, bicuspids, and 



How can we feel the difference between them ? What cavities 

 does the hard palate separate? Where does the soft palate lie? 

 What is the uvula ? 



What do we find inside the lips? Where are the gums? What 

 do the margins of the jaw bones contain ? What are the milk teeth ? 

 What the permanent ? 



What parts may we distinguish in every tooth? Into what 

 groups are teeth divided? Why? 



* A number of teeth can be readily obtained from a dentist, and will be found 

 of great use in connection with this lesson. 



