THE ALIMENTARY CANAL AND ITS APPENDAGES. 329 



tine, much shorter although wider than the small, and ter- 

 minating by an opening on 

 the exterior. 



The Mouth - cavity (Fig. 

 105) is bounded in front and 

 on the sides by the lips and 

 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- 

 ate, and a posterior, /, con- 

 taining no bone, and called 

 the 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 arches 

 down over the back of the 

 mouth, hanging like a cur- 

 tain between it and the pharynx, FIG. 105. The mouth, nose and pha- 



i i -IT j.i rynx. with the commencement of the 

 as Can be Seen by holding the gullet and larynx, as i exposed by 



mouth open in front of 

 looking-glass. From the mid- 

 dle 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 the teeth are implanted. 

 During life two sets of teeth are developed; the first or milk 

 set appears soon after birth and is shed during childhood, 

 when the second or permanent set appears. 



The teeth differ in minor points from one another, but 

 in each 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, 



a 



section, a little to the left of the me- 

 & dian plane of the head, a, vertebral 

 column ; 6, gullet : c, windpipe ; d, 

 larynx ; e, epiglottis ; f. soft palate ; 

 g, opening of Eustachian tube ; fc, 

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

 noid bone on the base of the skull ; n, 

 the fore part of the cranial cavity; 

 <>. p, q, the tubinate bones of the out- 

 er side of the left nostril-chamber. 



