BUCCAL CAVITY 299 



b. The upper teeth, comprising the incisors at the 



front of the palate, and the grinders at the sides 

 opposite the junction of hard and soft palates, 

 have already been described (p. 283). 



c. The naso-palatine canals, which connect the nose 



with the buccal cavity, open in a pair of grooves 

 running backwards from the small posterior in- 

 cisors, and about an eighth of an inch behind 

 these. 



d. The tonsils are a pair of small pits at the sides of 



the posterior part of the soft palate, near its 

 hinder border. The outer wall of each is much 

 thickened, forming a papiUa which nearly closes 

 the opening. 



2. The floor of the month. 



a. The tongue is an elongated muscular mass, attached 



along the greater part of its length to the floor 

 of the mouth, and produced in front into a free 

 flattened tip. 



The surface of its hinder part is hard and 

 sUghtly elevated; that of the anterior part is 

 softer and dotted over with small white papiUse, 

 which are especially numerous at and under 

 the tip. 



At the sides of the tongue, opposite the last 

 molar teeth, are a pair of oval patches, the 

 papillae foliatae, the surfaces of which are crossed 

 obliquely by close-set parallel ridges, in which are 

 imbedded numerous taste-bulbs. 



About a quarter of an inch above and behind 

 the papiUse foliatae are a pair of circnmvallate 

 papillae, which are small and white, and sur- 

 roimded by circular grooves. 



b. The lower teeth, already described with the skeleton 



(p. 284), are placed opposite the corresponding 

 teeth of the upper jaw, and bite against them. 



