644 



ORGANS OF DIGESTION. 



oris, round the orifice of the mouth. They are rounded in form, about the size 

 of a small pea ; their ducts opening by small orifices upon the mucous membrane. 

 In structure, they resemble the other salivary glands. 



The CHEEKS form the sides of the face, and are continuous in front with the 

 lips. They are composed, externally, of integument ; internally, of mucous mem- 

 brane ; and, between the two, of a muscular stratum, besides a large quantity of 

 fat, areolar tissue, vessels, nerves, and buccal glands. 



The mucous membrane lining the cheek is reflected above and below upon the 

 gums, and is continuous behind with the lining membrane of the soft palate. 

 Opposite the second molar tooth of the upper jaw is a papilla, the summit of 



Fig. 319. Sectional View of the Nose, Mouth, Pharynx, etc. 



which presents the minute aperture of the duct of the parotid gland. The prin- 

 cipal muscle of the cheek is the Buccinator ; but numerous others enter into its 

 formation, viz., the Zygomatici, Masseter, and the Platysma myoides. 



The buccal glands are placed between the mucous membrane and Buccinator 

 muscle: they are similar in structure to, but smaller than, the labial glands. Two 

 or three, of larger size than the rest, are placed between the Masseter and 

 Buccinator muscles; their ducts open into the mouth, opposite the last molar 

 tooth. They are called molar glands. 



The GUMS are composed of a dense fibrous tissue, closely connected to the 

 periosteum of the alveolar processes, and surrounding the necks of the teeth. 



