710 



ORGANS OF DIGESTION. 



cularis Oris, round the orifice of the mouth. They are rounded in form, about 

 the size of small peas, 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 

 membrane, and between the two, of a muscular stratum, besides a large quan- 

 tity 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 

 which presents the aperture of the duct of the parotid gland. The principal 

 muscle of the cheek is the Buccinator ; but several other muscles enter into 

 its formation ; viz., the Zygomatici, Masseter, and Platysma Myoides. 



Fig. 384. Sectional View of the Nose, Mouth, Pharynx, &c. 



The buccal glands are placed between the mucous membrane and Buccinator 

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

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

 cinator 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. 

 They are covered by smooth and vascular mucous membrane, which is re- 

 markable for its limited sensibility. Around the necks of the teeth, this mem- 

 brane presents numerous fine papilla ; and from this point it is reflected into 

 the alveolus, where it is continuous with the periosteal membrane lining that 

 cavitv. 



