382 



THE DIGESTIVE SYSTEM 



THE SALIVARY GLANDS 



General Considerations. The salivary or oral glands include the 

 smaller glands of the oral cavity and three pairs of large compound 

 tubulo-acinar glands, the parotid, submaxillary, and sublingual glands. 



The three large pairs are commonly 

 designated as the salivary glands 

 proper, the smaller as the accessory 

 salivary glands. All these are of the 

 tubulo-acinar type, but certain ones 

 secrete a mucous fluid while others pro- 

 duce an albuminous secretion which 

 contains no mucus. The former are 

 known collectively as the mucous, the 

 latter as the serous salivary glands. 

 Still other salivary glands secrete a 

 fluid which is intermediate in compo- 

 sition, and as these glands contain cer- 

 tain alveoli which resemble those of 

 the mucous, and others which are sim- 

 ilar to those of the serous glands, this 

 type is known as mixed salivary 

 glands. 



The salivary glands may therefore 

 be subdivided into: 



I. Mucous glands; glands on the 

 anterior surface of the hard and soft 

 palate (palatine glands) and the mu- 

 cous glands of the margins and root of 

 the tongue. 



II. Mixed glands; submaxil- 

 lary, sublingual, molar, buccal, labial 

 and the anterior lingual glands (of 

 Xuhn). 



III. Serous glands; parotid, and von Ebner's glands at the base 

 of the tongue. 



The form of the salivary glands will be appreciated by examination 

 of the accompanying diagram (Fig. 353) which represents one of the 

 smaller glands of this type. The larger ones are constructed in the 



FIG. 353. SEMIDIAGRAMMATIC REP- 

 RESENTATION OF A SMALL Mu- 

 cous GLAND FROM THE ORAL 

 MUCOSA OF A RABBIT. 



a, mucous alveoli; e, epithelium 

 of the oral mucosa; m, mouth of 

 the glandular duct. X 70. (After 

 Kolliker.) 



