DIGESTION AND ABSORPTION. 105 



THE SALIVARY GLANDS. 



24, In health, the mouth is always moist. When we 

 taste any good thing, or even think of it, the "mouth 

 waters." This water is the saliva, or spittle ; and most of 

 it comes from bodies called the salivary glands. 



25, There are three pairs of these glands, two parotid 

 glands, two submaxillary glands, and two sublingual 

 glands. 



The parotid gland is the largest, and is situated just 

 under the ear. Mumps is an inflam- 

 mation of this gland, which makes 

 it swell, and the neighboring parts 

 of the neck with it. 



The submaxillary gland is next in 

 size, and lies behind the edge of the 

 under jaw beneath the floor of the 

 mouth. 



The sublingual gland lies farther 

 forward than the submaxillary, also Fi 4Q 



Under the floor Of the inOUtll. A portion of the Parotid gland, 



26, When these glands are exam- magnified. 



ined with the aid of a microscope, they are seen to consist 

 of tubes, large and small, with little sacs on the end of 

 them. They may be compared to a mass of cherries on 

 a branch, or bunches of grapes pressed together. Small 

 blood-vessels penetrate the mass, and surround the tubes 

 and the sacs. Water and other substances pass from the 

 blood through the walls of the blood-vessels, and into the 

 sacs, to make the saliva. As the sacs and tubes get full, 

 the saliva flows from the small tubes into larger ones, and 

 then into still larger ones, and, finally, it is all collected 



