106 OUR BODIES AND HOW WE LIVE 



The parotid gland lies below and in front of each ear. 1 



The submaxillary gland is under the lower jaw. 



The sublingual gland is found under the tongue, in the 

 floor of the mouth. 



Each salivary gland opens into the mouth by a little duct. 

 Each has a certain resemblance to a bunch of grapes, 

 with a tube for a stalk. 



151. The Action of Saliva. Saliva flows rapidly into 

 the mouth while we are chewing food. About two pints 

 of saliva are secreted in the course of a day. Sometimes 



ABC D 



FIG. 68. Diagram of the Structure of 

 Secreting Glands. 



A, simple tubular gland; B, gland with mouth shut and sac formed; C, gland 

 with a coiled tube ; >, plan of part of a racemose gland. 



these glands are busily at work even before we actually 

 taste food. The saliva will flow into the mouth even at 

 the sight, smell, or thought of food. This is commonly 

 known as " making the mouth water." 



The saliva mixes with food and softens it, and aids in 

 speech by keeping the mouth moist. It also acts upon the 

 starchy matters in food through its ferment, called ptyalin, 

 and changes them into a form of sugar known as maltose. 



Experiment 30. To make the saliva flow. Think of some favorite 

 article of food, and note the flow of saliva. Push a lead pencil or the 

 finger to and fro in the mouth several times, and note the flow of saliva. 



1 This gland, especially in childhood, sometimes becomes inflamed and 

 swollen in the disease familiarly known as " mumps." 



