INSALIVATION. 107 



when the animal was restored to its owner, the food again 

 pierced through the soft tissues, and threatened to render the 

 case a hopeless ona I cast the horse, cleaned out the accu- 

 mulated matter, and carefully moulded gutta percha in the 

 space left from which the molar had been extracted, and at 

 the same time plugged an adjoining carious tooth; the mould 

 was made on a level with the row of molars, and I have since 

 traced the horse, obtaining most satisfactory evidence of the 

 success attending the simple plan which I was induced to 

 adopt. Corks and other objects have been pressed between 

 the teeth for the purpose of filling a void; but no method, 

 so far as I am aware, has succeeded like the gutta percha 

 plug. 



INSALIVATION. 



Whilst food is being triturated, it is mixed thoroughly 

 with the secretions in the mouth. The mucus, which is 

 very small in quantity when the flow of saliva is rapid, 

 is an acid liquid mixed with scaly epithelium, and seems 

 to exert very slight influence in the changes which the food 

 undergoes in the mouth. A considerable quantity of mucus 

 is secreted from the mucous crypts, which consist in small 

 depressions on the mucous membrane like little bags, and 

 the walls of which have openings communicating with 

 rounded vesicles. Some are spread, such as over the surface 

 of the tongue, and others are congregated, as on the side of 

 the throat, constituting the amygdalce or tonsils. 



The most important physical and chemical transformations 

 occur by the process of 



INSALIVATION. The salivary glands are important organs, 

 composed of tubular prolongations of the mucous membrane 

 of the mouth, and which are of different degrees of complex- 



