334 THE HUMAN BODY. 



posed to be concerned in the sense of taste, and hence called 

 the taste-buds (Chap. XXXV). The fungiform papillcB, 3, 

 are rounded elevations attached by somewhat narrowed stalks, 

 and found all over the middle and fore part of the upper 

 surface of the tongue. They are easily recognized on the 

 living tongue by their bright red color. ^\^Q filiform papillae, 

 most numerous and smallest, are scattered all over the dorsum 

 of the tongue except near its base. Each is a conical emi- 

 nence covered by a thick horny layer of epithelium. It is 

 these papillae which are so highly developed on the tongues 

 of Carnivora, and serve them to scrape bones clean of even 

 such tough structures as ligaments. 



In health the surface of the tongue is moist, covered by 

 little " fur," and in childhood of a red color. In adult life 

 the natural color of the tongue is less red, except around the 

 edges and tip; a bright-red glistening tongue being then, 

 usually a symptom of disease. When the digestive organs 

 are deranged the tongue is commonly covered with a thick 

 yellowish coat, composed of a little mucus, some cells of 

 epithelium shed from the surface, and numerous microscopic 

 organisms known as bacteria; and there is frequently a " bad 

 taste in the mouth." The whole alimentary mucous mem- 

 brane is in close physiological relationship; and any thing' 

 disordering the stomach is likely to produce a "furred 

 tongue." 



The Salivary Glands. The saliva, which is poured into 

 the mouth and which, mixed with the secretion 'of minute 

 glands imbedded in its lining membrane, moistens it, is 

 secreted by three pairs of glands, the parotid, the submaxil- 

 lary and the suUingual. The parotid glands lie in front of 

 the ear behind the rarnus of the lower jaw; each sends its 

 secretion into the mouth by a tube known as 8 tenon's duct, 

 which crosses the cheek and opens opposite the second upper 

 molar tooth. In the disease known as mumps * the parotid 

 glands are inflamed and enlarged. The subm axillary glands 

 lie between the halves_of the lower |aw-bope, near its angles, 

 and their ducts open beneath the tongue near the middle line. 

 The sublingual glands lie beneath the floor of the month, 

 covered by its mucous membrane, between the back part of 

 the tongue and the lower jaw-bone. Each has many ducts 



* Parotitis, in technical language. 



