Page:Structure and functions of the body; a hand-book of anatomy and physiology for nurses and others desiring a practical knowledge of the subject (IA structurefunctio00fiskrich).pdf/68

 The parotid gland is the largest and is below and in front of the ear, opening by Stensen's duct. The ''submaxillary gland'' is below the jaw toward the back on either side and its duct is Wharton's duct. The sublingual gland lies beneath the mucous membrane of the floor of the mouth and opens by eight to twenty tiny ducts beside the frenum, the ducts of Rivinus. The activity of the glands depends upon the blood supply; the more blood the greater their activity.

—Dissection of the side of the face, showing the salivary glands: a, Sublingual gland; b, submaxillary gland, with its duct opening on the floor of the mouth beneath the tongue at d; c, parotid gland and its duct, which opens on the inner side of the cheek. (After Yeo.)

The Tonsils.—The tonsils vary in size and in tonsillitis swell and may even meet in the median line. They are frequently removed. When they are enlarged one often gets a third tonsil or adenoids, a lymphoid growth at the back of the pharynx which causes mouth-breathing by day and snoring by night. A child with adenoids is starved for air and what air is breathed in is not warmed. The growth should be removed.

A short frenum produces tongue-tie, which may be remedied by snipping. Cancer of the tongue is fairly common and necessitates a radical operation. In mumps the parotid glands are inflamed and enlarged.