474 OP THE THROAT. 



CHAPTER XIV. 



OF THE THROAT. 



To avoid circumlocution, the word throat is used as a 

 general term to comprehend the structure which occurs behind 

 the nose and mouth, and above the oesophagus and trachea. 

 This structure consists, 



1st. Of the parts immediately behind the mouth, which con- 

 stitutes the Isthmus of the Fauces : 



2d. Of the parts which form the orifice of the windpipe, or 

 the Larynx ; — and 



3d. Of the muscular bag, which forms the cavity behind the 

 nose and mouth, that terminates in the oesophagus or the 

 Pharynx. 



Of the Isthmus of the Fauces. 



In the back part of the mouth, on each side, are to be seen 

 the tw^o ridges or half arches, passing from the soft palate to 

 the root of the tongue, (see fig. 118, p. 454,) formed by plaits 

 of the mucous membrane, containing muscular fibres. The 

 anterior plait, which contains the muscle called Constrictor 

 Isthmi Faucium, passes directly from the side of the root of 

 the tongue to the palate, and terminates near the commence- 

 ment of the uvula. The posterior plait runs from the palate 

 obliquely downwards and backwards, as it contains the palato- 

 pharyngeus muscle, which passes from the palate to the upper 

 and posterior part of the thyroid cartilage. 



In the triangular space between these ridges is situated a 

 glandular body, called the Tonsil or Amygdala.* This gland 



* It is named amygdala, from its resemblance in form and appearance to an 

 almond covered by its shell. The exterior or adhering surface of the tonsil 

 gland is connected by the means of cellular tissue to the superior constrictor 

 muscle of the pharynx. 



The internal carotid artery is situated behind and to the outer side of the 

 tonsil, and separated from it only by the constrictor muscle, and cellular tissue. 



It has been wounded in opening abscesses of the tonsils, when the cutting 

 instrument has been inclined too much outwards and backwards. — p. 



