146 VISCERAL ANATOMY. 



What Nerves are distributed to the Tongue ? The 



Gustatory Branch of the ^th, to the mucous membrane of the sides and 

 anterior two- thirds of the tongue, endowing it with general sensibility. 



Chorda Tympani Branch of the jth, joins the gustatory, and is distributed 

 to the same region, being the nerve of taste for the anterior two-thirds of the 

 tongue. 



Lingual Branches of the gth or Glosso-pharyngeal, to the mucous membrane 

 of the base and sides of the tongue, being the nerve of taste for its poste- 

 rior third. 



Hypoglossal, or i2th, to the intrinsic and extrinsic muscles of the tongue, 

 being its nerve of motion. 



Superior Laryngeal Branch of the loth or Pneumogastric , sends a few 

 fibres to the base of the tongue from its internal branch. 



What special Anatomical Features are presented by the MouLh ? 

 They are as follows, viz. the 



Hamular Process of the Sphenoid Bone, may be felt behind the last upper 



molar tooth ; also the Internal Pterygoid Plate, and part of the Pterygoid 



Fossa. 



Coronoid Process, of the lower jaw, its anterior border. 

 Posterior Palatine Artery, at inner side of the last upper molar tooth, and 



in front of the hamular process. 



Gustatory Nerve, very near the last lower molar tooth. 

 Pterygo-maxillary Ligament, felt as a fold posteriorly to the last lower 



molar tooth. 



THE PHARYNX. 



Describe the Pharynx. It is a conical, musculo-membranous bag, about 

 4^ inches long, hung base up from the basilar process of the occipital bone, 

 and extending to the lower border of the cricoid cartilage posteriorly, or the 

 5th cervical vertebra, where it becomes continuous with the oesophagus. 5 It 

 forms the part of the alimentary canal which lies behind the mouth, being 

 incomplete in front. 



What are its Relations ? It is connected with 

 Posteriorly, the longus colli and recti capitis antici muscles, and by loose 



areolar tissue to the first 5 cervical vertebrae. 

 Laterally, the styloid processes and their muscles, the pterygoid muscles, the 



internal carotid arteries, the internal jugular vein, the 8th, pth, and the 



sympathetic nerves. 

 Near its Apex, the lobes of the thyroid gland, the common carotid and 



lingual arteries, the sterno-hyoid muscle, and the lingual nerves. 



