PHARYNX 383 



Vessels and Nerves of the Soft Palate. The ascending 

 palatine branch of the external maxillary artery is, as a rule, 

 the principal artery of supply to the soft palate. It has 

 already been traced on the wall of the pharynx (p. 299), 

 where it lies in the sinus of Morgagni, in relation to the 

 levator palati muscle, which it accompanies into the soft palate. 

 The palatine branch of the ascending pharyngeal artery may 

 also be traced into the soft palate. In cases where the 

 preceding artery is small, this twig will be found enlarged 

 so as to take its place (p. 304). The descending palatine 

 branch of the internal maxillary artery also sends small twigs 

 to the soft palate and tonsil. 



Two nerves enter the soft palate from the spheno-palatine ganglion viz. 

 the posterior palatine and the middle palatine nerve. It would appear, 

 however, that they do not supply the muscles, but are distributed to the 

 mucous membrane. The levator palati, the musculus uvulae, the glosso- 

 palatinus, and the pharyngo-palatinus are supplied by twigs from the 

 pharyngeal branches of the vagus, which convey to them fibres which are 

 originally derived from the cerebral part of the accessory nerve (v. p. 315) 

 (W. Aldren Turner). The tensor palati is probably supplied by the 

 branch which it receives from the otic ganglion, which conveys to it fibres 

 originally derived from the motor part of the trigeminal nerve. 



Tonsillae PalatinsB. The palatine tonsils are two prominent 

 masses of lymphoid tissue, placed one on each lateral wall 

 of the pharynx, in the triangular interval between the two 

 palatine arches and immediately above the pharyngeal part 

 of the tongue. The pharyngeal or internal surface of the 

 tonsil is covered with mucous membrane and presents a 

 number of orifices which lead into crypts or recesses in its 

 substance. The deep or external surface is embedded in the 

 pharyngeal wall and is supported by the superior constrictor 

 muscle of the pharynx (see p. 298). It is covered by a layer 

 of fibrous tissue which forms an incomplete capsule for the 

 organ. It is important to note that between the tonsil and 

 the superior constrictor there is some lax connective tissue, so 

 that the organ can be pulled forwards by the volsellum with- 

 out dragging the wall of the pharynx with it. 



The tonsils have a rich blood-supply. They derive arterial 

 twigs from the tonsillar and ascending palatine branches of 

 the external maxillary, the descending palatine branch of the 

 internal maxillary, the ascending pharyngeal, and the dorsalis 

 linguae. 



Tuba Auditiva (O.T. Eustachian Tube). This is the 



