DISSECTION OF THE NECK. 6j 



enveloping the pharynx. It supplies the tongue and 

 pharynx with sensory fibres, and gives some motor 

 fibres also to the pharynx. 



15. The Lingual Nerve. If not previously done, 

 cut through the mylo-hyoid muscle ; the lingual will 

 be exposed coming out from under the mandible. It 

 runs toward the mid-line and disappears in the tongue, 

 which it supplies with gustatory fibres. This nerve is 

 a branch of the inferior maxillary division of the 5th 

 or trigeminal nerve. 



Continue the dissection of the vagosympathetic 

 trunk posteriorly. In order to show the relations of 

 this ti'unk at the root of the neck and in the thorax, 

 open the latter freely, as in the dissection of the thoracic 

 viscera, double-ligature the large veins at the root of 

 the neck, divide them between the ligatures, and then 

 dissect out the vagosympathetic trunk. 



16. Inferior Cervical Ganglion. At the root of the 

 neck the vago-syrfipathetic ends in a large ganglion, 

 the inferior cervical ganglion, from which several 

 small branches are given off, passing toward the heart 

 and entering the cardiac plexus. At the ganglion 

 the two nerves separate as shown in Fig. 6. 



17. The Thoracic Vagus continues posteriorly from 

 the ganglion, giving off also some small branches to 

 join the cardiac plexus. Near the base of the heart it 

 gives off a large branch, the recurrent or inferior lary^t- 

 geal, which on the left side curves round the aorta and 

 passes anteriorly along the side of the trachea in the 

 neck, where it can easily be found and followed to its 

 termination in the larynx, to the muscles of which it 

 gives motor fibres. Dissect out the communicating 

 branch to the superior laryngeal which passes beneath 

 the wing of the thyroid cartilage. On the right side 



