DISSECTION OF THE NECK. 67 
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 dadzssection of the vago-sympathetic 
trunk posteriorly. In order to show the relations of 
this trunk at the root of the neck and in the thorax, 
open the latter freely, as in the dissection of the thoracic 
vescera, double-ligature the large vetns at the root of 
the neck, divide them between the ligatures, and then 
dissect out the vago-sympathetic trunk. 
16. Inferior Cervical Ganglion. At the root of the 
neck the vago-sympathetic ends in a large ganglion, 
the zzferzor 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 alarge branch, the recurrent or tnfertor laryn- 
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 
