The Neck. 481 



hvo-glossus muscle, by a curved incision, with convexity 

 downwards, starting a little below and external to the 

 symphysis of the jaw and ending a little below and to the 

 inner side of where the facial artery crosses the inferior 

 maxilla. The centre of the incision will be opposite the 

 greater cornu of the hyoid bone. After division of the 

 integument, superficial fascia and platysma muscle, the 

 submaxillary gland is identified, the deep fascia overlying 

 it is divided, and the gland elevated and held up by a re- 

 tractor. The fascia exposed beneath thi's gland is incised, 

 the mylo-hyoid muscle at the anterior angle of the 

 wound, and the tendon uniting the two bellies of the di- 

 gastric at the central part of the wound, defined. The 

 hypoglossal nerve is now sought for, where it crosses the 

 hyo-glossus muscle, on which, both it and the digastric 

 rest, and, when found, there is seen a triangle with this 

 nerve as the base and the bellies of the digastric as the sides. 

 Running across this triangle, about midway between 

 apex and base, is the ranine vein, the situation of which 

 corresponds to that of the lingual artery, separated from 

 it, however, by the hyo-gilossus muscle. This vein is dis- 

 placed upwards and the underlying muscle divided, trans- 

 versely, at the point on which the vein previously rested, 

 when the artery will be exposed, accompanied by two 

 small venae comites, which will, in all probability, be in- 

 cluded in the ligature. 



Nerves. The facial has been stretched for the relief 

 of uncontrollable spasms of the muscles of the face, and 

 the incision for this operation starts at the root of the mas- 

 toid process and ends near the angle of the jaw. The 

 parotid gland and the anterior edge of the sterno-mastoid 

 muscle are identified. These are separated from each 

 other, the former being drawn forwards, and the latter, 

 backwards, the posterior belly of the digastric is exposed 



