548 



THE ARTERIES. 



deeply seated, being covered by the integument, superficial fascia, Platysma, and 

 deep cervical fascia, the Sterno-mastoid, Sterno-hyoid, and Sterno-thyroid muscles, 

 and by the Omo-hyoid, opposite the cricoid cartilage ; but in the upper part of its 

 course, near its termination, it is more superficial, being covered merely by the 

 integument, the superficial fascia, Platysma, deep cervical fascia, and inner margin 

 of the Sterno-mastoid, and is contained in a triangular space, bounded behind by 



FIG. 348. Plan of the 

 branches of the external 

 carotid. 



FIG. 347. Surgical anatomy of the arteries of the neck. Right side. 



the Sterno-mastoid, above by the posterior belly of the Digastric, and below by 

 the anterior belly of the Omo-hyoid. This part of the artery is crossed obliquely, 

 from within outward, by the sterno-mastoid artery ; it is crossed also by one, or 

 sometimes two superior thyroid veins, which terminate in the internal jugular ; 

 and, descending on its sheath in front, is seen the descendens hypoglossi nerve, 

 this filament being joined by one or two branches from the cervical nerves, which 

 cross the vessel from without inward. Sometimes the descendens hypoglossi is 

 contained within the sheath. The middle thyroid vein crosses the artery about 



