476 Anatomy Applied to Medicine and Sutgery. 



Landmarks for the Bloodvessels. The course 

 of the common, external and internal carotid arter- 

 ies, when the face is slightly turned to the opposite side, 

 may be represented by a line drawn from the sterno- 

 clavicular articulation, to a point midway between the 

 angle of the jaw and the tip of the mastoid process of the 

 temporal bone. The portion of this line below the level 

 of the upper border of the thyroid cartilage corresponds 

 to the common carotid artery; the portion, above this 

 level, agrees with the situation of the internal carotid, 

 while the line for the external carotid should be drawn 

 slightly in front of that for the internal carotid. Superior 

 thyroid artery. The line for this vessel begins at the line 

 for the external carotid, just below the level of the tip of 

 the greater cornu of the hyoid bone, and passes in a curved 

 direction, with convexity forwards, to the upper part of 

 the thyroid gland. The line for the lingual starts from 

 the line for the external carotid, opposite the tip of the 

 greater cornu of the hyoid bone, and, passing above the 

 latter, runs parallel to it for a short distance and then up- 

 wards to the junction of the anterior and middle thirds of 

 the lower border of the jaw. Facial. The line for this 

 vessel starts at the line for the external carotid, about 

 one-quarter of an indh above the tip of the greater cornu 

 of the hyoid bone, and runs, in a curved manner, to the 

 junction of the anterior edge of the masseter muscle with 

 the lower border of the jaw. The occipital line begins at 

 a point opposite the commencement of the line for the 

 facial and runs to the tip of the mastoid process, and 

 thence to about midway between the occipital protuber- 

 ance and the posterior border of the mastoid. 



The subclavian artery may be represented by an arched 

 line, running from the sterno-clavicular articulation to a 

 point, a little to the inner side of the middle of the clavicle, 



