THE HEAD AXD NECK 297 



the terminal portion of the parotid duct to a position 

 dorsal to the angle of the mouth. 



{k) The larger inferior buccal gland is also elongate but thicker, 

 and comprises three portions. Two long, slender masses 

 lie side by side internal to the more ventral part of the 

 buccinator muscle, which must be cut lengthwise to expose 

 them. The thicker, more dorsal of the two is replaced 

 caudally by a third portion which has received the name 

 masseteric gland. 



(/) The superficial mandibular gland, a flattened, oval mass 

 closely applied to the ventrolateral surface of the mandible, 

 covered by the anterior part of the platysma, is a cutaneous 

 gland, from which the ducts open on the skin of the lower 



lip. 



(m) The facial lymph gland overlies the dorsal edge of the 

 buccinator muscle and is covered laterally by the zygo- 

 maticus minor. 



3. Dissection on the ventral surface of the neck to free the ex- 

 ternal jugular vein and its tributaries. The cervical fascia and 

 a portion of the parotid gland must be removed. 

 The external jugular vein (v. jugularis externa) is formed be- 

 hind the angle of the mandible by the union of the anterior and 

 posterior facial veins. It passes backward in a superficial position 

 to the superior thoracic aperture. Its connections in the lower part 

 of the neck comprise the transverse scapular vein (v. transversa 

 scapulae) of the shoulder and its union with the vein of the other 

 side by the transverse jugular vein (v. jugularis transversa) 

 (Fig. Ill, p. 327). The last-mentioned vessel crosses ventral to the 

 common carotid artery and the sternohyoid muscle a short distance 

 anterior to the tip of the manubrium sterni. 



The posterior facial vein is formed in front of the base of the 

 ear by the union of the superficial temporal vein, which runs 

 forward immediately dorsal to the external auditory meatus after 

 emerging from the cranial cavity, and the external ophthalmic 

 vein, which passes back from the orbit. 



The superficial temporal vein receives blood from the brain through the 

 transverse sinus, which emerges through a foramen between the squamosal and 



