The anterior facial begins over the frontal bone caudad of the orbit, where it is known as the frontal vein (c″). This runs along the dorsal border of the orbit, into which it dips. It sends a communicating branch into the orbit, and receives small veins (superior palpebral) from the upper eyelid. It then turns ventrad, passing along the cranial angle of the eye between the levator labii superioris proprius (5) and the orbicularis oculi (8) muscles, being called in this region the angular vein (c′). This receives branches (external nasal veins, k) from the side of the nose. The vein crosses the malar bone obliquely (now receiving the name anterior facial, c) and follows the cranioventral border of the masseter muscle (9). As it passes the infraorbital foramen it receives through the foramen a small vein from within the orbit. It receives also the inferior palpebral (j) from the lower eyelid, and the superior labial vein (i) from the upper lip. Just caudad of the angle of the mouth it receives from beneath the cranioventral margin of the masseter the V. facialis profunda (h) [described] below. Still farther caudad it receives the inferior labial vein (g) from the lower lip, and a small branch from the masseter muscle. Caudad of the middle of the cranioventral border of the masseter it receives from beneath the lymphatic gland of this region the large submental vein (f). Next the anterior facial vein receives a large communicating branch (V. transversa, d) which passes transversely across the ventral surface of the throat and connects the two anterior facial veins of the opposite sides. From the middle of this communicating branch an unpaired trunk passes caudad in the middle line and divides into the two laryngeal veins, which pass to the larynx; a small branch is continued from the unpaired trunk craniad into the tongue. The communicating branch receives also near its junction with the anterior facial a rather large superficial branch (e) which comes from the sides of the lower jaw and passes across the lymphatic gland (12) to join the communicating branch.

[Fig. 131].—Superficial Veins and Arteries of the Face.

a, external jugular vein; b, posterior facial vein; c, anterior facial vein (c′, angular vein; c″, frontal vein); d, communicating branch with opposite anterior facial; e, superficial branch from lower jaw; f, submental vein; g, inferior labial vein; h, deep facial vein; i, superior labial vein; j, inferior palpebral vein; k, external nasal veins; l, posterior auricular vein; m, superficial temporal vein; n, anterior auricular vein; o, external maxillary artery; p, inferior labial artery; q, superior labial artery; r, infraorbital arteries; s, superficial temporal artery; u, anterior auricular branch of posterior auricular artery. 1, M. adductor auris superior; 2, M. corrugator supercilii medialis; 3, M. corrugator supercilii lateralis; 4, M. levator labii superioris alæque nasi; 5, M. levator labii superioris proprius; 6, M. myrtiformis; 7, M. orbicularis oris; 8, M. orbicularis oculi; 9, M. masseter; 10, parotid gland; 11, submaxillary gland; 12, lymphatic glands.

The following larger branches of the anterior facial are not described above:

V. facialis profunda ([Fig. 131], h).—The deep facial vein enters the anterior facial from beneath the masseter, just caudad of the angle of the mouth. It collects branches from the soft and hard palates and the teeth, these branches passing along with the corresponding arteries for a distance, then uniting and passing ventrolaterad beneath the zygomatic arch to join the anterior facial. The deep facial vein also receives branches which come from the venous plexus that lies in the same region as the arterial carotid plexus.

V. submentalis ([Fig. 131], f).—This enters the anterior facial vein at the ventral border of the masseter muscle and near the cranial end of the two superficial lymph-glands (12) in this region. The submental vein is formed at the dorsal border of the digastric muscle by two branches emerging from between the digastric and the mandible. The more cranial of these, V. lingualis, collects branches from the tongue, from its middle to the tip; it passes through the middle of the lateral border of the mylohyoid muscle to join the other branch. The second branch emerges from between the mandible and the pterygoid muscles. It comes from near the caudal end of the mandible, where it becomes continuous with a communicating branch from the posterior facial vein, and receives a branch which comes from the mandibular canal; also small branches from the adjacent parts.

e. V. facialis posterior ([Fig. 131], b).—The posterior facial vein arises from the region of the internal maxillary artery, its terminal branches following the branches of the artery. It collects blood from the pterygoid, masseter (9), and temporal muscles, and forms a plexus which is interwoven with the carotid (arterial) plexus in the region of the orbital fissure. It is connected with the submental vein by a communicating branch. From the posterior facial a branch extends ventrad close against the outer surface of the tympanic bulla and then turns caudad, receives a branch from the pharynx, then continues to join the internal jugular. The posterior facial itself passes laterad along the caudal border of the masseter (9) and the ventral border of the parotid gland (10), then becomes superficial and turns ventrad over the outer surface of the submaxillary gland (11) to join the anterior facial (c) caudad of the angle of the jaw.

As it passes ventrad of the parotid gland (10), just before becoming superficial, the posterior facial receives the superficial temporal (m). This at first follows the superficial temporal artery (s), then enters the substance of the parotid gland, joining the posterior facial near the ventral border of the latter. The superficial temporal receives the anterior auricular (n), a large vein passing along the cranial border of the auricular opening and arising dorsad of the eye.

The posterior facial receives also, at the point where it passes from beneath the parotid gland, the posterior auricular or great auricular vein (l). This collects blood from the back of the head and the external ear, its branches following those of the artery of the same name. It passes along the caudal border of the parotid gland to join the posterior facial.