762 f THE VASCULAR SYSTEM. 
lower lip, supplying the skin, muscles, and mucous membrane, and anastomoses with the 
mental branch of the inferior dental, with the inferior coronary, with the submental, and 
with its fellow of the opposite side. 
(f) The inferior coronary springs from the front of the facial artery, either 
together with or directly above the inferior labial branch. It runs forwards beneath the 
depressor anguli oris, and between the fibres of the orbicularis oris and the mucous mem- 
brane of the lip. It supplies the adjacent parts, and anastomoses with its fellow of the 
opposite side, and with the mental, inferior labial, and submental arteries. 
(7) The superior coronary (a. labialis superior) springs from the front of the facial 
beneath the zygomaticus major, and runs forwards and inwards between the orbicularis 
oris and the mucous membrane of the upper lip to the middle line. It supplies 
the skin, muscles, and mucous membrane of the upper lip, and the lower and front part of 
the septum of the nose, by a septal branch which runs upwards on the anterior part of the 
nasal septum. It anastomoses with its fellow of the opposite side, with the lateral nasal, 
and, on the septum nasi, with the naso-palatine branch of the spheno-palatine artery. 
(hk) The masseteric branch, sometimes represented by several twigs, arises from the 
posterior aspect of the facial trunk a short distance above the lower margin of the jaw. It 
passes upwards and backwards across the masseter, and anastomoses with the transverse 
facial artery. 
(¢) The buccal is an inconstant branch which, when present, arises from the back of 
the facial artery above the masseteric branch and runs upwards and backwards, across the 
buccinator muscle, to anastomose with the buccal branch of the internal maxillary artery. 
(<) The lateral nasal, one of the terminal branches of the facial artery, is usually 
small. It ramifies on the ala of the nose, supplying the skin, muscles, and lower 
lateral cartilages, and anastomosing with the angular branch, with the nasal branch of the 
ophthalmic, and with branches of the spheno-palatine artery. 
(1) The angular (a. angularis), the other terminal branch of the facial, continues 
the direction of the main trunk along the side of the nose to the inner angle of the 
orbit. It supplies the skin and muscles of the side of the nose, and anastomoses with the 
lateral nasal, and with the nasal and palpebral branches of the ophthalmic artery. 
(4) Occipital Artery (a. occipitalis, Figs. 554, 555, and 582).—This vessel arises 
from the back of the external carotid artery, below the posterior belly of the 
digastric muscle, and terminates near the inner end of the superior curved line 
of the occipital bone by dividing into internal and external terminal branches. 
Course.—It commences in the carotid triangle and runs upwards and back- 
wards, parallel with and under cover of the posterior belly of the digastric, to the 
interval between the transverse process of the atlas and the base of the skull, where 
it turns backwards in a groove on the under surface of the mastoid portion of the 
temporal bone; as it leaves the groove it alters its direction and runs upwards 
and inwards on the superior oblique muscle to the junction of the inner and 
middle thirds of the superior curved line of the occipital bone, where it enters the 
superficial fascia of the scalp. 
Relations.—In the first or ascending part of its course the occipital artery crosses 
successively the internal carotid artery, the hypoglossal nerve, the vagus nerve, the internal 
jugular vein, and the spinal accessory nerve; it is covered by the lower fibres of the 
posterior belly of the digastric and the anterior part of the sterno-mastoid muscle and, 
close to its origin, it is crossed by the hypoglossal nerve. In the second, or more 
horizontal part of its course, it is still under cover of the sterno-mastoid and digastric, 
and lies internally against the rectus capitis lateralis, which separates it from the 
vertebral artery. In the third part of its course it rests upon the superior oblique 
and complexus, and is under cover of the sterno-mastoid, the splenius capitis, and the- 
trachelo-mastoid muscles. At its termination it is crossed by the great occipital nerve ; 
it passes either through the trapezius or between the trapezius and the sterno-mastoid, 
and pierces the deep fascia of the neck before it enters the superficial fascia of the scalp. 
Branches.—(«) Muscular branches (rami musculares) go to the surrounding muscles. 
The sterno-mastoid branch (a. sternocleido-mastoidea) is the most important of this group ; 
it springs from the commencement of the occipital, is looped downwards across the hypo- 
glossal nerve, and is continued downwards and backwards, below and in front of the 
spinal accessory nerve, into the sterno-mastoid muscle where it anastomoses with the 
sterno-mastoid branch of the superior thyroid artery. 
(4) The meningeal are irregular branches (rami meningei) given off from the occipital 
| 
| 
| 
