CUTANEOUS ARTERIES. 503 



carotid ; while three, viz., the superficial temporal, the occipital, 

 and the posterior auricular, are derived from the external. 



The SUPRAORBITAL ARTERY leaves the orbit through the notch Supraorbi- 

 in the margin of the orbit, and is distributed on the forehead. ^ l arter y 

 Some of its branches are superficial to the frontalis and supply the 

 skin ; while others lie beneath the muscle, and supply it, the 

 pericranium, and the bone. 



The FRONTAL ARTERY is close to the inner angle of the orbit, Frontal 

 and is much smaller than the preceding. It ends in branches for arter y- 

 the supply of the muscles, integuments, and pericranium. 



The SUPERFICIAL TEMPORAL ARTERY (d) IS One of the terminal Superficial 



branches of the external carotid. After crossing the zygoma 

 immediately in front of the ear, the vessel divides on the temporal 

 fascia into anterior and posterior branches. 



The anterior branch runs forward with a serpentine course to anterior an<J 

 the forehead, supplying muscular, cutaneous, and pericranial offsets, 

 and anastomoses with the supraorbital artery ; this is the branch 

 that is opened when blood is taken from the temporal artery. 



The posterior branch is larger than the other, and ascends to the posterior 

 top of the head, over which it anastomoses with the artery of the branches - 

 opposite side. Its offsets are similar to those of the anterior 

 division, and communicate behind with the occipital and posterior 

 auricular arteries. 



OCCIPITAL ARTERY. The terminal part of this artery, Occipital 

 appearing between the trapezius and sterno-mastoid muscles, artery ' 

 divides into large and tortuous branches, which spread over the 

 back of the head. Communications take place with the artery of 

 the opposite side, with the posterior branch of the temporal, and 

 with the posterior auricular artery. Some offsets pass deeply to 

 supply the occipitalis muscle, the pericranium, and the bone. 



The POSTERIOR AURICULAR ARTERY (/) appears in front of the Posterior 



mastoid process, and divides into two branches. One (mastoid] is artery. 1 * 1 

 directed backwards to supply the occipitalis, and anastomoses with 

 the occipital artery. The other (auricular] supplies the retrahent 

 muscle, the back of the pinna, and the superficial structures above 

 the ear : offsets from it also pierce the pinna to be distributed on 

 the opposite surface. 



The VEINS of the exterior of the head generally correspond to the Veins of the 

 arteries in their course, and communicate freely together, as well as scall>> 

 with the sinuses in the interior of the skull by means of small 

 branches named emissary, and with the veins of the diploe of the 

 cranial bones. The frontal vein is of large size, and descends to the 

 inner end of the eyebrow, beneath which it is joined by the smaller 

 mpraorbital >- m : the resulting vessel is known as the angular vein, 

 and it forms the commencement of the facial trunk. The temporal 

 vein descends to the temporo-maxillary trunk ; the posterior auricular 

 vein to the external jugular ; and the occipital veins join the deep 

 veins at the back of the neck. 



CUTANEOUS XERVES (fig. 186). The nerves of the scalp are e 

 furnished from cutaneous offsets of both cranial and spinal nerves. 



