• ANGEIOLOGY. 97 



form the angular vein, which runs downwards and outwards by the inner 

 margin of the orbit, resting against the side of the root of the nose. It 

 receives the nnsa/ veix.'^ from the side and ridge of the nose, and some small 

 palpebral veins open into it from the opposite direction. When arrived on 

 a level with the lower margin of the orbit, the angular vein terminates by 

 becoming continuous with the facial vein. 



The facial vein, thus started, increases by recurving branches from the 

 lower eyelid, and from the ala of the nose and from its outer side, the infe- 

 rior palpebral vein. Lower down it is joined by branches from the lip and 

 cheeks, and uniting with a branch from the temporal vein, empties into the 

 trunk of the internal jugular. Previously, however, it receives the ranine 

 vein, from the tongue, the submental vein, and the palatine vein. 



The Temporal Vein is a vessel of considerable size, extending from 

 the zygoma to the angle of the jaw, while its branches spread out on the 

 sides of the head. The principal of these branches are, the posterior tempo- 

 ral, the middle temporal, and the anterior temporal. Sinking below the angle 

 of the jaw, it divides into two branches, of which one joins the facial vein, 

 and the other becomes continuous with the external jugular vein. Other 

 branches opening into the temporal vein are, the parotid, the articular, the 

 auricular, the transversalis faciei, and the auricularis posterior. A vein of 

 considerable size, joining the temporal in the parotid gland, is : 



The internal maxillary. This receives branches from the temporal fossa, 

 from the pterj^goid muscles, from the surface of the upper jaw, and from 

 the lower through the dental foramen. 



The External Jugular Vein commences on a. level with the angle of 

 the jaw by the union of two branches, one the communicating branch from 

 the termination of the temporal vein, the other from the mastoid region. 

 Descending vertically, it unites with the subclavian. The principal veins 

 which open into it are, the anterior jugular from the fore part of the chin, 

 and from the scapular region, the supra-scapidar and the, posterior scapular. 



Cerebral Veins. The venous system within the skull consists of veins 

 properly so called, and sinuses or reservoirs. The former we shall not con- 

 sider in this place. The sinuses of the cranial cavity may be divided into 

 two sets, those placed in the prominent folds of the dura mater and those 

 disposed at the base of the skull. The former all converge more or less to 

 a common point, which corresponds to the internal occipital protuberance, 

 and is called the torcular herophili. The sinuses are as follows: 1. The 

 superior longitudinal sinus, extending from before, backwards in the upper 

 part of the falx cerebri, and commencing at the crista galli. 2. The inferior 

 longitudinal sinus. This very small sinus is placed in the inferior concave 

 border of the falx, and opens into the straight sinus. 3. The straight sinus, 

 a continuation in a measure of the last, runs backwards in the direction of 

 the base of the falx cerebri. 4. The lateral sinuses. Their direction con- 

 forms to that of the groove on the interior of the occipital bone, and passing 

 from the protuberance to the foramen lacerum posterius. 5. The posterior 

 occipital sinus, which conducts from the posterior margin of the foramen 

 magnum to the torcular. 



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