624 THE VEINS 



pass, in part into the inferior longitudinal sinus, and in part into the cavernous 

 sinus. Those on the temporo-sphenoidal lobe enter in part into the superior 

 petrosal sinus, and in part into the lateral sinus, passing into the latter from before 

 backwards. A large vein from the occipital lobe winds over the crus cerebri and 

 joins the great vein of Galen just before the latter enters the straight sinus. One 

 of the inferior cortical veins is sometimes called the middle cerebral vein; another 

 the great anastomosing vein of Trolard; another the posterior anastomosing vein of 

 Labbe. The first ramifies over the under surface of the frontal and temporo- 

 sphenoidal lobes, and at the anterior and lower part of the fissure of Sylvius opens 

 into the cavernous sinus. The second establishes a communication between the 

 superior longitudinal and cavernous sinuses by anastomosing with the middle 

 cerebral and one of the superior cortical veins. The third passes from the middle 

 cerebral vein over the temporo-sphenoidal lobe to the lateral sinus. 



The central, ganglionic, or deep cerebral veins are collected into two large 

 venous trunks, the vense Galeni, which leave the brain at the great transverse 

 fissure, that is, between the splenium of the corpus callosum and the optic lobes. 

 At this spot they unite to form a single vein, the vena magna Galeni, which 

 opens into the anterior end of the straight sinus. The vense Galeni are formed by 

 the union of the choroid vein with the vena corporis striati near the foramen of 

 Monro. From this spot they run backwards parallel to each other between the 

 layers of the velum interpositum, and terminate in the way above mentioned. 



Tributaries of the veins of Galen. — The choroid vein, the vein of the corpus 

 striatum, the basilar vein, the veins of the optic thalamus, the vein of the choroid 

 plexus of the third ventricle, and veins from the corpus callosum, the pineal body, 

 the optic lobes, and posterior horn of the lateral ventricle. The united trunk, or 

 great vein of Galen, receives veins from the upper surface of the cerebellum, and 

 one of the posterior inferior cerebral veins. 



The choroid vein runs with the choroid plexus. It begins in the inferior cornu 

 of the lateral ventricle, and ascends on the outer side of the choroid plexus along 

 the margin of the velum interpositum to the foramen of Monro, where it unites 

 with the vein of the corpus striatum to form the vein of Galen. It receives tribu- 

 taries from the hippocampus major, corpus callosum, and fornix. 



The vena corporis striati, formed by veins from the corpus striatum and optic 

 thalamus, runs forwards in the groove between those structures, passing in its course 

 beneath the taenia semicircularis, and joins the vein of Galen at the foramen of 

 Monro. Tributaries. — It receives, in addition to the veins from the corpus stria- 

 tum and optic thalamus, small veins from the fornix, septum lucidum, and 

 anterior cornu of the lateral ventricle. 



The basilar vein, formed by the confluence of the deep Sylvian vein, the 

 inferior striate veins, and some small anterior cerebral veins, runs backwards over 

 the crus cerebri, and enters the vein of Galen near the union of that vessel Avith 

 the vein of the opposite side. Tributaries. — The deep Sylvian vein from the insula 

 and surrounding convolutions; the inferior striate veins from the corpus striatum, 

 which they leave through the anterior perforated space; anterior cerebral veins 

 from the front of the corpus callosum; interpeduncular veins from the structures 

 in the interpeduncular space; ventricular veins from the middle cornu of the lateral 

 ventricle; and mesencephalic veins from the mid-l»rain. 



The Cerebellar Veins 



The cerebellar veins are divided into the superior and inferior. 



The superior ramify on the upper surface of the cerebellum; some of them 

 run inwards over the superior vermiform process to join the straight sinus and 

 great vein of Galen; others run outwards to the lateral and superior petrosal 

 sinuses. 



The inferior, larger than the superior, run, some forwards and outwards to the 

 inferior petrosal and lateral sinuses, and others directly backwards to the occipital 

 sinuses. 



