642 MR. c. u. u'donoguue on tue 



of the brain, outwards, and around the posterior face of the optic 

 lobes to the ventral side of the bi'ain. Here it goes forward and 

 leaves the skull by the foramen for the trigeminal nerve. Out- 

 side the skull it bends sharply backwards and joins the lateral 

 cephalic vein as the latter reaches the intei-nal carotid artery. 

 The last part of this vessel outside the skull is a secondary con- 

 nection (V. cerebralis media secundaria, Grosser and Brezina) 

 developed between the raedian cerebral vein, which originally 

 opened into the internal jugular, and the lateral cephalic vein. 

 During its course it receives : — 



A. The Dorsal Cephcdic Vein (V. capitis dorsalis, Bruner), which 



arises from its dorsal side within the skull and passes 

 outward through a special foramen. It runs backwards 

 between the pro-otic and squamosal bones, receiving one 

 or two cutaneous veins, and their bends laterally and enters 

 the lateral cephalic vein. 



B. The Secondary Anterior Cerebral Vein, which runs on the 



floor of the cranium and joins it to the orbital sinus (vide 

 supra). 



C. The PaJato-cerebral Vein, which connects it with the oblique 



palatine vein {vide suj^ra). According to Bruner there 

 is also an external secondary anastomosis with the anterior 

 cerebral vein, as well as the internal one described above. 

 I have been unable to find this vein by dissection. 



III. A large vein from the parotid gland and the muscles of 

 the head, which closely accompanies the maxillary artery and 

 enters the lateral cephalic vein close to the place where the 

 maxillary artery leaves the internal carotid. 



IV. A Dorsal Cephalic Vein [vide supra), which joins it to the 

 median cerebral vein. 



Y. The Posterior Cerehral Vein (V, cerebi^alis posterior, Bruner), 

 which runs from the end of the longitudinal cei'ebral vein a little 

 behind the posterior end of the optic lobes obliquely outwards 

 over tlie medulla oblongata and leaves the skull by the foramen 

 magnum. Just before leaving the cranium it gives ofi" a Spinal 

 vein which runs caudally on the ventral side of the spinal cord, 

 where it unites with the similar vessel from the other side. 



VI. One well-marked and several smaller veins from the 

 muscles of the posterior end of the skvill. 



VII. A Cervical vein which returns blood from the muscles of 

 the neck. 



The Longitudinal Cerebral Vein (V. longitudinis cerebri, Brunei") 

 is a vessel running backwards along the mid-doisal aspect of the 

 brain from between the olfactory lobes. At the posterior end of 

 the optic lobes it gives off the median cerebral veins, and a short 

 distance fui'ther back divides to form the posterior cerebral 

 veins. 



