46 OLOF LARSELL 



brain, both on the ventral surface and in the sagittal jfissure. 

 In all cases in which their connection could be determined, when 

 followed toward the ventral surface of the brain such strands led 

 to the principal branches of the anterior cerebral artery, and 

 connected with the main nerve bundle of the terminalis. When 

 the overlying connective tissues were successfully removed the 

 white nerve strands stood out clearly against the reddish brown 

 of the blood-vessels. The larger bundles were followed with 

 comparative ease even with the unaided eye, and w^ere not easily 

 torn. It is unlikely that all of the finer bundles were left intact. 

 The relatively long stretches on some of the arteries shown in 

 figure 33 where no twigs are represented probably indicate areas 

 where they were inadvertently torn in dissection. Those shown 

 in other parts of the vessels could be raised upon the point of a 

 needle and stretched in such a manner as to clearly show that 

 the finer twigs into which they ramify enter the walls of the 

 blood-vessels. 



Caudally, the principal roots which by their union form the 

 nerve trunk, follow along the larger vessels as far as the latter 

 could be traced without cutting into the brain. In most of the 

 specimens examined the internal carotid artery had been severed 

 so close to the brain in removing the organ that it was not pos- 

 sible to determine with certainty that any of it was present. 

 There seems little doubt, however, that the continuation of 

 strands from the main trunk of the terminalis unites with the 

 plexus surrounding the internal carotid. 



A branch from the main bundle was also followed along the 

 posterior ramus of the anterior cerebral artery as far as the genu 

 of the corpus callosmii, and similarly on other rami of this vessel 

 nerve strands were observed. 



Evidence of direct connection with the brain was difficult to 

 obtain. Delicate branches from the nerve strands on the arteries 

 were found occasionally to enter openings in the anterior per- 

 forated space. These branches were extremely difficult to dis- 

 entangle from the mass of small blood-vessels, connective tissue, 

 and elastic fibers among which they were found. Many ap- 

 peared to be related to the larger vessels which enter the brain 



