92 CHARLES BROOKOVER 



INTRA-CRANIAL SYMPATHETIC SYSTEM POSTERIOR TO THE 

 NERVUS TERMINALIS IN AMIA 



In addition to the fibers already described as occurring in the 

 cranial cavity on the blood vessels, there were found in numerous 

 Cajal and Golgi preparations a number of fibers among the blood 

 vessels and glandular tubes of the paraphysis. These fibers 

 could often be graced into a more or less distinct bundle near the 

 posterior lateral portion of the paraphysis. This is just outside 

 the brain membranes near the anterior edge of the optic tracts. 

 As Huber ('99) had found nerves entering the cranial cavity of 

 mammals along with the internal carotid artery near the optic 

 chiasm, search was made for a long time to discover the entrance 

 of fibers at this point in Amia, but to no purpose. Nerve fibers 

 were found entering the cranial cavity dorsally opposite the an- 

 terior end of the epiphysis (fig. 25) through a foramen by which a 

 vein apparently leaves the cranial cavity. This foramen is 

 near the alisphenoid ossification (Allis, '97) and is probably the 

 one marked "foramen for the anterior cerebral vein" (plate 

 xxi). In Weigert preparations of the head of a young Amia 100 

 mm. long there are seen to be five or six medullated nerve fibers 

 entering at this point. There are probably some non-medullated 

 ones as well, From dissections of adults there were found to be 

 three rami of this bundle diverging from a point just inside the 

 cranial cavity (fig. 25). The first ramus runs mesially at right 

 angles to the long axis of the body to a point near the anterior 

 end of the stalk of the epiphysis. A second branch runs forward 

 to be lost in gross dissections in the fat surrounding the brain. 

 The third and largest ramus turns posteriorly to a point just in 

 front of the habenular body and is distributed forward among the 

 tubules of the paraphysis, as already mentioned. Some fibers are 

 sent ventrally along the arteries to the neighborhood of the hypo- 

 physis, where nerve fibers have been found on the blood vessels. 

 Gross dissections show some variations in size and distribution 

 of these rami in different specimens. 



In one adult Amia there were found more than thirty large 

 nerve cells along the intra-cranial part of these rami. About 



