72 



B. (3) The Anterior Infundibular Nerve is given 

 off from the ventral surface of the brain, at about its 

 median point (fig. TO, .4/;/. Fun. N.). It is exterior to 

 the nerve of the anterior vena cava and ventral to the 

 auditory nerve. This nerve pierces the ventral wall of 

 the cranial cartilage (fig. 69) anterior to the statocysts. 

 Between the two anterior infundibular nerves is an oval 

 aperture, through which the iwo forks of the anterior 

 aorta leave the central cavity of the brain, and 

 reach its ventral surface (see arterial system in 

 Section IV). Just before the nerve leaves the 

 cranial cavity it gives off a tine branch which 

 leaves this cavity by an independent hole, and runs 

 to the protractors of the funnel on that side. After 

 leaving the cranial cavity the anterior infundibular nerve 

 gives off a second branch which supplies the posterior 

 dorsal wall of the funnel. Some of its branches run to 

 the wall of the lateral funnel chamber. Soon after, the 

 nerve gives off a third branch to the funnel. This ends 

 in several branches which run to the median wall of the 

 funnel. The anterior infundibular nerve runs on 

 anteriorly, and soon bifurcates, both halves entering the 

 funnel wall, and both supplying eventually the dorsal 

 wall of the funnel. The lower of these two branches 

 soon swells into an oval ganglion, which is about as large 

 as the smaller of the two ganglia on the course of the 

 visceral nerve. From the anterior end of this ganglion 

 several branches run, with the strands from the upper 

 branch, to the dorsal wall of the funnel. The ultimate 

 fine branches in which all these infundibular nerves end 

 form a complete anastomosing network which quite 

 surrounds the funnel walls. 



B. (4) The Posterior Infundibular Nerve runs out 

 from (he brain just exterior to the corresponding visceral 



