48 Journal of Comparative Neurology. 



pit organs of the ventral row as described by Alcock ('98). 

 The vagus trunk also receives a large component of lateral line 

 fibers from the VII-X anastomosis, as will be described below. 



The post-auditory lateral line root sends the greater part 

 of its fibers into the dorsal limb of its V-shaped ganglion. The 

 lateral limb gives rise to one large ramus besides the fibers 

 which enter the IX trunk. This ramus divides into two main 

 branches and several twigs. One of the main branches runs 

 outward, upward, and forward around the auditory capsule and 

 innervates the lateral Hne organs of the post orbital row which 

 passes ectal to the ear. The small twigs run laterally above the 

 gill sacs and probably innervate some of the more dorsally sit- 

 uated organs on the side of the head. The dorsal limb of the 

 lateral line ganglion rectives the greater part of the VII-X anas- 

 tomosis. The fibers of this anastomosis together with those 

 from the ganglion form a longitudinal trunk which runs both 

 forward and backward irom this point. It is the Nervus 

 lateralis (see discussion below). The caudal portion of 

 this nerve, which lies lateral to the spinal canal through- 

 out the length of the body, is well known. I have not 

 seen any description of the cephalic portion. It extends for- 

 ward from the upper limb of the ganglion above the auditory 

 capsule, and presumably innervates the pit organs near the mid- 

 dorsal line as far forward as the pineal gland. The lateral line 

 nerve is thus composed of lateral line fibers with the possible 

 exception of an almost insignificant number of communis fibers 

 which it may receive from the VII through the anastomosis. 

 The communis fibers which appear to enter the anastomosis 

 from VII may be distributed to end-buds before that anasto- 

 mosis joins the lateral line nerve. 



That portion of the VII— X anastomosis which does not 

 enter the N. lateralis passes down outside of the dorsal limb of 

 the lateral line ganglion and joins the outer surface of the vagus 

 trunk. It is presumably these fibers which innervate the pit 

 organs of the ventral row, as described by Alcock. It is a 

 very striking fact that these ventral organs in the gill region 

 should be supplied by lateral line VII fibers, i. e., by pre- and 



