RAMUS OPERCULARIS SUPERFICIALIS VII. 139 



In this position it begins to give off small branchlets of 

 a fev^ fibres each. One of these {pp. s. VII. j) of fine 

 fibres leaves at 580 and turns dorsad, curving around the 

 caudal projection of the hyomandibular bone where it 

 articulates with the opercular, and continues caudad along 

 the dorsal and inner surfaces of the latter bone. Here it 

 joins (600) the fourth branch of the r. opercularis vagi, as 

 described under that nerve, and the combined nerve 

 supplies the adjacent mucous lining of the operculum. 



Another branch of the r. opercularis superficialis VII 

 is somewhat larger than the last and is composed of coarse 

 fibres (<?/. s. VII. /f). It originates at the same point as 

 the last mentioned and passes caudad and dorsad by a 

 circuitous path around the base of a scale to a naked sen- 

 sory papilla {0.5) situated a short distance caudad of the 

 seventh opercular canal organ and in a line continuing the 

 direction of the sixth opercular pore. 



The fifth branch (coarse and fine fibres, op. s. VII. 5) 

 leaves also at the same point. It immediately divides 

 into several branches and supplies the skin of the opercu- 

 lum laterad and ventrad and caudad of the point of 

 origin. 



The ramus opercularis continues ventrad and caudad 

 between the opercular bone and the skin and the sixth 

 branch, containing coarse and fine fibres, separates dor- 

 sally at 612. This branch can be traced nearly to the 

 caudal edge of the operculum, running dorsally of the 

 main nerve and nearly parallel with it. The finer fibres 

 are given off to the skin early in its course. The termini 

 of the coarser ones, as in the last case, could not be deter- 

 mined by reason of defects in the sections. 



The main nerve proceeds to the extreme ventro-caudal 

 edge of the operculum, giving off several small branchlets. 



