Herrick, Cranial Nen>es of the Cod Fish. 277 



once with the combined r. opercularis superficialis VII and r, 

 hyoideus and distribute to the skin of the lower part of the 

 operculum. The remainder continue in the hyomandibular 

 trunk to the cephalic and ventral edge of the operculum, where 

 they also distribute to the skin. None of them accompany the 

 truncus into the mandible. 



The motor VII branches which constitute the r. opercu- 

 laris profundus have already been described. The second nerve 

 to leave this trunk is the large mixed nerve referred to in the 

 preceding paragraph, which from its course is clearly a fusion 

 of the r. opercularis superficialis VII and the r. hyoideus VII, 

 as I applied these terms to Menidia. It contains motor, gen- 

 eral cutaneous and lateralis fibers, and leaves the trunk imme- 

 diately upon its exit from its foramen. As the trunk turns 

 cephalad this nerve separates from it (Fig. [, op. s. -\- hy.), 

 passing outward along the cephalic face of the hyomandibular 

 bone to run caudad and ventrad along the outer surface of this 

 bone between it and the m. adductor mandibulse, and farther 

 back between this muscle and the pseudobranch. 



Just behind the hyomandibular bone, as this ramus runs 

 down along the inner face of the m. adductor mandibulae, it 

 gives off a minute twig of coarse (lateralis) fibers which retains 

 its position in the dorso-mesal edge of the muscle to its caudad 

 end. This little twig (Fig. i, r. 0, p. I.) follows the posterior 

 and ventral borders of the operculum, turning cephalad again 

 along the ventral border below the opercular canal and over- 

 lying the course of the r. hyoideus. Pit-organs are frequent 

 in the skin along its entire course and fibrils from it were in 

 several cases traced to these organs. It probably contains no 

 general cutaneous fibers, as the corresponding area of skin has 

 an independent innervation with finer fibers. This twig was 

 apparently overlooked by Cole. A larger coarse-fibered twig 

 is given off at the same time as the last. It supplies the last, 

 or 1 2th., operculo-mandibular canal organ. 



The mixed opercular and hyoideus nerve then runs down 

 along the inner side of the pre-opercular and inter-opercular 

 bones close under the mucous lining of the operculum. It 



