Herrick, Cranial Nerves of the Cod Fish. 297 



IX nerve in Gadus ('49, p. Jj). If glossopharyngeal fibers 

 reach the pseudobranch at all, they must play a very subordi- 

 nate role in the innervation of that structure, as compared with 

 the facialis fibers, which I have found spread out over its whole 

 anterior surface. The innervation here, as in Menidia, speaks 

 loudly in favor of regarding the pseudobranch as belonging 

 distinctively to the facial segment. 



75. The Cutaneous Root of the Vagus. 



Only a io^ij points in the morphology of the vagus will be 

 touched upon. The relations of the general cutaneous compo- 

 nent of the vagus are the chief points of interest in this con- 

 nection. The communis roots of the vagus and glossopharyn- 

 geus are long, as their ganglia lie wholly extra-cranially, as 

 usual among the teleosts, and the cranial wall is here much far- 

 ther from the brain than in Menidia. The vagal roots arise 

 much as in Menidia, the lateralis root running out dorsally of 

 all of the others and the motor roots ventrally. The general 

 cutaneous component is larger than in Menidia and arises from 

 the spinal V tract in the caudal region of the root complex and 

 going out with its first root. Its ganglion, the jugular ganglion, 

 is intra-cranial and lies as close as possible to the brain, for the 

 most part ventrally of the other root fibers. It is therefore far 

 separated from the other ganglia of the vagus. 



The fibers arising from the jugular ganglion run out and 

 up along the cephalic side of the root complex and pass out of 

 the cranium appressed to the ventral side of the lateralis root. 

 They pass into the r. supra-temporalis vagi, and accompany 

 these lateralis fibers to the skin about the lateral line canal near 

 the supra-temporal commissure. Thus the r. cutaneous dorsalis 

 and the r. supra-temporalis are in Gadus fused into a common 

 trunk. This is clearly the course of most of the fibers from 

 the jugular ganglion. There may be other fibers, though I was 

 unable to trace any others through the complex. 



The vagal root of the r. lateralis accessorius arises from 

 root fibers which pass very near to the jugular ganglion, but I 

 could not demonstrate any fibers from this ganglion to that 



