CoGHiLL, Cranial Nerves of Triton. 255 



either nerve is made up of one component exclusively. But it is 

 certain that if the r. buccalis receives general cutaneous fibers at 

 any point, the number of such fibers is exceedingly small. The 

 r. buccalis is always composed of uniformly large fibers, which 

 are characteristic of the acustico-lateralis system. Also, if 

 lateralis fibers occur in the r. maxillaris, they are very few and of 

 irregular occurrence. 



These tw^o nerves do not difl^er in any important feature from 

 the corresponding nerves of Amblystoma till they reach the level 

 of the cephalic border of the eye. Here, or in some cases consider- 

 ably farther cephalad, the r. maxillaris passes through the maxil- 

 lary bone and passes outward and downward into the upper lip; 

 while the r. buccalis, ordinarily lying farther mesad, sends a 

 slender filament mesad, which penetrates the cartilaginous wall 

 of the nasal capsule and, passing around the caudal border of the 

 nasal epithelium and the internal nares, joins the mesial branch 

 of the ophthalmico-palatine nerve. This communicating nerve 

 is sometimes fused with the lateral terminal branch of the palatine, 

 but in some instances it is wholly separated from this nerve and 

 from the palatine ganglion also, and joins the nerve from this 

 ganglion only after passing a considerable distance cephalad 

 mesially of the internal nares. 



On one side of one of my specimens the nerve in question arises 

 from the r. maxillaris. Yet, since in this one exception, because 

 of the intimate relation of the r. maxillaris with the r. buccalis, it 

 is possible that lateralis fibers are carried out with the r. maxil- 

 laris, the natural inference is that this communicating nerve belongs 

 to the acustico-lateralis system. This interpretation is further 

 borne out by the fact that the terminal twig of the palatine nerve, 

 with which this nerve unites, after traversing the whole length of 

 the nasal chamber ventrally of the nasal epithelium, passes 

 through the cephalic wall of the capsule and through the pre- 

 maxillary bone and terminates in the lateral line organs at the 

 very tip of the snout. 



Just outside the foramen in the premaxillary bone this terminal 

 filament of the palatine crosses a branch of the mesial terminal 

 ramus of the ophthalmicus profundus which carries general 

 cutaneous fibers from the adjacent region. Since the latter nerve 

 does not at any point come into close relation with the acustico- 

 lateraHs system of fibers, and since no lateraHs fibers from any 



