284 Journal of Comparative Neurology. 



fibres of the auditory root varies widely, some fibres 

 being very coarse, as large as those of the lateral line 

 roots, though most are of medium size, while some are 

 quite fine. The latter are scattered among the coarser 

 ones in rather close bundles at first. Inasmuch as it 

 was not possible to trace the different kinds of fibres 

 to distinct origins centrally, nor to follow them with 

 precision through their ganglia, the detailed account of 

 the ramuli will hardly be necessary, for the descriptions 

 of Retzius ('81) amply cover the topographical relations. 

 These relations are shown on Figs. 5, 17, 18, 19, 20, 21. 



Section 7. — The Trigemino-Facial Complex. 



The fifth and seventh nerves have been confused in the 

 descriptions of the earlier writers upon the bony fishes 

 and such confusion was inevitable so long as the method 

 of dissection alone was relied upon. Those who have 

 studied these nerves microscopically have confined their 

 observations to their root portions, and because of their 

 ignorance of the peripheral courses of these roots have 

 often been led into errors of interpretation. I have suc- 

 ceeded in following all of the facial and trigeminal roots 

 through the ganglionic complex with precision and most 

 of the fibres have been traced to their peripheral endings 

 with equal certainty. The roots of the fifth and seventh 

 nerves are as distinct in Menidia as in any vertebrate, all 

 of the fifth roots emerging at one transverse level and the 

 seventh at another. These two root complexes are, 

 however, so close together and so intimately joined im- 

 mediately after their exit from the brain that their exact 

 analysis would be impossible by dissection. All of their 

 ganglia fuse into one mass and are indistinguishable 



