412 Journal of Comparative Neurology, 



cerebro-spinal ganglion, the central processes of its cells enter 

 the portio intermedia of Wrisberg and the fasciculus solitarius to 

 terminate with the gustatory fibers of the glossopharyngeus in 

 the associated grey matter. The peripheral processes of these 

 geniculate ganglion cells in part enter the great superficial 

 petrosal nerve and in much greater number the facialis trunk. 

 Most of the latter fibers leave the trunk within the Fallopian 

 canal and pass back by a separate canal in the temporal bone 

 to cross through the tympanic cavity and join the lingual branch 

 of the trigeminus for taste buds on the tip of the tongue. This 

 is the chorda tympani. A much smaller number of sensory 

 fibers has recently been shown to remain in the facial trunk after 

 the separation of the chorda. 



This, I think, may fairly be said to represent the consen- 

 sus of recent opinion. Its receives strong confirmation from 

 the study of the comparative anatomy of the facial nerve ; and 

 not only so, but its morphological interpretation, as well. 



It is now pretty generally recognized that the facial nerve 

 of fishes is a very typical branchial nerve, in selachians branch- 

 ing around the spiracular cleft as tiie IX and X nerves fork 

 around their respective gill clefts and sending forward a palatine 

 branch corresponding to the r. pharyngeus of the other branch- 

 ial nerves. 



The composition of the branchial nerves in the fishes can 

 be stated with precision. The post-trematic branch runs down 

 behind the cleft to supply the half gill on its posterior wall and 

 the muscles of that arch. It is, therefore, of mixed motor and 

 sensory function. The pre-trematic branch supplies the half 

 gill in front of the cleft and the pharyngeal, or palatine, branch 

 the mucosa of the roof of the pharynx adjacent, both of the 

 two latter being wholly sensory. All of. the sensory fibers be- 

 long to the communis system, fibers associated with the fasci- 

 culus communis (f solitarius) and its terminal nuclei and sup- 

 plying visceral surfaces and taste buds. The motor fibers be- 

 long to the viscero-motor system innervating the branchial mus- 

 culature or its derivatives. The facialis conforms exactly to 

 this scheme, save that in all fishes the post-spiracular half gill 



