6 Journal of Comparative Neurology. 



the ear-capsule. The lateral line nerve is composed of the 

 characteristic fibers with dense sheaths. It also receives a small 

 contingent of fine fibers from the IXth and in turn gives to it a 

 small bundle of its coarse fibers.^ The IXth enters the brain 

 first (Fig. 17) and sends a bundle to the fasciculus communis 

 and one to the lateral nidus of cells, a continuation of the vagal 

 motor nidus. The lateral line nerve soon enters the dorsal 

 tract, the acusticum, just ventrad of the cerebellar crest and the 

 fibers can be traced cephalad for some distance ; whether any 

 of them enter the cerebellum or not as Goronowitsch found in 

 Acipenscr has not been satisfactorily determined ; it seems im- 

 probable. 



Ascending fibers of the Vlllth nerve may be recognized 

 at the level of the IXth, dorsad of the spinal Vth. This nerve 

 leaves the oblongata just dorsad of the spinal Vth tract. Other 

 fibers of the Vlllth seem to terminate immediately on entering 

 the brain near the characteristic large laterally situated cells, so 

 regularly found, and a few turn cephalad ; however, the rela- 

 tions in this complicated region have not been made out at all 

 satifactorily as yet. So far, Amia agrees quite closely with Aci- 

 penser, but in the origin of the remaining roots near the Vlllth 

 there is a considerable difference. In the first place there does 

 not exist in Anna the dorsal prominence present in Acipenser 

 which was termed by Goronowitsch " lobus trigemini, " and the 

 nerve root issuing therefrom {Trig. II dors, of Goronowitsch) 

 is absent as such. Very close to the Vlllth, so close as to be 

 indistinguishable from it macroscopically, there arise in dorso- 

 cephalic succession, Vllb and Vllaa;^ the former of coarse 



•Allis described the innervation of a dorsal line of free neuromasts and a 

 canal organ by fibers of the IXth nerve. Undoubtedly the fibers received from 

 the lateral line nerve have this distribution. It is precisely what we should 

 expect. 



'The names by which the roots were designated by Strong in Amphibia 

 are here used to indicate the homologous roots in fishes. The reference of Vllb 

 and Vllaa to the Vllth nerve are matters of convenience merely; Vllaa, seems, 

 however, the undoubted homologue of the "pars intermedia Weisbergii." 



The designation of the other cranial nerves by numerals is adhered to as 

 better facilitating reference. It is insignificant otherwise. 



