FINAL KEVIEW. 409 



from the opposite niicleus of the bulb. And in this nucleus itself terminate 

 the processes from the cells of the Gasserian ganglion. 



The trigeminus also arises in part from nuclei lying in the central organ 

 itself. So far we know two of these: one in the lateral wall of the aqueduct 

 beneath the corpora quadrigemina; the other, the so-called motor nucleus, 

 lying in the pons. 



The ascending root contains the tactile nerves of the face, as is shown 

 by pathology. 



11. The nervus acusticus is conveniently regarded as two nerves: the 

 nervus cochlearis and the nervus vestibularis. 



The cortical origin of the nerve of hearing, the cochlear, must be sought 

 in the region of the temporal convolutions. Clinical observations allow the 

 conclusion that from there a tract leads to the inferior portion of the internal 

 capsule, and probably through the arm of the posterior corpus quadri- 

 geminum to its gray matter. Thence the lateral lemniscus extends down- 

 ward toward the superior olive in the oblongata, and in this end also the 

 fibers from the nucleus acustici ventralis, the trapezoid body. In this 

 nucleus, however, arborize the end-branches from the ganglion-cells of the 

 ganglion spirale cochleae: the auditory nerve-roots. 



About the central course of the nervus vestibuli but little is known. Its 

 fibers, coming from the cells of the macula and the crista acustica, end 

 partly in the dorsal nucleus and extend partly to the cerebellum. Besides, 

 this nerve contains fibers from lower levels of the oblongata, and additions 

 from the lemniscus as striae acusticse (compare description given previously). 



The upper olive, with which not only the cochlear, but also the ves- 

 tibular, stands in relation, is intimately connected with the nuclei of the 

 motor nerves of the eye and with the cerebellum; probably also with the 

 corpora quadrigemina. It is likely that it belongs to the equilibration- 

 apparatus of the body. 



The trigeminus, as well as the acusticus, receives fibers from the cere- 

 bellum. 



12. Nothing is known about the central tract of the vagus. If the 

 much-mentioned place in the posterior part of the capsule be destroyed, 

 vagus symptoms do not appear; instead, there come disturbances of taste 

 (glosso-pharyngeus). The course of the fillet-fibers to the opposite pneumo- 

 gastrie and glosso-pharyngeal nuclei has been mentioned. Both these nerves 

 also probably receive additional fibers from the cerebellum. 



13. The central course of the opticus has already been considered in its 

 relations. 



It may be repeated that this nerve arises from the pulvinar thalami, 

 the corpus geniculatum laterale, the tuber cinereum, and the corpora quad- 

 rigemina; that it receives fibers, arising in the retina, which end in the 



