OF THE NERVUS OCTAVUS. 73 



Plate I fig. 5 in 1.1.) is named the antero-lateral spinal tract, GOWER'S 

 tract or the fasciculus spino-cerebellaris ascendens ventralis, but it 

 must not be confounded with the more dorsally situated fibres 

 (MONAKOW'S aberrirendes Seitenstrangbftnde! with the so-called fas- 

 ciculus rubrospinalis) between formatio gelatinosa N. V and nucleus 

 N. VII or nucleus columnae lateralis and containing descending 

 fibres. This bundle afterwards shall be recalled to mind. 



The farther path of the fibres of the antero-lateral tract is also 

 very well known. 



Near the place, where the V th root leaves the medulla those 

 fibres bend in a dorsal direction (Plate XII. fig. 17 C, f. sp. c. v.) 

 into the lateral fillet , close to the fibres of the bracchia pontis here 

 embracing the medulla. 



There they are somewhat dispersed by the appearance of the 

 nucleus ventralis lemnisci (Plate XIII. D and E fig. 18) but reunite 

 in the most lateral layer of the lemniscus lateralis, covering the 

 pedunculus superior cerebelli. 



Now they lie free at the surface on the dorsal back of the 

 peduncle, only separated from the half-moon-shaped pendunculus 

 cerebelli superior by the deeper layers of the fillet and by the 

 nucleus dorsalis lemnisci , and their course till now having been 

 always a course in proximal direction changes abruptly. 



They now turn distally and medially, cross the dorsal border 

 of the pedunculus cerebelli superior (Plate XV. fig. 14 D) and 

 end in the nuclei tecti cerebelli of the same side , or after having 

 transgressed the cerebellar medulla in those of the opposite side. 



So the course of the antero-lateral spinal tract is described by 

 many authors for instance after the hemisection of the cervical 

 medulla. 



But not all the fibres of this triangular field follow the here 

 described way. They all bend dorsally at the entrance of the tra- 

 geminus-root , but in the so-called lateral lemniscus a portion of 

 the fibres have another situation. They also surround the ventral 

 nucleus of the lemniscus, but in the medial medullar layers around 

 it. They also reach the lateral lemniscus where it covers the cere- 

 bellar superior pedunculus but as the former tract turns distally, 

 the latter tract still pursues its course (Plate XIII fig. 1 8 D) dor- 

 sally and slight proximally. They partly enter in the corpus quadri- 

 geininum posticum. These fibres participate to the secundary audi- 

 tory-system as FLECHSIG and those who studied the auditory system 

 with the my elinisation method have taught. 



Now indeed , rootsection of the nervus octavus within a fortnight 



