132 C. WINKLER. THE CENTRAL COURSE 



y. to the fasc. long, posterior (descendent praedorsal tract] and 

 having crossed the raphe. 



J. to the contra-lateral fasc. long, posterior and through it to the 

 contra-lateral nucleus VI. 



6. the dorsal root fibres to the radix descendens and to the radix 

 ascendens N. VIII. 



In distal regions these fibres penetrate through the portio interim 

 C. R. to reach the field of the descending root. 



In proximal regions as the ped. cerebelli inferior retires to the 

 cerebellum, dorsal and medial trunk fall together, and the most 

 proximal dorsal rootfibres even reach the nucleus of BECHTEREW and 

 the nuclei tecti. Their course will be schematised in the description 

 of the ventral (medial trunk) root-fibres. 



A more important set of fibres however are 



7 the dorsal rootfibres to the intermedia! system. They curvate 

 around the area ovalis, perforate through the gelatinous substance 

 of the V th spinal root towards the field of the so-called aberrirendes 

 Seitenstran gbiin del . 



They participate to the SYSTEM A INTERMEDIUM NERVI OCTAVI. 



This system sends some fibres 



u. in longitudinal direction. 



otot, Very few distally (beginning descendent tract), /3/3 

 more proxiinalward towards the nuclei tecti (ventral ascending 

 spino-cerebellar tract). 



fl. in the facial nucleus. 



y. in the sy sterna ventralis N. octavi. 



More fibres in the 



<J. dorsal medullar layers of the nucleus olivaris superior. 



But the majority of its fibres become. 



s. transverse intermediary fibres (HELD) which are passing the 

 raphe, giving a few fibres in distal direction tho the praedorsal 

 tract and also a few fibres to 



ex, the medial hilus of the contra-lateral oliva and to its 



dorsal layer. 

 /3 in the contra-lateral ,,aberrirendes Seitenstrangbiindel" . 



Together the latter fibres go proximally, to become 

 . dorsal rootfibres reaching through the intermediary system the 

 contra-lateral fillet and the corp. quadrigeminum posticum. 



II. IN THE MEDIAL TRUNK only a few fibres enter. They will be 

 schematised in the description of the ventral rootfibres. 



