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fibres take two separate paths. First a definite compact bundle passes 

 inward and dorsalward just lateral to the tractus spinalis n. trige- 

 mini and turns spinalward to make the tractus solitarius. Second, 

 scattered fibres pass through the tractus spinalis n. trigemini and 

 enter the ala cinerea. With these scattered fibres run the motor fibres 

 of the same nerves, as represented in the model by red wires. 



A part of the nucleus n. vestibuli medialis and the corresponding 

 fibres have been cut away to show the deeper structures, but by 

 comparing with modell II the entire nerve is made plain. Similar to 

 the N. trigeminus, the root bundle passes inward and dorsalward, and 

 then the fibres divide into ascending and descending branches. The 

 nucleus is also a continuous mass of cells lying just internal to the 

 tracts. The cells opposite the radix descendens n. vestibuli make the 

 nucleus n. vestibuli medialis while those opposite the ascending branches 

 make the nucleus n. vestibuli superior or Bechterew's nucleus. Where 

 the fibres of the vestibular root bundle divide is a third nucleus, the 

 nucleus n. vestibuli lateralis or Deiters' nucleus whose fibres pass 

 to the spinal cord. This path is to be seen in model IV. The nucleus 

 has been colored yellow (red in the atlas), because its cells do not 

 correspond strictly in type either to these of a sensory or a motor 

 nerve. The vestibular fibres which enter the cerebellum are shown by 

 wires on models II and III. The commissure between the two nuclei 

 n. vestibuli superiores is shown in model III in connection with the 

 brachium conjunctivum. 



This third model brings out the similarity between the sensory 

 paths. Each sensory nerve on entering divides into a long descending 

 tract and a short ascending one. There are however no ascending 

 fibres shown for the glossopharyngeus and vagus nerves. The sensory 

 nuclei, which are derived from the dorsal horn accompany these tracts 

 throughout their length and lie just internal to them. From all of 

 these nuclei pass internal arcuate fibres into the lemniscus medialis. 

 The vestibular nerve is peculiar in its relations to the cerebellum. 

 The cochlear nerve is not to be horaologized with the other sensory 

 nerves, either in the position of its nucleus or in the course of its 

 fibres. Its path is wholly ascending and is best seen in model IV, 

 where the corpus trapezoid eum is more uncovered. 



Besides the cerebral nerves, this model shows certain relations in 

 the midbrain, and the difi'erent areas in the formatio reticularis better 

 than the others. In the midbrain the form of the stratum profundum 

 album is prominent. Farther ventral lies the red nucleus embedded 

 in its capsule. Passing from the nucleus are the fibres of the brachium 



