192 



LECTURES ON THE CENTRAL NERVOUS SYSTEM. 



roots. In addition to this the vagus and glossopharyngeal 

 apparently receive a descending root. It arises in the cere- 

 bellum, where we met it under the name of direct sensory 

 cerebellar tract. These particular fibres, passing from it to the 

 vagus, are hard to demonstrate in the human being. Apparently 



4- <U ^i Vf-^f^GS- 1 i 



"jfiS^^i'PSS^iSK " 



^^ ; ?*pcPW^ 



? JFi^^^A. yft.A'yZSUKS?'"^" xf* 



FIG. 116. 

 Frontal section through the nucleus of the hypoglossal nerve. (After Koch.J 



the sensory fibres arise from the ganglion juglare and extend 

 from it toward the cerebrum (His) just like the sensory spinal 

 nerves. The before-mentioned sensory nucleus, therefore, is 

 their second terminal point. Many curving fibres enter its 

 ventral side. By embryological methods we have succeeded in 



