MEDULLA OBLONGATA 169 



Varolii is reached, when they spread out horizontally like 

 a fan (fig. 87, F.) dorsally to the deep transverse fibres. 

 Above the pons they divide into two sets (fig. 90, F.} a 

 lateral fillet, which ends in the anterior corpora quadrigemina, 

 and a mesial fillet, which passes on to the optic thalamus, and 

 there ends by forming synapses. 



2. The spino-thalamic tract passes up through the medulla, 

 and with the mesial fillet ends in the thalamus. 



3. The direct cerebellar tract passes up into the restiform 





FIG. 84 Cross Section through Medulla Oblongata above the decussation of the 

 Pyramids. P.M. and P.L., postero-median and postero-lateral tracts of 

 the cord ; N.G. and N.C., nucleus gracilis and cuneatus, giving off the 

 fillet fibres crossing at F. ; V., ascending root of fifth nerve ; G., nucleus 

 of glossopharyngeal nerve; A.H., anterior hoin of spinal cord; P., 

 the anterior pyramids ; D.C., direct cerebellar tract ; A. and D. 

 Ant.L., ascending and descending aritero-lateral tracts. (After BRUCE.) 



body, and so on to the superior vermis of the cerebellum 

 (p. 182). Its fibres form synapses round cells chiefly on the 

 opposite side. 



4. The ventro-spinal cerebellar tract passes up beside the 

 last, but it leaves it in the restiform body and courses forward, 

 to arch back into the cerebellum round the superior cerebellar 

 peduncle and to form synapses with the cells of the superior 

 vermis (fig. 87, p. 173). 



B. Outgoing. 1. The fibres from the cerebral cortex, which 



