THE NERVOUS SYSTEM 



1357 



the lower part of the lateral area of the bulb nearly as high as the 

 lower part of the olive, after which it passes backwards and 

 upwards into the restiform body, of which it forms a part. 



Ventral Spino-cerebellar Tract. — ^This tract, like the dorsal or 

 direct spino-cerebellar tract, extends upwards from the lateral 

 column of the spinal cord. It is situated chiefly on the dorsal 

 aspect of the olive, but some of its fibres appear close to the outer 



Fig. 569. — The Formatio Reticularis of the Medulla Oblongata, shown 

 BY a Horizontal Section passing through the Middle of the 

 Olivary Body (Demi-Schematic) (L. Testut's ' Anatomie Humaine '). 



1. Anterior Median Fissure 



2. Fourth Ventricle 



3. Formatio Reticularis 

 3 . Reticularis Alba 



3". Reticularis Grisea 



4. Raph6 



5. Anterior Pyramid 



6. Fillet 



7. Inferior Olive, with the two 



Accessory Nuclei 



7'. Peduncle of Olivary Body 13. 



8. Hypoglossal Nerve 14. 

 8'. Hypoglossal Nucleus 14'. 



9. Pneumogastric Nerve 



9'. Terminal Nucleus of Pneu- 15. 



mogastric Nerve 16. 



10. External Dorsal Auditory 



Nucleus 16'. 



11. Nucleus Ambigutis 17. 



12. Nucleus Gracilis 18. 



Nucleus Cuneatus 

 Caput of Posterior Comu 

 Lower Sensory Root of Fifth 



Nerve 

 Fasciculus Solitarius 

 External Anterior Arcuate 



Fibres 

 Arcuate Nucleus 

 Lateral Nucleus 

 Nucleus of Fasciculus Teres 



side of that body. Whilst the dorsal spino-cerebellar tract passes 

 into the restiform body and so reaches the cerebellar hemisphere 

 directly, the ventral spino-cerebellar tract is continued upwards 

 into the pons Varolii before reaching the cerebellar hemisphere. 



Restiform Body. — ^The restiform body is situated on the dorsal 

 aspect of the bulb in its upper or open part, the funiculus gracilis and 

 funiculus cuneatus occupying the dorsal aspect in its lower or closed 

 part. It succeeds to the clava and cuneate tubercle in which 



